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1

Dicks, Steven E. "Satellite-derived surface temperatures and their relationships to land cover, land use, soils and physiography of North-Central Florida." Gainesville, FL, 1986. http://www.archive.org/details/satellitederived00dick.

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2

Ellsäßer, Florian [Verfasser]. "Predicting evapotranspiration from drone-recorded land surface temperatures - Method testing and development / Florian Ellsäßer." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1217481508/34.

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3

Kabsch, Ewa [Verfasser], and H. P. [Akademischer Betreuer] Bähr. "Validation of land surface temperatures from MSG satellite measurements by observations at the ground station near Evora, Portugal / Ewa Kabsch. Betreuer: H.-P. Bähr." Karlsruhe : KIT-Bibliothek, 2009. http://d-nb.info/1013805585/34.

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4

Jiang, Geng-Ming Li Zhao-Liang. "Retrievals of land surface emissivity and land surface temperature from MSG1-SEVIRI data." Strasbourg : Université Louis Pasteur, 2008. http://eprints-scd-ulp.u-strasbg.fr:8080/848/01/JIANG_Geng_Ming_2007.pdf.

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5

Jiang, Geng-Ming. "Retrievals of land surface emissivity and land surface temperature from MSG1-SEVIRI data." Université Louis Pasteur (Strasbourg) (1971-2008), 2007. https://publication-theses.unistra.fr/public/theses_doctorat/2007/JIANG_Geng-Ming_2007.pdf.

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Les objectifs de cette thèse sont concentrés sur la détermination de l’émissivité (LSE) et de la température de surface (LST) des surfaces terrestres à partir des données de MSG 1 -SEVIRI. Dans un premier temps l’inter-calibrage des canaux infrarouges 4, 9 et 10 de MSG I -SEVIRI avec les canaux de Terra-MODIS est réalisé. Deux méthodes, la méthode «ray-matching» et une méthode basée sur l’équation transfert radiatif ont été appliqués. Les résultats indiquent que les anomalies de calibrage existent entre les canaux de SEVIRI et de MODIS. L’utilisation des résultats obtenus par la méthode basée sur le transfert radiatif pour recalibrer les données de SEVIRI est recommandée. Ce recalibrage permet de supprimer la surestimation des LSTs obtenues à partir des données de SEVIRI avec une méthode SplitWindow. Les émissivités sont ensuite estimées dans les canaux 4, 7, 9 et 10 sur des grandes étendues spatiales et temporelles en utilisant une méthode basée sur le concept des TISI. Une nouvelle méthode de corrections atmosphériques a été développée, principalement basée sur le modèle de DTC (Diumal Time Cycle), et deux modèles de BRDF, le modèle du Minnaert modifié et le modèle de RossThick-LiSparse-R, ont été évalués. Les températures de surface sont déterminées à partir des données MSGI-SEVIRJ et AATSR. La méthode mono canal simple et la méthode Split Window ont été utilisées. Les algorithmes généralisés de Split Window ont été développés pour les instruments SEVIRI et AATSR en utilisant le code MODTRAN et les profils atmosphériques standards et ont été appliqués avec succès aux déterminations des LST à partir des données de SEVIRI et d’AATSR. Les températures de surface obtenues à partir de SEVERI ont été validées par comparaison directe avec les produits MODIS/Terra LST et les AATSR LST estimées par la Split Window généralisée au-dessus de la péninsule ibérienne et d’une région de l’Egypte et du 1Moyen-est. Les résultats indiquent que les LST SEVIRJ sont conformes au LST extraites des produits MODIS/Terra LST et AATSR LST avec une exactitude comprise entre l-2 K.
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6

Yang, Jiansheng. "Remote sensing modeling of land surface temperature /." View online ; access limited to URI, 2003. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3112133.

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7

Dash, Prasanjit. "Land surface temperature and emissivity retrieval from satellite measurements." Karlsruhe : Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft, 2005. http://bibliothek.fzk.de/zb/berichte/FZKA7095.pdf.

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8

Mitchell, Bruce Coffyn. "Urbanization and Land Surface Temperature in Pinellas County, Florida." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3250.

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Since the early 1800's, many studies have recognized increased heat in urban areas, known as the urban heat island (UHI) effect, as one of the results of human modification to the natural landscape. UHI is related to differences in land surface temperature (LST) between rural areas and urban areas where factors of the built environment such as the thermodynamic capacities of materials, structural geometry, and heat generating activities cause increased storage and re-radiation of heat to the atmosphere. This thesis examines the correlation between factors of urbanization and differences in land surface temperature (LST) in the subtropical climate of Pinellas County, Florida using remote sensing techniques. It describes the spatial pattern of LST, analyzes its relationship to factors of urbanization relative to NDVI, percentage of impervious surface, and land use land cover in the study area. It also assesses the effectiveness of remote sensing as an efficient method of identifying LST patterns at the local and neighborhood level for mitigation strategies. Landsat TM thermal band imagery for three dates; April 1986, 2001 and 2009 was processed using Qin's mono-window algorithm (MWA) technique to derive LST levels. This data was compared to in-situ readings, then normalized and statistically analyzed for correlation with vegetation ratio (NDVI) and imperviousness percentages derived using linear spectral mixing/unmixing, and also with land use/land cover classification. The resulting LST spatial pattern is a gradient across the peninsular landscape, from cooler water and wetland areas to a generally warmer interior, interspersed with micro-urban heat islands (MUHIs), corresponding to urban structures and "cool-islands" of parkland and lakes. Correspondence between LST pattern and urban structures and land use demonstrates the suitability of medium resolution remote sensing data and techniques for identifying micro-urban heat islands (MUHIs) for possible mitigation. Mitigation could include relatively low-cost measures like replacement of inefficient asphalt roofs with more reflective and emissive "cool roofs," placement of "street trees" to enhance shade, and replacement of impervious pavements by permeable surfaces. The thesis concludes that Landsat TM imagery processed with the MWA provides an efficient, relatively low-cost method for locating MUHIs. Satellite remote sensing, combined with aerial photography can facilitate neighborhood level analysis for the implementation of low-cost mitigation techniques. Previous studies have demonstrated that these are successful ways to mitigate the UHI effect at the micro-scale level; lowering urban heat and saving energy, and also facilitating the reintegration of natural elements into the urban environment.
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9

Boonmee, Marvin. "Land surface temperature and emissivity retrieval from thermal infrared hyperspectral imagery /." Online version of thesis, 2007. http://hdl.handle.net/1850/5868.

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10

Simões, Débora de Souza. "Ambiente físico e meteorológico para análise do risco de geada." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/132123.

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A geada é um fenômeno meteorológico adverso que causa perdas severas ao setor agrícola, em especial no Sul do Brasil. A baixa distribuição espacial da rede de estações meteorológicas dificulta o monitoramento e a previsão do fenômeno. O propósito principal desta tese foi o desenvolvimento de um modelo matemático para quantificar de forma direta e simples a probabilidade do risco de ocorrência de geada tendo como base em dados de fácil obtenção como altitude, latitude, continentalidade e temperatura do ar. O modelo criado, denominado Risco Geral de Geada (RGG), foi idealizado a partir de dois riscos básicos, o risco geográfico e o risco advindo da temperatura mínima do local, ambos com o mesma contribuição para a ocorrência de geada. O risco geográfico de geada (RGeo) foi obtido a partir do somatório dos riscos atribuídos aos fatores geográficos altitude, latitude e continentalidade. Cada um destes fatores contribui de forma diferente para a formação da geada e suas contribuições foram estimadas a partir de um modelo de regressão linear múltipla para a estimativa da temperatura mínima do ar climatológica de inverno no Rio Grande do Sul. No risco de geada associado à temperatura mínima (RTmín) foi feita a atribuição de riscos em um intervalo de temperatura entre 0 e 6°C. O modelo final obtido, válido apenas para o Rio Grande do Sul, foi testado com dados coletados em estações meteorológicas de superfície da mesorregião do Sudeste Rio-grandense, localizadas em Encruzilhada do Sul, Rio Grande e Santa Vitória do Palmar. Dados de temperatura mínima do ar nos meses de junho, julho e agosto, coletados entre os anos de 1961 e 2015, comprovaram a utilidade do modelo RGG para a definição da probabilidade do risco de ocorrência de geada, mesmo diante de incertezas atribuídas a outros fatores não descritos no modelo. Na região de teste também foi avaliada a qualidade de dados orbitais de temperatura da superfície terrestre (TST), obtidos do produto MDY11A1 da passagem noturna do sensor MODIS/AQUA, na detecção de temperaturas baixas relacionadas com a ocorrência de geada. A frequência de dias com TST inferiores a 3°C mostrou coerência tanto com os dados observados em estação meteorológica, quanto com o risco determinado pelo RGG. A coerência entre os resultados obtidos do modelo RGG e os dados reais observados em superfície e obtidos por satélite torna o modelo útil na descrição da probabilidade do risco de ocorrência de geada sobre o Rio Grande do Sul.<br>Frost is an adverse meteorological phenomenon that causes severe losses to the agricultural sector, especially in Southern Brazil. Low spatial distribution of the network of meteorological stations hinders monitoring and forecast phenomenon. The main purpose of this thesis was to develop a mathematical model to measure directly and easily the probability of the risk of frost based on readily available data such as altitude, latitude, continentality and air temperature. The model, called Frost General Risk (RGG), was designed from two basic risk, geographic risk and risk arising out of the local minimum temperature, both with the same contribution to the occurrence of frost. The geographical risk of frost (RGeo) was obtained from the sum of the risks attributed to geographical factors altitude, latitude and continental influence. Each of these factors contributes differently to the formation of frost and their contributions were estimated from a multiple linear regression model to estimate the minimum air temperature winter climatological in Rio Grande do Sul. In the frost risk associated with minimum temperature (RTmín) assigning risk was taken in a temperature range between 0 and 6° C. The final model obtained, valid only for the Rio Grande do Sul, has been tested with data collected from weather stations surface of the middle region of Sudeste Rio-grandense, located in Encruzilhada do Sul, Rio Grande and Santa Vitória do Palmar. Minimum temperature, the air in the months of june, july and august, collected between 1961 and 2015, have proved the usefulness of the model RGG to define the probability of the risk of frost, even in the face of uncertainty attributed to other factors not described in the model. In the test region was also evaluated the quality of satellite data of the land surface temperature (LST), the product obtained MDY11A1 the night passage of MODIS / AQUA sensor to detect low temperatures related to the occurrence of frost. The frequency of days with LST below 3° C showed much consistency with the observed data in weather station, and with the particular risk for the RGG. Consistency between the results obtained from the RGG model and the actual data observed in surface and from satellites makes the model useful in describing the probability of the risk of frost on the Rio Grande do Sul.
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11

Shepherd, Andrew. "Land surface temperature derived from the Along Track Scanning Radiometer." Thesis, University of Leicester, 1999. http://hdl.handle.net/2381/27902.

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Terrestrial radiometric surface temperatures were recorded at multiple observation angles in conjunction with satellite overpasses of the Along Track Scanning Radiometer (ATSR) over two florally distinct regions of Zimbabwe. The experimental sites were, respectively, an open grassland savannah and a medium density natural woodland, each of which extended over some 1000 square kilometers of predominantly flat terrain. The principal surface components at each location were vegetation and soil in varying proportions. Infrared brightness temperatures were corrected for atmospheric effects using solutions to the radiative transfer equation with coefficients derived from local atmospheric radiosoundings. The empirical equations of Idso (1981) and the RADGEN radiative transfer model (Zavody et al., 1995) were used to derive atmospheric emittance and transmittance for the in-situ and ATSR data respectively. Both in situ and ATSR derived radiative temperatures exhibited a pronounced angular variation over each surface, with differences upwards of 5°C between measurements at nadir and forward (55°) zenith angles. This effect has been attributed to the temperature differentials that exist within heterogeneous canopies, which typically display variations in vegetation cover related to the observation angle. A simple two component canopy architecture was coupled with a linear mixture model to partition the ensemble surface emission. The fractional vegetation cover was estimated using multi-angle radiative temperatures and was in excellent agreement with in situ estimates. Empirical equations were derived from the in situ data which related vegetation and soil temperatures at each location. These relationships were used to constrain the surface component temperature regime so that ATSR dual-angle radiative surface temperatures were sufficient to derive the vegetation and soil temperatures and fractional cover. The difference between canopy and soil temperatures separated using the dual-angle data was greater than 30°C at certain times of the year, and the modal standard deviation for all component temperature estimates was 3.2°C.
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12

Bateni, Sayed Mohyeddin. "Estimation of turbulent surface heat fluxes using sequences of remotely sensed land surface temperature." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/66850.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2011.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 330-366).<br>Fluxes of heat and moisture at the land-surface play a significant role in the climate system. These fluxes interact with the overlying atmosphere and influence the characteristics of the planetary boundary layer (e.g. temperature and water vapor content), ultimately influencing the presence and growth of low level clouds and precipitation. Nevertheless, there is currently no network of in situ sensors that can map these fluxes globally. Recently a number of studies have focused on the estimation of surface energy flux components based on the assimilation of land surface temperature (LST) within a variational data assimilation (VDA) framework. This study provides the theoretical basis for why sequences of LST contain the necessary information to estimate surface fluxes with minimal reliance on ancillary data and empirical parameterizations. Furthermore this study addresses one of the main drawbacks of the existing VDA models. They use the simple force-restore equation for soil heat diffusion as a physical constraint. The force-restore equation provides a simplified description of the LST dynamics. Also, its performance is highly affected by the specification of a deep ground temperature. These shortcomings cause significant errors in the diurnal dynamics of heat diffusion in the soil and ultimately the retrieval of components of surface energy balance. This study advances the VDA scheme by using the full heat diffusion equation as a constraint in lieu of the forcerestore approximation. The new VDA scheme is tested over several experimental field sites. The results show that inclusion of the heat diffusion equation decreases the phase error associated with the ground heat flux diurnal cycle, and improves surface heat flux estimation. The VDA scheme is further advanced by incorporating model uncertainty in order to account for measurement and model errors. Tests indicate that the VDA scheme with model uncertainty captures measurement errors as well as structural model errors. In order to provide coupled estimates of surface heat fluxes and vegetation dynamics, remotely sensed LST and fraction of photosynthetically active radiation are assimilated into a surface energy balance and a vegetation dynamics model. The application of the assimilation over West Africa shows that the scheme provides reliable estimates of important vegetation dynamics parameters that are required for understanding the role of plant phenology on surface energy balance and vice-versa.<br>by Sayed Mohyeddin Bateni.<br>Ph.D.
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13

McAtee, Brendon Kynnie. "Surface-atmosphere interactions in the thermal infrared (8 - 14um)." Curtin University of Technology, Department of Applied Physics, 2003. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=14481.

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Remote sensing of land surface temperature (LST) is a complex task. From a satellite-based perspective the radiative properties of the land surface and the atmosphere are inextricably linked. Knowledge of both is required if one is to accurately measure the temperature of the land surface from a space-borne platform. In practice, most satellite-based sensors designed to measure LST over the surface of the Earth are polar orbiting. They scan swaths of the order of 2000 km, utilizing zenith angles of observation of up to 60°. As such, satellite viewing geometry is important when comparing estimates of LST between different overpasses of the same point on the Earth's surface. In the case of the atmosphere, the optical path length through which the surfaceleaving radiance propagates increases with increasing zenith angle of observation. A longer optical path may in turn alter the relative contributions which molecular absorption and emission processes make to the radiance measured at the satellite sensor. A means of estimating the magnitudes of these radiative components in relation to the viewing geometry of the satellite needs to be developed if their impacts on the at-sensor radiance are to be accurately accounted for. The problem of accurately describing radiative transfer between the surface and the satellite sensor is further complicated by the fact that the surface-leaving radiance itself may also vary with sensor viewing geometry. Physical properties of the surface such as emissivity are known to vary as the zenith angle of observation changes. The proportions of sunlit and shaded areas with the field-of-view of the sensor may also change with viewing geometry depending on the type of cover (eg vegetation), further impacting the surface emissivity.<br>Investigation of the change in surface-leaving radiance as the zenith angle of observation varies is then also important in developing a better understanding of the radiative interaction between the land surface and the atmosphere. The work in this study investigates the atmospheric impacts using surface brightness temperature measurements from the ATSR-2 satellite sensor in combination with atmospheric profile data from radiosondes and estimates of the downwelling sky radiance made by a ground-based radiometer. A line-by-line radiative transfer model is used to model the angular impacts of the atmosphere upon the surfaceleaving radiance. Results from the modelling work show that if the magnitude of the upwelling and downwelling sky radiance and atmospheric transmittance are accurately known then the surface-emitted radiance and hence the LST may be retrieved with negligible error. Guided by the outcomes of the modelling work an atmospheric correction term is derived which accounts for absorption and emission by the atmosphere, and is based on the viewing geometry of the satellite sensor and atmospheric properties characteristic of a semi-arid field site near Alice Springs in the Northern Territory (Central Australia). Ground-based angular measurements of surface brightness temperature made by a scanning, self calibrating radiometer situated at this field site are then used to investigate how the surface-leaving radiance varies over a range of zenith angles comparable to that of the ATSR-2 satellite sensor.<br>Well defined cycles in the angular dependence of surface brightness temperature were observed on both diumal and seasonal timescales in these data. The observed cycles in surface brightness temperature are explained in terms of the interaction between the downwelling sky radiance and the angular dependence of the surface emissivity. The angular surface brightness temperature and surface emissivity information is then applied to derive an LST estimate of high accuracy (approx. 1 K at night and 1-2 K during the day), suitable for the validation of satellite-derived LST measurements. Finally, the atmospheric and land surface components of this work are combined to describe surface-atmosphere interaction at the field site. Algorithms are derived for the satellite retrieval of LST for the nadir and forward viewing geometries of the ATSR-2 sensor, based upon the cycles in the angular dependence of surface brightness temperature observed in situ and the atmospheric correction term developed from the modelling of radiative transfer in the atmosphere. A qualitative assessment of the performance of these algorithms indicates they may obtain comparable accuracy to existing dual angle algorithms (approx. 1.5 K) in the ideal case and an accuracy of 3-4 K in practice, which is limited by knowledge of atmospheric properties (eg downwelling sky radiance and atmospheric transmittance), and the surface emissivity. There are, however, strong prospects of enhanced performance given better estimates of these physical quantities, and if coefficients within the retrieval algorithms are determined over a wider range of observation zenith angles in the future.
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14

Gutmann, Ethan D. "The determination of soil hydraulic properties in land surface models from remotely sensed surface temperature." Connect to online resource, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3303868.

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15

Bobrinskaya, Maria. "Remote Sensing for Analysis of Relationships between Land Cover and Land Surface Temperature in Ten Megacities." Thesis, KTH, Geodesi och geoinformatik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-121277.

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Urbanization is one of the most significant phenomena of the anthropogenic influence on the Earth’s environment. One of the principal results of the urbanization is the creation of megacities, with their local climate and high impact on the surrounding area. The design and evolution of an urban area leads to higher absorption of solar radiation and heat storage in which is the foundation of the urban heat island phenomenon. Remote sensing data is a valuable source of information for urban climatology studies. The main objective of this thesis research is to examine the relationship between land use and land cover types and corresponding land surface temperature, as well as the urban heat island effect and changes in these factors over a 10 year period. 10 megacities around the world where included in this study namely Beijing (China), Delhi (India), Dhaka (Bangladesh), Los Angeles (USA), London (UK), Mexico City (Mexico), Moscow (Russia), New York City (USA), Sao Paulo (Brazil) and Tokyo (Japan). Landsat satellite data were used to extract land use/land cover information and their changes for the abovementioned cities. Land surface temperature was retrieved from Landsat thermal images. The relationship between land surface temperature and landuse/land-cover classes, as well as the normalized vegetation index (NDVI) was analyzed. The results indicate that land surface temperature can be related to land use/land cover classes in most cases. Vegetated and undisturbed natural areas enjoy lower surface temperature, than developed urban areas with little vegetation. However, the cities show different trends, both in terms of the size and spatial distribution of urban heat island. Also, megacities from developed countries tend to grow at a slower pace and thus face less urban heat island effects than megacities in developing countries.
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Zhong, Xinke. "Methodological developement for retrieving land surface temperature from hyperspectral thermal infrared data." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAD014/document.

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La température de surface terrestre (LST) est un paramètre important dans les systèmes climatiques. Les données infrarouge thermique (TIR) contiennent un nombre d'information de la surface terrestre et de l'atmosphère sont des sources de l'information important pour estimer la LST à l'aide de télédétection<br>Land surface temperature (LST) is an important parameter in climate systems. Hyperspectral thermal infrared (TIR) data, containing large information about the surface and the atmosphere, is an important source of information for retrieving LST by remote-sensing
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Van, den Bergh F., Wyk MA Van, Wyk BJ Van, and G. Udahemuka. "A comparison of data-driven and model-driven approaches to brightness temperature diurnal cycle interpolation." SAIEE Africa Research Journal, 2007. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001082.

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This paper presents two new schemes for interpolating missing samples in satellite diurnal temperature cycles (DTCs). The first scheme, referred to here as the cosine model, is an improvement of the model proposed in [2] and combines a cosine and exponential function for modelling the DTC. The second scheme uses the notion of a Reproducing Kernel Hilbert Space (RKHS) interpolator [1] for interpolating the missing samples. The application of RKHS interpolators to the DTC interpolation problem is novel. Results obtained by means of computer experiments are presented.
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Polanski, Thomas. "Weighting Landsat Digital Data According to Land Cover Emissivity for Surface Temperature Mapping." TopSCHOLAR®, 1995. http://digitalcommons.wku.edu/theses/918.

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Regional urban planning and natural resource management problems require efficient and accurate data concerning land use/land cover and temperature gradients for informed decision making. Remotely-sensed data provide a method for acquiring such information in a dependable and efficient manner. Regular data acquisition and a synoptic view make the Landsat Thematic Mapper (TM) an excellent resource for entities needing land cover and surface temperature information. Landsat 5 TM digital data (1985) are used to classify land cover in the vicinity of New Orleans, the study area encompassing approximately 185 square kilometers. The maximum likelihood, minimum distance to means, and the parallelepiped classifiers produce land cover classified images with highly significant differences and the maximum likelihood rule outperforms the other methods. The maximum likelihood land cover classification is used as ancillary data for the surface temperature conversions and meets the standard of 85% thematic accuracy set by the United States Geological Survey (USGS). The Landsat 5 TM thermal channel (band 6) provides exceptional spatial resolution and is an excellent tool for mapping surface temperatures. Variable emissivities of land cover types and atmospheric conditions often need to be incorporated into surface temperature calculations from TM data. The thermal channel digital counts are weighted according to land cover emissivity and converted into kinetic temperatures (atmospheric conditions are deemed negligible for the TM data) . Statistics generated and qualitative analyses demonstrate a strong relationship between surface temperatures and land cover types, allowing for the prediction of the surface temperature change that a change in land use/land cover will incur. Applications of the research include modeling and monitoring of land use/land cover in a region, urban planning, urban heat island mapping, and natural resource management/conservation.
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Zhang, Tongfei. "Land surface temperature comparison between JULES/ CHESS model output and earth observation data." Thesis, University of Reading, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590675.

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The aim of this thesis is to build a benchmarking system for the JULES (Joint UK Land Environment Simulator)/ CHESS (Hydrological and Ecological Research Support System) model land surface temperature, to identify the strengths and weakness of conducting the land surface temperature from JULES/ CHESS model; and define a number of comparisons that can effectively evaluate JULES/ CHESS output LST using Earth's observation products, including MODIS (Moderate Resolution Imaging Spectroradiometer), and AMSR-E (Advanced Microwave Scanning Radiometer - Earth Observing System) from ADAGUC (Atmospheric Data Access for the Geospatial User Community) database. Furthermore, the benchmarking system can estimate and set up thresholds of acceptable mid-match between models output and EO products identify the clues of weak LST output performance to guide future development, and ultimately enabling improve predictions of future JULES/ CHESS model LST of ecosystems and climate. Benchmarking analyses have been done for the JULES/ CHESS model. It include the comparison between LST retrieved from the EO product and JULES/ CHESS output LST that cover a range of spatial (point to UK) and temporal (hourly to monthly) scales. This study showed that Earth Observation data can be used as part of the process of assessing the performance of a global land surface model. Earth observation products are an important resource for the evaluation of large scale and surface model, and the use of EO data provided further insight into the model. Further investigation is needed to identify the source of the discrepancy between JULES/ CHESS model LST output and EO LST products, including inspection of land surface coverage type. The LST comparison studies in this thesis demonstrated some weaknesses of the model, many of which are being worked on by researchers. The results presented in this thesis are of particular relevance to JULES/ CHESS model with the EO data, but equally important, the methods outlined in this thesis could also be helpful to give more insight than traditional site-based observations. These studies could be remains independent, and use to indicate gross errors and improvements of further model development.
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Comyn-Platt, Edward Matthew. "Land surface temperature : a comparison of products from polar orbiting and geostationary satellites." Thesis, University of Leicester, 2014. http://hdl.handle.net/2381/28815.

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This thesis has investigated land surface temperature (LST) products based on data from the Advanced Along-Track Scanning Radiometer (AATSR) and the Spinning Enhanced Visible and Infrared Imager (SEVIRI). Particular attention was paid to the long-term goal of an LST retrieval which utilises the benefits of both polar orbiting and geostationary instruments, represented by AATSR and SEVIRI, respectively. This study included an assessment of several current methods of LST retrieval, all of which were variations of the generalised split-window (GSW) algorithm. Satellite retrieved LST were compared with in situ observations at three validation sites in Europe and Africa. The results of the validation exercise suggested that for homogenous sites, Gobabeb and the “RMZ” farm in Namibia, the GSW algorithms met validation accuracies ±1-2.5 K. The accuracy of the GSW algorithms was significantly poorer at the heterogeneous site in Evora, Portugal where daytime matchups only met validation accuracies of ±5 K. Cross-platform comparisons at and around the validation sites suggested that the products were strongly correlated for night-time matchups at all sites. The daytime matchups showed greater levels of discrepancy between instruments given the combined effects of viewing geometry and sunlit/sunshade fraction observed by the satellite instruments. A novel optimal estimation (OE) method of LST retrieval has been proposed within the 1DVar framework. 1DVar is a stand-alone OE model which is based on the same architecture as 3D/4DVar systems used in a number of numerical weather prediction (NWP) and climatic models. A full diagnostic assessment of the 1DVar OE system has been presented with respect to the quality of the retrieved LST estimate based on AATSR and SEVIRI data. This demonstrated that the 1DVar OE system could reduce the LST error to 5-20% of the error associated with a priori LST estimate for both AATSR and SEVIRI. However, the implementation of the 1DVar scheme was hindered by the lack of a reliable emissivity resource; hence much of the gain in precision was compromised to the propagated emissivity error. Validation and verification of the 1DVar OE system using real data was presented in Chapter 6 of this thesis. The comparisons with in situ observations suggested only marginal improvements from the performance of the GSW products. However, the residual brightness temperatures were in much closer agreement with observations, hence the dataset was self-consistent which provided added confidence. Furthermore, this demonstration of a 1DVar scheme justifies the use of SEVIRI and AATSR data within a 3D/4DVar system which would facilitate combined platform LST retrieval. Cross-platform comparisons demonstrated that the largest sources of discrepancy were physical differences which were independent of algorithm. There was a strong seasonality, ~4K, in all the cross-platform comparisons with daytime data. Furthermore, there was a strong correlation between the cross-platform discrepancy and view-angle. This was highlighted as a major caveat of satellite LST products which are generally inferred as nadir observations by the end-user community. This is not the case and understanding the viewing geometry associated with satellite LST estimates is paramount to their various applications.
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21

Jesus, Bruna Luiza Pereira de. "A relação entre a temperatura radiométrica de superfície (Land Surface Temperature-LST), índice de vegetação (Normalizes Diference Vegetation Index-NDVI) e os diferentes padrões de uso da terra do município de São Paulo." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/8/8135/tde-11012016-143102/.

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Esse trabalho tem como objetivo compreender as relações entre a Land Surface Temperature (LST), Normalized Difference Vegetation Índex (NDVI) e os padrões do uso da terra do município de São Paulo no período de 1985 a 2010. Analisou-se 15 bairros, nos quais foram extraídas 45 amostras aleatórias de diferentes padrões de uso da terra; subdivididas em baixo padrão, médio padrão e médio alto padrão. Com o aporte de geotecnologia, foi feita a extração dos dados das imagens de satélite Landsat 5 (TM) e das Ortofotos do ano de 2010. O comportamento das amostras variou de acordo como os diferentes perfis dos grupos analisados. O grupo de baixo padrão foi o que apresentou as maiores amplitudes térmicas, ausência de arborização urbana atreladas a um baixo padrão construtivo. O grupo de médio padrão é caracterizado pela predominância de área verticalizada e apresenta uma arborização urbana escassa em meio a uma malha urbana consolidada. O grupo de médio alto padrão foi o que mais apresentou arborização urbana, distribuída de forma homogênea na maioria das amostras, portanto foi o grupo que teve baixas amplitudes térmicas e o índice de Normalized Difference Vegetation Index (NDVI) com pouca variação. Os testes mostraram fortes correlações negativas entre as amostras de Land Surface Temperature (LST) e o índice de Normalized Difference Vegetation Index (NDVI), sendo -0,58 em 1985, -0,43 em 2004 e -0,82 em 2010. Os diferentes padrões de uso da terra, relacionados à temperatura de superfície, e o índice de vegetação, aliado à preocupação com o planejamento ambiental, deve resultar na melhoria da qualidade de vida da população. Esta pesquisa faz parte do Projeto Temático processo FAPESP 08/58161 -1, \"Assessment of Impacts and Vulnerability to Climate Change in Brazil and strategies for Adaptation options\", Component 5: Vulnerability of the metropolitan region of São Paulo to climate Change.<br>This study aims to understand the relationship between Land Surface Temperature (LST), Normalized Difference Vegetation Index (NDVI) and the patterns of land use in the municipality of São Paulo, from 1985 to 2010. A totoal of 45 random samples were extracted from the 15 districts used in this study, with different patterns of land use which were subdivided into three different clases: low-end, middle and middle-high. Geospatial approaches allowed the extraction of satellite image data from Landsat 5 data (TM) and from Orthophotos from 2010. The behavior of the samples varied accordingly to the different group profiles. The low-end group presented the highest thermal amplitudes and more significant absence of urban vegetation linked, both to low urbanization and construction standards. The average standard group is characterized by the predominance of vertical buildings and lacks urban trees amidst a consolidated urban landscape. The average-high standard group displayed the highest concentration of green urban areas, distributed homogeneously in most samples, so this group presented low variations both in temperature amplitude and in the Normalized Difference Vegetation Index (NDVI). The correlation tests showed strong negative correlations between samples of Land Surface Temperature (LST) and the NDVI samples, of -0.58 in 1985, -0.43 in 2004 and -0.82 in 2010. Understanding the relations between the different patterns of land use, surface temperature and the NDVI (with due concern for environmental planning) is an important step in the identification and rehabilitation of enviromentally. This research is part of the Thematic Project FAPESP 08/58161 -1 process, \"Assessment of Impacts and Vulnerability to Climate Change in Brazil and strategies for Adaptation options\", Component 5: Vulnerability of the metropolitan region of São Paulo to climate Change.
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22

Sgoff, Christine [Verfasser], Juerg [Gutachter] Schmidli, and Roland [Gutachter] Potthast. "Assimilating synthetic land surface temperature in a fully coupled land-atmosphere system / Christine Sgoff ; Gutachter: Juerg Schmidli, Roland Potthast." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2021. http://nbn-resolving.de/urn:nbn:de:hebis:30:3-613301.

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23

Ren, Huazhong. "Modelling of directional thermal radiation and angular correction on land surface temperature from space." Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-00967047.

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The aim of this thesis is the modeling of surface directional thermal radiation and angular correction on the LST by using empirical and physical methods as well as the analysis of field validation. The work has conducted to some conclusions. The directional emissivity of natural surfaces was obtained from MODIS emissivity product and then used in the split-window algorithm for angular correction on LST. The parameterization models of directional emissivity and thermal radiation were developed. As for the non-isothermal pixels, the daytime-TISI method was proposed to retrieve directional emissivity and effective temperature from multi-angular middle and thermal infrared data. This was validated using an airborne dataset. The kernel-driven BRDF model was checked in the thermal infrared domain and its extension was used to make angular normalization on the LST. A new model, namely FovMod that concerns on the footprint of ground sensor, was developed to simulate directional brightness temperature of row crop canopy. Based on simulation result of the FovMod, an optimal footprintfor field validation of LST was obtained. This thesis has systematically investigated the topic of directional thermal radiation and angular correction on surface temperature and its findings will improve the retrieval accuracy of temperature and emissivity from remotely sensed data and will also provide suggestion for the future design of airborne or spaceborne multi-angular thermal infrared sensors and also for the ground measurement of surface parameters.
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24

Feng, Xiao. "Enhancing the spatial resolution of satellite-derived land surface temperature mapping for urban areas." Thesis, University of Nottingham, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.718459.

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Land surface temperature (LST) is an important environmental variable for urban studies such as those focused on the urban heat island (UHI). Though satellite-derived LST could be a useful complement to traditional LST data sources, the spatial resolution of the thermal sensors limits the utility of remotely sensed thermal data. To balance the trade-off between the spatial and temporal resolutions of the current satellite-derived thermal data, thermal sharpening technology is developed. However, the existing thermal sharpening methods suffer from many limitations. In this study, a thermal sharpening technique, called Super-Resolution Thermal Sharpener (SRTS), is proposed which could enhance the spatial resolution of satellite-derived LST based on super-resolution mapping (SRM) and super-resolution reconstruction (SRR). This method overcomes the limitation of traditional thermal image sharpeners that require fine spatial resolution images for resolution enhancement. Furthermore, environmental studies such as UHI modelling typically use statistical methods which require the input variables to be independent, which means the input LST and other indices should be uncorrelated. The proposed SRTS does not rely on any surface index, ensuring that the derived LST is as independent as possible from the other variables that UHI modelling often requires. To validate the SRTS, its performance is compared against that of four popular thermal sharpeners: one called TsHARP (which is not an abbreviation), adjusted stratified stepwise regression method (Stepwise), pixel block intensity modulation (PBIM), and emissivity modulation (EM), and using two types of data: MODIS and Landsat imagery which can be the representatives of coarse and medium spatial resolution data sources, respectively. The advantage of using the combination of SRR and SRM was also verified by comparing the accuracy of SRTS with a sharpening process only based on SRM or SRR. The results show that the SRTS can enhance the spatial resolution of LST with a magnitude of accuracy that is equal or even superior to other thermal sharpeners, despite not requiring fine spatial resolution input. This shows the potential of SRTS for application in conditions where only limited meteorological data sources are available yet where fine spatial resolution LST is desirable.
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Sayão, Veridiana Maria. "Land surface temperature and reflectance spectra integration obtained from Landsat on the soil attributes quantification." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-20032018-112133/.

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Soil attributes directly influence on its surface temperature. Although there are several studies using soil spectra obtained from satellites, soil evaluation through Land Surface Temperature (LST) is still scarce. The broad availability of satellite thermal data and the development of algorithms to retrieve LST facilitated its use in soil studies. The objective of this study was to evaluate soil LST variations due to its composition and verify the potential of using LST on soil attributes quantification, also integrated with reflectance spectra and elevation data. The study area (198 ha) is located in Sao Paulo state, Brazil, and had plowed bare soil during the satellite image acquisition date. Soil samples were collected in a regular grid of 100 x 100 m (depths: 0-0.2 m and 0.8- 1.0 m); soil granulometry, organic matter (OM) and iron oxides were determined by wet chemistry analysis. In this study, an image of Landsat 5 was used for extracting LST using the inversion of Planck\'s function in band 6 (10,400 - 12,500 nm), and land surface emissivity was estimated using Normalized Difference Vegetation Index threshold method. Reflectance values were extracted from bands 1, 2, 3, 4, 5 and 7. Models for soil attributes quantification were performed using Linear Regression (LR), with samples from 62 auger points distributed in 14 toposequences. Simple LR was applied for generating prediction models based on LST and on elevation data (extracted from a Digital Elevation Model). Multiple LR was applied in order to generate prediction models using atmospherically corrected spectral reflectance from Visible, Near-Infrared and Shortwave infrared (Vis-NIR-SWIR) bands as predictors, and also for the prediction of soil attributes using simultaneously Vis-NIR-SWIR, LST and elevation data, and only significant variables identified by T-tests were used. Predictive performance of models was assessed based on adjusted coefficient of determination (R2adj), Root Mean Squared Error (RMSE, g kg-1) and Ratio of Performance to Interquartile Range (RPIQ) obtained in validation. Ordinary kriging was also performed and the resulted interpolated surfaces were compared to the maps obtained from the best LR model. There was significant correlation between soil attributes and reflectance, LST and elevation data, and soils with clay texture were differentiated from sandy soils based on LST mean values. For all soil attributes, models using only elevation presented the worst performance; models using only LST, moderate performance; and using Vis-NIR-SWIR bands, good predictive performance. For clay, the best model obtained had bands 4-7, LST and elevation as predictors; for sand and iron oxides, the best model had bands 4-7 and LST; for OM, band 4, band 7 and LST. The use of LST for estimating soil attributes increases the predictive performance of multiple LR models when associated with other variables obtained through remote sensing, particularly surface reflectance data, improving the validation of models reaching high R2adj, high RPIQ and low RMSE values. Maps for sand, OM and iron oxides obtained through ordinary kriging outperformed those obtained for the same attributes using LR models based on RS co-variables, and for clay, both approaches reached the same accuracy level. Mapping of soil clay, sand, OM and iron oxides contents through multiple LR models using Landsat 5 products is a simple and easy to reproduce technique, appropriate for soil attributes mapping in bare soil agricultural areas.<br>Os atributos do solo influenciam diretamente na sua temperatura de superfície. Apesar de existir vários estudos utilizando espectros de solos obtidos de satélite, a avaliação do solo por meio da Temperatura de Superfície Terrestre (em inglês Land Surface Temperature, LST) ainda é escassa. A ampla disponibilidade de dados termais de satélite e o desenvolvimento de algoritmos para derivar a LST facilitou o seu uso em estudos de solos. O objetivo desse trabalho foi avaliar variações da LST do solo devidas à sua composição e verificar o potencial de uso da LST na quantificação de atributos do solo, também integrada com dados de espectros de reflectância e elevação. A área de estudo (198 ha) está localizada no estado de São Paulo, Brasil, e estava com solo exposto e arado na data de aquisição da imagem de satélite. Amostras de solo foram coletadas em um grid regular de 100 x 100 m (profundidades: 0.02 m e 0.8-1.0 m); a granulometria do solo, matéria orgânica (MO) e óxidos de ferro foram determinados via análises físicas e químicas laboratoriais. Neste estudo, uma imagem do Landsat 5 foi utilizada para extrair a temperatura de superfície usando a inversão da função da Lei de Planck na banda 6 (10.400 - 12.500 nm), e a emissividade de superfície foi estimada utilizando o método do limiar do Índice de Vegetação da Diferença Normalizada. Valores de reflectância das bandas 1, 2, 3, 4, 5 e 7 foram extraídos. Modelos para quantificação de atributos do solo foram feitos usando Regressão Linear (RL), com amostras de 62 pontos de tradagem distribuídos em 14 topossequências. A RL simples foi aplicada para gerar modelos de predição baseados na LST e também na elevação (extraída de um modelo digital de elevação). A RL múltipla foi aplicada para gerar modelos de predição usando os espectros de reflectância com correção atmosférica das bandas do Visível, Infravermelho próximo e Infravermelho de ondas curtas (Vis-NIR-SWIR) como preditores; também foi aplicada para predição de atributos do solo usando simultaneamente dados do Vis-NIR-SWIR, LST e elevação, e apenas variáveis significativas identificadas por teste T foram usadas. A performance preditiva dos modelos foi avaliada baseada no coeficiente de determinação ajustado (R2adj), raiz do erro quadrático médio (RMSE, g kg-1) e razão de desempenho do intervalo interquartil (RPIQ) obtidos na validação. A krigagem ordinária também foi feita e as superfícies interpoladas resultantes foram comparadas com o melhor modelo de RL. Houve correlação significativa entre os atributos do solo e dados de reflectância, LST e elevação, e solos com textura argilosa foram diferenciados de solos arenosos com base em valores médios de LST. Para todos os atributos do solo, os modelos usando apenas elevação apresentaram a pior performance, modelos usando somente LST, performance moderada, e usando as bandas do Vis-NIR-SWIR, boa performance preditiva. Para argila, o melhor modelo obtido teve as bandas 4-7, LST e elevação como preditores; para areia e óxidos de ferro, o melhor modelo teve as bandas 4-7 e LST; para MO, banda 4, banda 7 e LST. O uso da LST para estimar atributos do solo aumenta a performance preditiva de modelos de RL múltipla quando associada a outras variáveis obtidas via sensoriamento remoto (SR), particularmente dados de reflectância de superfície, melhorando a validação dos modelos atingindo altos valores de R2adj e RPIQ e baixos valores de RMSE. Os mapas para areia, MO e óxidos de ferro obtidos via krigagem ordinária superaram aqueles obtidos para os mesmos atributos usando modelos de RL baseados em co-variáveis obtidas via SR, e para argila, ambas abordagens atingiram o mesmo nível de acurácia. O mapeamento dos conteúdos de argila, areia, matéria orgânica e óxidos de ferro do solo via modelos de RL múltipla utilizando produtos do Landsat 5 é uma técnica simples e fácil de reproduzir, apropriada para o mapeamento de atributos do solo em áreas de agricultura com solo exposto.
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Pereira, Clarissa Cardoso. "Temperatura de superfície na bacia da Usina Hidrelétrica (UHE) barra dos coqueiros, utilizando climatologia e sensoriamento remoto." Universidade Federal de Goiás, 2014. http://repositorio.bc.ufg.br/tede/handle/tede/5304.

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Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-03-04T13:10:10Z No. of bitstreams: 2 Dissertação - Clarissa Cardoso Pereira - 2014.pdf: 4357036 bytes, checksum: d6e8d143c8c9748d4f1496117369cbca (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5)<br>Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-03-04T13:19:58Z (GMT) No. of bitstreams: 2 Dissertação - Clarissa Cardoso Pereira - 2014.pdf: 4357036 bytes, checksum: d6e8d143c8c9748d4f1496117369cbca (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5)<br>Made available in DSpace on 2016-03-04T13:19:58Z (GMT). No. of bitstreams: 2 Dissertação - Clarissa Cardoso Pereira - 2014.pdf: 4357036 bytes, checksum: d6e8d143c8c9748d4f1496117369cbca (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-04-14<br>Land-use change is a major contributor to environmental impacts that, among others, stand out the changes in the earth’s surface temperature condition as well as in the atmosphere that influence the climate conditions. Through the changes in the land use due to demands for areas dedicated to livestock and agriculture in the Rio Claro basin (GO), an area of study, the aim of this research was to analyze the surface temperature (ST) in the various uses of the land in the basin of Barra dos Coqueiros Hydroelectric Power Plant (HPP).The land use and the estimated ST was performed from the Landsat 5 image (bands 3, 4, 5 and 6), on April/17th/2011 and September/8th/2011, respectively representative of the wet and dry seasons. For the mapping of land use, the software ArcGIS ® 10 has been resorted. The ST was calculated using Lucena’s methodology (2012), with some adaptations concerning climatic data (temperature and relative humidity of the air) and the data concerning surface emissivity. The climatic data were collected through thermo-hygrometers, where the average temperature and average relative humidity of the air were used in order to obtain the ST and the instantaneous temperature of the air so that it was possible to compare with the values of the ST. For the dry season, 6 different uses (pastures, forests, agriculture, water, cerrado and urban areas) were identified, and the same uses were found for the wet season, though with differences in the number of areas of pastures that decreased and the areas of cerrado and forest that grew in relation to the other period. The ST in the wet period showed two ranges of ST, between 10.0 ºC and 45.0 ºC, in which the mild ST showed up in the lake areas and the high ST predominated in the urban area. As for the ST in the dry period, with a break between 10.0 ºC and 50.0 °C milder values were visible in flooded area of the reservoir and higher ones are visible in areas of exposed soil. In the analysis of the ST with the instantaneous air temperature (AT), it was found that all collection points highlight the ST in the range of 20.0 ºC and 35.0ºC, for the wet season, especially in P1 and P8 that there are higher values of ST (around 35.0 °C), since the other points, including the P6 with the lesser value of AT, the ST is milder (<30.0 °C).In the dry period, among the highest points of the ST, P1 (35.0 °C) is higher than the value of AT (34.9 °C). The P6, another point with high ST stands out from the others due to its higher AT (38.9 ºC). The behavior in the dry warmer period of the ST (25.0 º C to 35.0 º C), the P2 is the point that the ST is the mildest (25.0 °C) and the others (P3, P5, P7 and P9) the ST is 30.0 ºC. It was found in this research that the ST has presented spatial variability depending on the different land uses and temporal variability in dry and wet season, due to the condition of the vegetation.<br>Mudança no uso da terra é um dos principais responsáveis por impactos ambientais, e que dentre estes se destacam as alterações na condição da temperatura superficial terrestre e na atmosfera que influenciam as condições climáticas. Mediante as modificações do uso da terra devido às demandas por áreas para pecuária e agricultura na bacia do Rio Claro (GO), área de estudo, o objetivo da pesquisa foi analisar a temperatura de superfície (TS) nos diferentes usos da terra da bacia da Usina Hidrelétrica (UHE) Barra dos Coqueiros. O uso da terra e estimativa da TS foi realizada a partir da imagem do Landsat 5 (bandas 3, 4, 5 e 6), nas datas de 17/04/2011 e 08/09/2011, respectivamente representativas do período chuvoso e seco. Para o mapeamento do uso da terra recorreu-se ao software ArcGis® 10. A TS foi calculada a partir da metodologia de Lucena (2012), com algumas adaptações no que consistem aos dados climáticos (temperatura e umidade relativa do ar) e dos dados de emissividade da superfície. Os dados climáticos foram coletados por termohigrômetros, nos quais a temperatura média e umidade relativa média do ar serviram para obtenção da TS e a temperatura do ar instantânea para comparar com os valores de TS. Para o período seco, foram identificados 6 usos diferentes da terra (pastagens, matas, agricultura, água, cerrado e área urbana), sendo os mesmos usos do período chuvoso, entretanto com diferença no quantitativo das áreas de pastagens que diminuíram e as áreas de cerrado e mata que aumentaram em relação ao outro período analisado. A TS no período chuvoso apresentou dois intervalos de TS, entre 10,0 ºC e 45,0 ºC, no qual as TS amenas apresentaram-se nas áreas de lago e as TS elevadas predominaram na área urbana do município. Já a TS no período seco, com intervalo entre 10,0 ºC e 50,0 °C notam-se valores mais amenos em área alagada do reservatório e mais elevado em áreas de solo exposto. Na análise da TS com a temperatura do ar instantânea (TA), verificou-se que todos os pontos de coleta apresentam TS no intervalo de 20,0 ºC e 35,0 ºC, para o período chuvoso, com destaque para P1 e P8 em que há maiores valores de TS (entorno de 35,0 °C), já os demais pontos, inclusive o P6 com o menor valor de TA, a TS é mais amena (<30,0 ºC). No período seco, dentre os pontos de TS mais elevados, o P1 (35,0 ºC) mais elevado do que o valor de TA (34,9 ºC). O P6, outro ponto com TS elevado se destaca dos demais por apresentar TA mais elevada (38,9 ºC). O comportamento no período seco TS mais amenos (de 25,0 ºC a 35,0 ºC), P2 é o ponto que a TS é a mais amena (25,0 ºC) e os demais (P3, P5, P7 e P9) com TS 30,0 ºC. Constatou-se nesta pesquisa que a TS apresentou comportamento espacial de acordo com os diferentes usos da terra e comportamento temporal no período seco e chuvoso, devido às condições da vegetação.
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27

SILVA, Ana Paula Nunes da. "Ilha de calor urbana: diagnóstico e impactos no microclima da região metropolitana de Macapá, AP." Universidade Federal de Campina Grande, 2016. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/1601.

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Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-08-30T13:43:17Z No. of bitstreams: 1 ANA PAULA NUNES DA SILVA - TESE (PPGMet) 2016.pdf: 25525790 bytes, checksum: 973f4462b19d6c6616cfec5845906a37 (MD5)<br>Made available in DSpace on 2018-08-30T13:43:17Z (GMT). No. of bitstreams: 1 ANA PAULA NUNES DA SILVA - TESE (PPGMet) 2016.pdf: 25525790 bytes, checksum: 973f4462b19d6c6616cfec5845906a37 (MD5) Previous issue date: 2016-05-06<br>CNPq<br>O objetivo deste trabalho foi verificar a ocorrência de ilha de calor urbana (ICU) e sua influência no microclima na Região Metropolitana de Macapá (RMM), situada no Nordeste da Amazônia Legal, já que esta região vem apresentando um rápido processo de urbanização. Este processo de crescimento urbano provoca mudanças na cobertura e uso do solo, que podem modificar diretamente o balanço de energia em superfície gerando modificações na atmosfera que podem variar da escala local até a regional. Para verificar o crescimento urbano da RMM utilizou-se imagens do LANDSAT TM e OLI/TIRS de cinco diferentes épocas e através da classificação supervisionada MAXVER, verificou-se a expansão da classe área construída entre 1986 e 2015, classe que subentende a malha urbana. Uma análise climática com dados de precipitação e temperatura, permitiu verificar que possivelmente a variabilidade da temperatura e precipitação encontrada deve estar mais associado com eventos como El Niño do que com mudanças climáticas, entretanto, as tendências de aquecimento observadas podem estar relacionadas com o crescimento urbano. Para entender os impactos do crescimento urbano na modificação do microclima da RMM analisou-se índices de extremos climáticos de duas estações meteorológicas: uma situada no perímetro urbano e outra numa área rural da RMM. Verificou-se que as maiores mudanças térmicas ocorreram na área mais afastada da cidade, fato devido às mudanças de uso do solo na região periférica da RMM, enquanto que os índices relacionados a precipitação foram mais significativos na área urbana. Foram instalados termo-higrômetros em quatro pontos da RMM em áreas suburbanas e rurais para analisar os índices ICU, verificou-se que o índice sazonal de ICU foi maior (menor) nos meses de março a abril (outubro a dezembro), enquanto o índice horário obteve diferentes resultados de acordo com a época do ano: no mês chuvoso (seco) foi mais intenso no início da noite (do dia) com valor para a RMM atingiram valores máximos de 6°C (4,9°C). Na análise da Ilha de Calor Urbana em Superfície (ICUS) utilizaram-se cinco imagens de satélite e se verificou que em todas as imagens houve a comprovação de ICUS com núcleos nos centros da malhas urbanas das duas cidades da RMM e num distrito situado entre os dois centros urbanos analisados. Verificando os índices de conforto térmico gerados pela formação de ICU na RMM, comprovou-se que a região central da RMM apresenta os maiores valores e, que os índices de calor e de temperatura efetiva apresentaram boa relação com a percepção térmica da população de RMM, entrando o índice de conforto humano não se mostrou aplicabilidade na região em estudo.<br>The goal of the this Doctoral Thesis is to verify the occurrence of the Urban Heat Island (UHI) in the Macapá Metropolitan Area (RMM) Micro climate, which is placed in the Legal Amazon Northeast, due to the fact of the fast urbanization of the area. The development of the urban areas causes changes on the cover and use of the soil which could have a direct effect on the surface energy balance that may result in atmospheric modification in a local, or even regional,scale. In order to verify the RMM urban development, were used images from LANDSAT TM and OLI/TIRS of five different periods. Therefore, through the supervised classification MAXVER, it was possible to verify a expansion of the build-up area, the class of soil that covers the urban sheet, between 1986 and 2015. A climatic Analysis containing precipitation and temperature data showed that, probably, the variation of precipitation and temperature which appeared in the numbers presented are more likely to be associated with specific events, e.g. El Niño, than with the climatic changes. How ever, the growing heat trend observed during the research may be related to the urban development. In order to understand the impact of the development of the urban areas in the modification of the RMM micro climate, extreme climatic levels from two meteorologic bases were adopted: one of the those was placed within the urban perimeter; while the other was located in the RMM rural area. The data collected showed the biggest thermal changes took place further from the city, due to changes in the use of the soil in the isolated region of the RMM. About the levels related to precipitation, they were more significant in the urban areas. Term-hygrometers were installed in four different spots of the RMM, in suburban and rural areas, with the objective of analyzing the UHI levels. It was possible to verify that the season UHI levels were bigger (smaller) between March and April (October and December). The schedule levels showed different results along the year: during the rainy month (dry) it was more intense in the beginning of night (day) reaching maximum levels, in the RMM, of 6.0ºC (4.9ºC). For the analysis of the Urban Heat Island on Surface (SUHI) 5 satellite images were used and it was possible to verify in all of them the existence of ICUS with their cores located in the center of the urban sheets of the two cities that form the RMM and in a district placed between them. Trough the verification of the heat levels generated by the UHI formation in the RMM, it was possible to probe that the central area of the RMM presents the biggest values, and the IC and ITE levels are well connected to the RMM population's thermal perception. Considering the ICH it was evident the applicability of this Thesis in the area of the research.
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28

Gustafsson, David. "Land surface heat exchange over snow and frozen soil." Licentiate thesis, KTH, Land and Water Resources Engineering, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1231.

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<p>The energy exchange in the soil-snow-vegetation-atmospheresystem was studied to improve the quantitative knowledge of thegoverning processes. The lack of such knowledge contributes tothe uncertainty in the applicability of many existing modelsindependent of the temporal or spatial scale. The theoreticalbackground and available methods for measurements and numericalsimulations were reviewed. Numerical simulation models andavailable data sets representing open land and boreal forestwere evaluated in both diurnal and seasonal time-scales.Surface heat fluxes, snow depth, soil temperatures andmeteorological conditions were measured at an agriculturalfield in central Sweden over two winters, 1997-1999. Twoone-dimensional simulation models of different complexity wereused to simulate the heat and water transfer in thesoil-snow-atmosphere system and compared with the measurements.Comparison of simulated and observed heat fluxes showed thatparameter values governing the upper boundary condition weremore important than the formulation of the internal mass andheat balance of the snow cover. The models were useful toevaluate the lack of energy balance closure in the observedsurface heat fluxes, which underlined the importance ofimproved accuracy in eddy correlation measurements of latentflow during winter conditions.</p><p>The representation of boreal forest in the land surfacescheme used within a weather forecast model was tested with athree-year data set from the NOPEX forest site in centralSweden. The formulation with separate energy balances forvegetation and the soil/snow beneath tree cover improvedsimulation of the seasonal and diurnal variations of latent andsensible heat flux compared with an older model version.Further improvements of simulated surface heat fluxes could beexpected if the variation of vegetation properties within andbetween years and a new formulation of the boundary conditionsfor heat flux into the soil is included.</p><p><strong>Keywords</strong>: Surface energy balance, Snow, Boreal forest,SVAT models, Eddy-correlation Measurements, Latent heat flux,Sensible heat flux, Net radiation, Soil temperature,Aerodynamic roughness, Surface resistance</p><br>QC 20100614
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29

Hong, Xin. "Exploring the Influence of Urban Land Use and Land Cover Change on Land Surface Temperature Using Remote Sensing: A Case Study of Cuyahoga County, OH." Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1463136423.

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30

Dash, Prasanjit [Verfasser]. "Land surface temperature and emissivity retrieval from satellite measurements / Forschungszentrum Karlsruhe GmbH, Karlsruhe. Prasanjit Dash." Karlsruhe : FZKA, 2005. http://d-nb.info/97521960X/34.

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31

Jahan, Kazi Nusrat. "Spatial Analysis of Transect Zone and Land Surface Temperature: A Case Study on Hamilton County, Ohio." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1377873782.

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32

Phan, Thanh Noi [Verfasser], Martin [Akademischer Betreuer] Kappas, Martin [Gutachter] Kappas, et al. "Air Surface Temperature Estimation Using MODIS Land Surface Temperature Data in Northwest Vietnam / Thanh Noi Phan ; Gutachter: Martin Kappas, Gerhard Gerold, Christoph Dittrich, Heiko Faust, Daniela Sauer ; Betreuer: Martin Kappas." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/1191988937/34.

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33

Phan, Thanh Noi Verfasser], Martin [Akademischer Betreuer] Kappas, Martin [Gutachter] Kappas, et al. "Air Surface Temperature Estimation Using MODIS Land Surface Temperature Data in Northwest Vietnam / Thanh Noi Phan ; Gutachter: Martin Kappas, Gerhard Gerold, Christoph Dittrich, Heiko Faust, Daniela Sauer ; Betreuer: Martin Kappas." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://nbn-resolving.de/urn:nbn:de:gbv:7-21.11130/00-1735-0000-0003-C17B-9-5.

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34

Weber, Nadine. "Meso- und mikroskalige Untersuchungen der Landoberflächentemperaturen von Berlin." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 2009. http://dx.doi.org/10.18452/15972.

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Städtische Gebiete unterscheiden sich von Flächen mit ruraler Prägung, im Ergebnis sind sie stark modifiziert bezüglich ihrer Strahlungs- und Energiebilanz. In der vorliegenden Arbeit werden die Oberflächentemperaturen der Metropole Berlin im Mesomaßstab, unter Verwendung von Satellitenaufnahmen der ASTER- und Landsat-5- und 7-Sensoren untersucht sowie durch zusätzliche Messungen mit einer Thermalbildkamera über einen Zeitraum von 17 Monaten im Mikromaßstab erweitert. Diese Daten kombiniert mit GIS-basierten Informationen über die Landnutzungs- und Strukturtypen werden für die Analyse der räumlichen und zeitlichen Verteilung der Oberflächentemperaturen genutzt ebenso wie zur Ermittlung funktioneller Beziehungen zwischen dem thermischen Verhalten der Oberflächen und der zugehörigen Stadtstruktur. Bei der Auswertung geht es vorrangig um physikalische Prozesse und Eigenschaften, die einen Einfluss auf energetische Flüsse und ihre Interaktion mit städtischen Oberflächen haben. Eine thermische Charakteristik einzelner Bezirke über verschiedene Nutzungsklassen bis hin zu einzelnen Materialien wird erstellt. Dabei sind Temperaturdifferenzen von mehreren zehntel Kelvin zwischen den typischen städtischen Oberflächen Dächern und Rasenflächen zu beobachten. Die Resultate zeigen, dass die Verteilung der LST sehr verschieden ist und stark korreliert mit den Landbedeckungen. Es wird dargestellt, welche Stadtstrukturen besonders thermisch belastet sind, welche individuelle thermische Bedeutung einzelne Materialien haben. Besonderes Augenmerk wird auf Möglichkeiten der Beeinflussung durch Abschattung gelegt. Durch Verschattung können Differenzen der Oberflächentemperaturen von mehr als 10 Kelvin erreicht werden. Abschließend werden Modellierungen zur Verifizierung der Kameramessungen sowie zum Aufzeigen des Einflusses minimaler Änderungen in kleinräumigen Klimaten genutzt.<br>Urban areas differ from surfaces of rural character. They are very modified in their radiation- and energy balance. In this study land-surface temperatures of the city of Berlin are analyzed with the help of satellite pictures of the ASTER- and Landsat-5 and -7 sensors in mesoscale and then extended by extra measurements of an infrared camera in microscale over the course of 17 months. This data combined with GIS based information on different land use and -structures are used for the analysis of spatial and time distribution, as well as for the determination of functional relations between thermal behaviour of surfaces and the related urban structures. The evaluation mainly deals with physical processes and properties that have an influence on energetic flows and their interactions with urban surfaces. A thermal characteristic of individual districts, from different land use classes to specific materials is being created. In this there are differences in temperature of several tenths Kelvin between the typical urban surfaces of roofs and grass areas visible. The results show that the distribution of the LST varies immensely and correlates with the land coverage. It is shown, what urban structures are most thermic burdened, what individual significance specific materials have. Special attention is paid to the different possibilities of the influence through shadow. It is possible to reach a difference of surface temperatures of more than 10 Kelvin by shadow. At the end models with the 3-dimensional ENVImet are used to verify the camera measurements as well as to show the influence of minimal changes in microscale climate.
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35

Malbéteau, Yoann. "Suivi des ressources en eau par une approche combinant la télédétection multi-capteur et la modélisation phénoménologique." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30193/document.

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Ces travaux ont pour objectif général d'améliorer la représentation spatio-temporelle des processus hydrologiques de surface à partir de modèles dont la complexité est adaptée aux informations disponibles par la télédétection multi-capteur/multi-résolution. Nous avons poursuivi des développements méthodologiques (désagrégation, assimilation, modélisation du bilan d'énergie) autour de l'estimation de l'humidité du sol dans le contexte de la gestion des ressources en eau dans les régions semi-arides. Récemment, des missions spatiales permettent d'observer l'humidité des sols en surface; notamment avec le capteur AMSR-E (Advanced Microwave Scanning Radiometer-EOS) et la mission SMOS (Soil Moisture Ocean Salinity). Toutefois la résolution spatiale de ces capteurs est trop large (&gt; 40 km) pour des applications hydrologiques. Afin de résoudre le problème d'échelle, l'algorithme de désagrégation DisPATCh (Disaggregation based on Physical and Theoretical Scale Change) a été développé en se basant sur un modèle d'évapotranspiration. Dans la première partie de thèse, l'algorithme est appliqué et validé sur le bassin du Murrumbidgee (sud-est de l'Australie) avec une résolution spatiale cible de 1 km à partir des données de LST (Température de surface) et NDVI (indice de végétation) issues de MODIS (MODerate resolution Imaging Spectroradiometer) et de deux produits d'humidité du sol basse résolution : SMOS et AMSR-E. Les résultats montrent que la désagrégation est plus efficace en été, où la performance du modèle d'évapotranspiration est optimale. L'étude précédente a notamment mis en évidence que la résolution temporelle des données DisPATCh est limitée par la couverture nuageuse visible sur les images MODIS et la résolution temporelle des radiomètres micro-ondes (3 jours pour SMOS). Dans la deuxième partie, une nouvelle approche est donc développée pour assurer la continuité temporelle des données d'humidité de surface en assimilant les données DisPATCh dans un modèle dynamique de type force-restore, forcé par des données météorologiques issus de ré-analyses, dont les précipitations. La méthode combine de manière originale un système variationnel (2D-VAR) pour estimer l'humidité du sol en zone racinaire et une approche séquentielle (filtre de Kalman simplifié) pour analyser l'humidité du sol en surface. La performance de l'approche est évaluée sur deux zones: la région Tensift-Haouz au Maroc et la région de Yanco en Australie. Les résultats montrent que le couplage désagrégation/assimilation de l'humidité du sol est un outil performant pour estimer l'humidité en surface à l'échelle journalière, même lorsque les données météorologiques sont incertaines. Dans la troisième partie, une méthode de correction des effets topographiques sur la LST est développée dans le but d'étendre l'applicabilité de DisPATCh aux zones vallonnées ou montagneuses qui jouent souvent le rôle de château d'eau sur les régions semi-arides. Cette approche, basée sur un modèle de bilan d'énergie à base physique, est testée avec les données ASTER (Advanced Spaceborne Thermal Emission Reflection Radiometer) et Landsat sur la vallée d'Imlil dans le Haut Atlas Marocain. Les résultats indiquent que les effets topographiques ont été fortement réduits sur les images de LST à ~100 m de résolution et que la LST corrigée pourrait être utilisée comme une signature de l'état hydrique en montagne. Les perspectives ouvertes par ces travaux concernent la correction/désagrégation des données de précipitations et l'estimation des apports par l'irrigation pour une gestion optimisée de l'eau<br>This thesis aims to improve the spatio-temporal resolution of surface water fluxes at the land surface-atmosphere interface based on appropriate models that rely on readily available multi-sensor remote sensing data. This work has been set up to further develop (disaggregation, assimilation, energy balance modeling) approaches related to soil moisture monitoring in order to optimize water management over semi-arid areas. Currently, the near surface soil moisture data sets available at global scale have a spatial resolution that is too coarse for hydrological applications. Especially, the near surface soil moisture retrieved from passive microwave observations such as AMSR-E (Advanced Microwave Scanning Radiometer-EOS) and SMOS (Soil Moisture and Ocean Salinity) data have a spatial resolution of about 60 km and 40 km, respectively. In this context, the downscaling algorithm "DISaggregation based on Physical And Theoretical scale Change" (or DisPATCh) has been developed. The near surface soil moisture variability is estimate within a low resolution pixel at the targeted 1 km resolution based on an evapotranspiration model using LST (Land surface temperature) and NDVI (vegetation index) derived from MODIS (MODerate resolution Imaging Spectroradiometer) data. Within a first step, DisPATCh is applied to SMOS and AMSR-E soil moisture products over the Murrumbidgee river catchment in Southeastern Australia and is evaluated during a one-year period. It is found that the downscaling efficiency is lower in winter than during the hotter months when DisPATCh performance is optimal. However, the temporal resolution of DisPATCh data is limited by the gaps in MODIS images due to cloud cover, and by the temporal resolution of passive microwave observations (global coverage every 3 days for SMOS). The second step proposes an approach to overcome these limitations by assimilating the 1 km resolution DisPATCh data into a simple dynamic soil model forced by reanalysis meteorological data including precipitation. The original approach combines a variational scheme for root-zone soil moisture analysis and a sequential approach for the update of surface soil moisture. The performance is assessed using ground measurements of soil moisture in the Tensift-Haouz region in Morocco and the Yanco area in Australia during 2014. It is found that the downscaling/assimilation scheme is an efficient approach to estimate the dynamics of the 1 km resolution surface soil moisture at daily time scale, even when coarse scale and inaccurate meteorological data including rainfall are used. The third step presents a physically-based method to correct LST data for topographic effects in order to offer the opportunity for applying DisPATCh over mountainous areas. The approach is tested using ASTER (Advanced Spaceborne Thermal Emission Reflection Radiometer) and Landsat data over a 6 km by 6 km steep-sided area in the Moroccan Atlas. It is found that the strong correlations between LST and illumination over rugged terrain before correction are greatly reduced at ~100 m resolution after the topographic correction. Such a correction method could potentially be used as a proxy of the surface water status over mountainous terrain. This thesis opens the path for developing new remote sensing-based methods in order to retrieve water inputs -including both precipitation and irrigation- at high spatial resolution for water management
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36

Souza, Jussara Freire de. "Análise das mudanças do uso e ocupação do solo, variabilidade da temperatura e do saldo de radiação em João Pessoa-PB." Universidade Federal da Paraí­ba, 2014. http://tede.biblioteca.ufpb.br:8080/handle/tede/5538.

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Made available in DSpace on 2015-05-14T12:09:36Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 5605900 bytes, checksum: 3d25379d8d6eb2b9a5d187b806036974 (MD5) Previous issue date: 2014-05-27<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>This study analyzed the influence of the soil s usage and occupation on the surface temperature variance and on radiation balance in Joao Pessoa city. For that, it was used remote sensing techniques, Geographic Information Systems and SEBAL algorithm. For the soil s usage and occupation classification, and the determination of emissivity, albedo, NDVI, IAF and SAVI were used, and for surface temperature and radiation balance, Landsat 5-TM satellite s images was used, referring to november 5, 1991; August 26, 2006; and October 8, 2010.The usage and occupation of João Pessoa s soil analyses showed that during the years of 1991, 2006 and 2010, the city had a considerable increase of the urban mesh above herbaceous vegetation and bare soil. The surface temperature has shown greater values above urban area and bare soil on the last three years, above all on 1991 which obtained maximum temperature values, with average of 31.4°C above urban area and 31.1°C above bare soil. The radiation balance images and statistic values has shown that the highest values of Rn was founded above arboreal/shrubby vegetation and water for all the years, above all on 2010 when was obtained the highest values of Rn for all soil usages, which the averages were 717.5W/m² above water, and 703.2W/m² above arboreal/shrubby vegetation. The relationship between the albedo of soil usages (urban and herbaceous vegetation) with the temperature and radiation balance, has shown that it was satisfactory, indicating the method efficiency for estimate the quoted parameters with the targets analyzed for João Pessoa city. The temperature and radiation balance results found on this study, obtained through SEBAL and satellite images, allows to conclude that the values has shown match variances with those showed in the literature for similar soil usages<br>Este trabalho analisou a influência do uso e ocupação do solo na variabilidade da temperatura da superfície e no saldo de radiação na cidade de João Pessoa. Para tanto, foram utilizadas técnicas de sensoriamento remoto, Sistemas de Informações Geográficas e o algoritmo SEBAL. Para a classificação do uso e ocupação do solo e a determinação dos valores de emissividade, albedo, NDVI, IAF, SAVI, temperatura de superfície e saldo de radiação à superfície, foram utilizadas imagens do satélite Landsat 5-TM referente aos dias 5 de novembro de 1991, 26 de agosto de 2006 e 8 de outubro de 2010.A análise do uso e ocupação do solo da cidade de João Pessoa apontou que no decorrer dos anos de 1991, 2006 e 2010 a cidade teve um considerável crescimento da malha urbana sobre áreas de vegetação herbácea e solo exposto. A temperatura da superfície apresentou maiores valores sobre área urbana e solo exposto nos três anos, sobretudo em 1991 que obteve valores máximos de temperatura, com média de 31,4ºC sobre área urbana e de 31,1ºC sobre solo exposto. As imagens do saldo de radiação e os valores estatísticos mostraram que os maiores valores de Rn foram encontrados sobre vegetação arbórea/arbustiva e água para todos os anos, sobretudo em 2010 onde foram obtidos os maiores valores de Rn para todos os usos do solo, cujas médias foram de 717,5W/m² sobre água e 703,2W/m² sobre vegetação arbórea/arbustiva. A relação entre o albedo dos usos do solo (urbano e vegetação herbácea) com a temperatura e o saldo de radiação, mostrou-se satisfatórios, indicando a eficiência do método na estimativa dos parâmetros citados com os alvos analisados para a cidade de João Pessoa. Os resultados de temperatura e saldo de radiação encontrados nesta pesquisa, obtidos através do SEBAL e das imagens de satélite, permitem concluir que os valores apontaram variações condizentes com os apresentados na literatura para usos do solo similares
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37

Falcini, Patrick. "Analisi di immagini termiche aeree e satellitari per indagini multiscala in ambito urbano." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2007/.

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L’alta risoluzione nel telerilevamento termico (Thermal Remote Sensing) da aereo o satellitare si rivela molto importante nell’analisi del comportamento termico delle superfici, in particolare per lo studio dei fenomeni climatici locali dello spazio urbano. La stato termico dell'ambiente urbano è oggi motivo di grande interesse per ricercatori, organi istituzionali e cittadini. Uno dei maggiori campi di studio del comportamento termico urbano interessa il problema energetico: la riduzione dei consumi e delle emissioni di CO2 è un obiettivo primario da perseguire per uno sviluppo sostenibile, spesso supportato da criteri legislativi e progetti comunitari. Su scala differente e con caratteristiche differenti, un altro degli argomenti che scuote da anni e con notevole interesse la ricerca scientifica, è il fenomeno termico urbano che prende il nome di isola di calore; questa si sviluppa non solo in conseguenza al calore sensibile rilasciato da attività antropiche, ma anche a causa della sempre maggiore conversione del territorio rurale in urbanizzato (inurbamento), con conseguente riduzione del fenomeno dell’evapotraspirazione. Oggetto di questa dissertazione è lo studio del comportamento termico delle superfici in ambito urbano, sperimentato sulla città di Bologna. Il primo capitolo si interessa dei principi e delle leggi fisiche sui quali è basato il telerilevamento effettuato nelle bende spettrali dell’infrarosso termico. Viene data una definizione di temperatura radiometrica e cinematica, tra loro legate dall’emissività. Vengono esposti i concetti di risoluzione (geometrica, radiometrica, temporale e spettrale) dell’immagine termica e viene data descrizione dei principali sensori su piattaforma spaziale per l’alta risoluzione nel TIR (ASTER e Landsat). Il secondo capitolo si apre con la definizione di LST (Land Surface Temperature), parametro del terreno misurato col telerilevamento, e ne viene descritta la dipendenza dal flusso della radiazione in atmosfera e dalle condizioni di bilancio termico della superficie investigata. Per la sua determinazione vengono proposti metodi diversi in funzione del numero di osservazioni disponibili nelle diverse bande spettrali dell’IR termico. In chiusura sono discussi i parametri che ne caratterizzano la variabilità. Il capitolo terzo entra nel dettaglio del telerilevamento termico in ambito urbano, definendo il fenomeno dell’Urban Heat Island su tutti i livelli atmosferici interessati, fornendo un quadro di operabilità con gli strumenti moderni di rilievo alle differenti scale (analisi multiscala). Un esempio concreto di studio multiscala dei fenomeni termici urbani è il progetto europeo EnergyCity, volto a ridurre i consumi energetici e le emissioni di gas serra di alcune città del centro Europa. Il capitolo quarto riporta la sperimentazione condotta sull’isola di calore urbana della città di Bologna tramite immagini ASTER con risoluzione spaziale 90 m nel TIR e ricampionate a 15 m dal VIS. Lo studio dell’isola di calore si è effettuata a partire dal calcolo della Land Surface Temperature utilizzando valori di emissività derivati da classificazione delle superfici al suolo. Per la validazione dei dati, in alternativa alle stazioni di monitoraggio fisse dell’ARPA, presenti nell’area metropolitana della città, si è sperimentato l’utilizzo di data-loggers per il rilievo di temperatura con possibilità di campionamento a 2 sec. installati su veicoli mobili, strumentati con ricevitori GPS, per la misura dei profili di temperatura atmosferica near-ground lungo transetti di attraversamento della città in direzione est-ovest.
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38

Igergård, Fanny. "Addressing the urban heat island effect in Stockholm : An analysis of its presence and relation to land cover and urban planning." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-297702.

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As urbanization and global warming increase, an increasing importance is set on that urban planning processes take the possible effects of urban heat islands into account. In order to provide local city planners with site specific knowledge of the current situation in Stockholm, this study has explored the intra-urban heat island effect in Stockholm municipality by identifying major problem areas as well as addressing the statistical relationship between temperature and factors relating to land cover and urban planning strategies. Remotely sensed land surface temperature (LST) and the Swedish National Land Cover Database (NMD) have formed the data basis for the analyses that were carried out using GIS. The LST and land cover information have been extracted from randomly placed circle polygons in order to create a sample for the statistical analyses.  The results show that there exist differences in temperature within Stockholm municipality, both within the municipality as a whole and between various urban characters. In both cases, land cover is identified as an important, but not sole, factor to explain the differences. On land areas, artificial non-vegetated surfaces and forest is identified as the land cover classes of most relevance when it comes to the urban heat island effect. For both land cover classes, a strong correlation to LST is seen. Even though certain uncertainties and limitations are embedded in the data as well as in the method choices, the study can conclude in that the urban heat island effect is present in Stockholm municipality and that it can be derived from both land cover and urban characters.<br>I takt med att urbaniseringen och den globala uppvärmningen ökar kommer högre krav ställas på att stadsplaneringen tar hänsyn till de effekter som väntas uppstå kopplat till urbana värmeöar. I syfte att bistå lokala stadsplanerare med platsspecifik kunskap om den nuvarande situationen i Stockholm har den här studien utforskat intraurbana temperaturvariationer i Stockholms stad genom att identifiera de mest utsatta områdena samt genom att undersöka det statistiska sambandet mellan temperatur och faktorer kopplat till marktäcke och stadsutformning. Markens yttemperatur uppmätt från satellit och Nationella marktäckedata (NMD) har utgjort det främsta dataunderlaget för analyserna som genomförts med hjälp av GIS. Genom att extrahera information om yttemperatur och marktäcke från slumpmässigt placerade cirkelpolygoner kunde ett urval till de statistiska analyserna skapas.  Resultaten från studien visar att det finns skillnader i temperatur inom Stockholms stad, både inom kommunen som helhet och mellan olika stadsbyggnadskaraktärer. I båda fallen kan marktäcke identifieras som en viktig, men inte ensam, faktor till att förklara skillnaderna. På landområdena identifieras exploaterad mark och skog som de marktäcken med störst betydelse när det kommer till urbana värmeöar. För båda marktäckena ses i studien en stark korrelation till yttemperatur. Trots att vissa osäkerheter och begräsningar kan kopplas till både använd data och de metoder som använts kan slutsatsen att effekten från urbana värmeöar finns i Stockholms kommun dras. Dessutom kan konstateras att effekten kan härledas både till marktäcke och stadsbyggnadskaraktär.
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39

Duffour, Clément. "Analyse des effets directionnels dans l'infrarouge thermique dans le cas des couverts végétaux continus : modélisation et application à la correction des données spatiales." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30050/document.

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Les données de télédétection dans l'infrarouge thermique (IRT) sont une source indispensable d'information pour estimer les flux de surface et suivre le fonctionnement des agro-écosystèmes. Cependant, les mesures de température de surface sont sujettes à des effets directionnels très importants (présence de 'hot spot') pouvant entraîner une erreur allant jusqu'à une dizaine de degrés Celsius. Ils doivent être pris en compte en vue des applications opérationnelles. Le travail proposé ici vise à modéliser l'anisotropie directionnelle des couverts végétaux pour mettre au point des méthodes opérationnelles de correction des mesures satellitaires de température de surface. Il est largement motivé par les projets du CNES visant à élaborer une mission spatiale nouvelle combinant une haute résolution spatiale et des capacités fortes de revisite dans l'IRT. Deux étapes de travail ont été menées. La première repose sur l'utilisation du modèle déterministe de transfert Sol-Végétation-Atmosphère SCOPE (Soil Canopy Observation, Photochemistry and Energy fluxes), capable de simuler les radiances directionnelles dans l'optique et l'IRT. Dans ce manuscrit, il est validé par rapport à des mesures de terrain et sa capacité à simuler correctement les effets d'anisotropie démontrée. Il est ensuite utilisé pour étudier de façon systématique la sensibilité de l'anisotropie directionnelle à la structure de la canopée, à son état hydrique, au forçage météorologique et aux configurations angulaires solaire et de visée. Les conséquences en terme d'impact combiné des caractéristiques orbitales des satellites, de la position géographique des sites observés et de la date d'acquisition sur l'anisotropie sont discutées. La seconde étape vise à proposer un modèle paramétrique simplifié (dit RL). SCOPE est ici utilisé en tant que générateur de données. Le modèle RL se révèle robuste et capable de restituer avec succès les signatures directionnelles sur le plan géométrique (position du hot spot) comme pour l'amplitude des effets directionnels. Une comparaison avec le seul autre modèle paramétrique utilisé jusqu'alors en télédétection IRT (le modèle de Vinnikov) confirme les qualités du modèle RL, ce qui en fait un candidat potentiel pour les chaines de traitement des futures données satellitaires<br>Remotely-sensed data in thermal infrared (TIR) are an essential source of information to estimate surface fluxes and to monitor the functioning of agro-ecosystems. However, surface temperature measurements are prone to directional effects ('hot spot' phenomenon)which may result in an error up to 10°C. They have to be taken into account in the framework of operational applications. The work proposed here aims at modelling the directional anisotropy of continuous vegetated canopies in order to develop operational methods for correcting land surface temperature measurements carried out by TIR satellites. This work is mainly motivated by the CNES projects aiming at developing a new TIR spatial mission combining both high spatial resolution and high revisit time capacities. Two steps were carried out. The first is based on the use of the deterministic SVAT model SCOPE (Soil Canopy Observation, Photochemistry and Energy fluxes), able to simulate directional radiances at top of canopy in both optical and TIR domains. In this thesis, it is validated against experimental measurements and its ability to successfully simulate TIR directional anisotropy demonstrated. Then it is used to study the sensitivity of anisotropy to canopy structure, water status of soil and vegetation, meteorological forcing and solar and observer angular configurations. The consequences of the combined features of satellites orbits, geographical position of the scanned sites and acquisition date on anisotropy are discussed. In the second part, we propose a simplified parametric model (called 'RL'). SCOPE is used as a data generator. The RL model is deemed suitable and able to correctly reproduce directional signatures both in terms of geometry (hot spot position) and amplitude of these effects. A comparison with the only one parametric model previously used in TIR remote sensing (Vinnikov's approach) confirms the good capacities of the RL model. The RL model is thus a potential candidate to the future satellite processing chains
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40

Mahajan, Salil. "CCM3 as applied to an idealized all land zonally symmetric planet, Terra Blanda 3." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1422.

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Community Climate Model 3 (CCM3) is run on an idealized all land zonally symmetric planet (Terra Blanda) with no seasonality, no snow and fixed soil moisture to obtain a stationary time series effectively much longer than conventional runs with geography and seasons. The surface temperature field generated is studied to analyze the spatial and temporal spectra, estimate the length scale and time scale of the model, and test the linearity of response to periodic and steady heat source forcings. The length scale of the model is found to be in the range of 1000-2000 km and the time scale is estimated to be 24 days for the global average surface temperature field. The response of the global average temperature is found to be fairly linear to periodic and the steady heat source forcings. The results obtained are compared with the results of a similar study that used CCM0. Fluctuation Dissipation theorem is also tested for applicability on CCM3. The response of the surface temperature field to a step function forcing is demonstrated to be very similar to the decay of naturally occurring anomalies, and the auto-correlation function. Return period of surface temperature anomalies is also studied. It is observed that the length of the data obtained from CCM3, though sufficient for analysis of first and second moments, is significantly deficient for return period analysis. An AR1 process is simulated to model the global averaged surface temperature of Terra Blanda 3 to assess the sampling error associated with short runs.
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41

Mechri, Rihab. "Désagrégation spatiale de températures Météosat par une méthode d'assimilation de données (lisseur particulaire) dans un modèle de surface continentale." Thesis, Versailles-St Quentin en Yvelines, 2014. http://www.theses.fr/2014VERS0036/document.

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La température des surfaces continentales (LST) est une variable météorologiquetrès importante car elle permet l’accès aux bilans d’énergie et d’eau ducontinuum Biosphère-Atmosphère. Sa haute variabilité spatio-temporelle nécessite desmesures à haute résolution spatiale (HRS) et temporelle (HRT) pour suivre au mieuxles états hydriques du sol et des végétations.La télédétection infrarouge thermique (IRT) permet d’estimer la LST à différentesrésolutions spatio-temporelles. Toutefois, les mesures les plus fréquentes sont souventà basse résolution spatiale (BRS). Il faut donc développer des méthodes pour estimerla LST à HRS à partir des mesures IRT à BRS/HRT. Cette solution est connue sous lenom de désagrégation et fait l’objet de cette thèse.Ainsi, une nouvelle approche de désagrégation basée sur l’assimilation de données(AD) est proposée. Il s’agit de contraindre la dynamique des LSTs HRS/HRT simuléespar un modèle en minimisant l’écart entre les LST agrégées et les données IRT àBRS/HRT, sous l’hypothèse d’homogénéité de la LST par type d’occupation des sols àl’échelle du pixel BRS. La méthode d’AD choisie est un lisseur particulaire qui a étéimplémenté dans le modèle de surface SETHYS (Suivi de l’Etat Hydrique du Sol).L’approche a été évaluée dans une première étape sur des données synthétiques etvalidée ensuite sur des données réelles de télédétection sur une petite région au Sud-Est de la France. Des séries de températures Météosat à 5 km de résolution spatialeont été désagrégées à 90m et validées sur une journée à l’aide de données ASTER.Les résultats encourageants nous ont conduit à élargir la région d’étude et la périoded’assimilation à sept mois. La désagrégation des produits Météosat a été validée quantitativementà 1km à l’aide de données MODIS et qualitativement à 30m à l’aide dedonnées Landsat7. Les résultats montrent de bonnes performances avec des erreursinférieures à 2.5K sur les températures désagrégées à 1km<br>Land surface temperature (LST) is one of the most important meteorologicalvariables giving access to water and energy budgets governing the Biosphere-Atmosphere continuum. To better monitor vegetation and energy states, we need hightemporal and spatial resolution measures of LST because its high variability in spaceand time.Despite the growing availability of Thermal Infra-Red (TIR) remote sensing LSTproducts, at different spatial and temporal resolutions, both high spatial resolution(HSR) and high temporal resolution (HTR) TIR data is still not possible because ofsatellite resolutions trade-off : the most frequent LST products being low spatial resolution(LSR) ones.It is therefore necessary to develop methods to estimate HSR/HTR LST from availableTIR LSR/HTR ones. This solution is known as "downscaling" and the presentthesis proposes a new approach for downscaling LST based on Data Assimilation (DA)methods. The basic idea is to constrain HSR/HTR LST dynamics, simulated by a dynamicalmodel, through the minimization of their respective aggregated LSTs discrepancytoward LSR observations, assuming that LST is homogeneous at the land cover typescale inside the LSR pixel.Our method uses a particle smoother DA method implemented in a land surfacemodel : SETHYS model (Suivie de l’Etat Hydrique de Sol). The proposed approach hasbeen firstly evaluated in a synthetic framework then validated using actual TIR LSTover a small area in South-East of France. Meteosat LST time series were downscaledfrom 5km to 90m and validated with ASTER HSR LST over one day. The encouragingresults conducted us to expand the study area and consider a larger assimilation periodof seven months. The downscaled Meteosat LSTs were quantitatively validated at1km of spatial resolution (SR) with MODIS data and qualitatively at 30m of SR withLandsat7 data. The results demonstrated good performances with downscaling errorsless than 2.5K at MODIS scale (1km of SR)
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42

Lief, Aram P. "Spatial Analysis of Post-Hurricane Katrina Thermal Pattern and Intensity in Greater New Orleans: Implications for Urban Heat Island Research." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1820.

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In 2005, Hurricane Katrina’s diverse impacts on the Greater New Orleans area included damaged and destroyed trees, and other despoiled vegetation, which also increased the exposure of artificial and bare surfaces, known factors that contribute to the climatic phenomenon known as the urban heat island (UHI). This is an investigation of UHI in the aftermath of Hurricane Katrina, which entails the analysis of pre and post-hurricane Katrina thermal imagery of the study area, including changes to surface heat patterns and vegetative cover. Imagery from Landsat TM was used to show changes to the pattern and intensity of the UHI effect, caused by an extreme weather event. Using remote sensing visualization methods, field data, and local knowledge, the author found there was a measurable change in the pattern and intensity of the New Orleans UHI effect, as well as concomitant changes to vegetative land cover. This finding may be relevant for urban planners and citizens, especially in the context of recovery from a large-scale disaster of a coastal city, regarding future weather events, and other natural and human impacts.
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43

SANTOS, Nicali Bleyer Ferreira dos. "Padrões de distribuições espaciais e temporais de temperatura de superfície no bioma Cerrado: uma análise integrada a partir de dados orbitais de resolução moderada." Universidade Federal de Goiás, 2010. http://repositorio.bc.ufg.br/tede/handle/tde/338.

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Made available in DSpace on 2014-07-29T12:05:38Z (GMT). No. of bitstreams: 1 Nicali Bleyer Ferreira dos Santos.pdf: 4920113 bytes, checksum: a59f1d414404296c48b9a3c0454ab936 (MD5) Previous issue date: 2010-07-12<br>The occurrence of vegetation is an important factor regarding the maintainance of natural biogeochemical processes. In the Cerrado, the conversion of the vegetative cover into croplands and cultivated pasturelands has induced severe modifications in biophysical variables such as land surface temperatures, highly sensitive to land cover / land use changes. Thus, and aiming at a more complete understanding of the land conversion impacts on the Cerrado biophysical variables, in this study we assessed, through orbital data (MOD 11 product - Land Surface Temperature), the correlation between land occupation and thermal variability, considering 2003 imagery obtained at the beginning and end of the dry season. In particular, we investigated the LST behavior in relation to the major Cerrado land cover classes, as well as its response to the ongoing clearings. Our results confirmed higher temperatures over anthropic areas, as well as significant increases immediately following deforestations.<br>A presença de vegetação verde é um importante fator na manutenção de processos biogeoquímicos da natureza. No Cerrado, assim como em outros ecossistemas, a conversão da vegetação natural em áreas de pastagens e agricultura induz a alteração de variáveis biofísicas como a temperatura de superfície (TS), altamente sensível a mudanças na cobertura da terra. Dessa maneira, com vistas à cotribuir com o entendimento da dinâmica de causa e efeito do uso e ocupação da terra no Cerrado nas variáveis biofísicas da região, o presente trabalho procurou analisar, através de dados orbitais (produto MOD11-Land Surface Temperature), a correlação entre a ocupação da terra e a variabilidade termal de superfície, tendo como recorte temporal o ano de 2003 nos períodos de maio e setembro (início e final da seca). Para esse propósito, relacionaram-se as diversas formas de ocupação (expressas pelas categorias de uso e ocupação da terra) com a variável biofísica TS, bem como se verificou a variabilidade termal após episódios de desmatamento. A análise dos dados mostrou temperaturas de superfície mais elevadas em áreas antropizadas e evidenciou um aumento positivo na TS em áreas desmatadas no bioma Cerrado.
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44

Daibert, Raphael Ferreira. "Influência da temperatura e velocidade de operação no dimensionamento de pavimentos asfálticos de corredores de ônibus." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/3/3138/tde-19072016-113823/.

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No Brasil os pavimentos novos de rodovias e corredores de ônibus com tráfego pesado tem sido dimensionados empregando-se métodos empíricos e avaliados estruturalmente utilizando a análise mecanicista baseada na teoria da elasticidade. Nestes procedimentos as características de deformabilidade dos revestimentos de misturas asfálticas usualmente são consideradas fixas para uma determinada temperatura e uma velocidade de carregamento. Em campo, os pavimentos estão sujeitos a uma variedade de condições climáticas e operacionais diferentes daquelas preestabelecidas no dimensionamento. Considerando que os revestimentos asfálticos são constituídos de materiais visco-elásticos, dependentes das condições operacionais, o trabalho teve por objetivo, através de estudos paramétricos e utilizando modelos comportamentais constantes na bibliografia existente, verificar a influência da variação da temperatura e da velocidade dos veículos pesados no desempenho dos pavimentos dimensionados através dos procedimentos tradicionalmente adotados pelos principais órgãos rodoviários brasileiros. O trabalho verifica ainda, embasado na análise mecanicista, a adequabilidade estrutural das espessuras mínimas de revestimento asfáltico recomendadas pelos métodos empíricos para cada nível de solicitação do tráfego, em função de eventuais alterações nas condições climáticas e operacionais que possam ocorrer durante a vida útil do pavimento em campo.<br>In Brazil, the new highways pavements and bus lane with heavy traffics have been dimensioned by empirical methods and structurally evaluated using mechanistic elastic theory. In these procedures the characteristics of deformability of asphalt pavements courses are usually fixed to a specific temperature and loading speed. In the fields, the pavements are exposed to a variety of different climatic and operational conditions from those previous established. Considering that the asphalt layers are made from thermo-visco-elastic and depends on the operational conditions, the aim of this current study was to verify the influence of the temperature variation also the speed of heavy vehicles in the performance of pavements through procedures traditionally adopted by road agencies and parametric studies using behavioral models in existing literature. This academic work also notes, based on mechanistic criteria, structural adequacy of the asphaltic surface course minimum thickness recommended by empirical methods for each traffic demand, due to possible changes in climatic and operational conditions that may occur during the pavement area lifecycle.
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45

Sassi, Mohamed Zied. "Apport de la synergie des observations satellitaires pour la définition de la température de surface en prévision numérique." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30240.

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La modélisation des échanges radiatifs surface-atmosphère est cruciale en prévision numérique du temps. La température de surface est un paramètre clé dans cette modélisation. Sur mer, la température de surface varie sur des grandes échelles spatiales (environ 100 km) et plus lentement que sur continents, au-dessus desquels sa variabilité est beaucoup plus importante spatialement et plus rapide, ce qui rend son observation ainsi que sa prévision plus difficiles. L'évolution des techniques d'observation météorologique, notamment les satellites météorologiques, a permis de mieux observer la température de surface sur continents (LST). Toutefois, la LST n'est pas directement observée par les instruments satellitaires mais elle est restituée à partir de mesures de rayonnement au sommet de l'atmosphère. Or la LST est importante pour exploiter pleinement les luminances satellitaires dans les modèles de prévision numérique du temps. À Météo-France, l'approche adoptée pour certains instruments infrarouges consiste à utiliser, pour chaque instrument séparément, un canal fenêtre pour restituer la LST en ciel clair qui est ensuite utilisé pour l'assimilation des autres canaux de ce même instrument. Cependant, ces LST ne sont pas assimilées dans le système d'analyse de surface du modèle AROME. Ce travail de thèse consiste à étudier l'accord entre les LST restituées à partir de différents capteurs puis à évaluer l'impact de leur assimilation dans le modèle AROME [Seity et al., 2011]. Des comparaisons entre les LST restituées à partir du capteur infrarouge SEVIRI (Spinning Enhanced Visible and Infrared Imager) [Aminou, 2002] et des observations locales aux stations de Toulouse Météopole-Flux [Maurel, 2019] et d'Evora [Kabsch et al., 2008] montrent un bon accord global du cycle diurne, en particulier pendant les mois d'été. En ce qui concerne les comparaisons entre les LST restituées à partir des capteurs infrarouges SEVIRI et IASI, les différences moyennes sont de l'ordre du degré, avec des écarts-types plus faibles de nuit que de jour. Concernant les capteurs micro-ondes, les comparaisons entre les LST restituées à partir de SEVIRI et les LST de AMSU-A et MHS montrent un moins bon accord qu'entre les capteurs infrarouges, avec des écarts-types de l'ordre de 4K. En effet, les canaux fenêtre des instruments micro-ondes sont sensibles aux premiers centimètres du sol, contrairement aux capteurs infrarouges qui sont sensibles uniquement à la couche superficielle. Par la suite, des simulations de températures de brillance de plusieurs instruments utilisant des températures de surface différentes ont permis d'évaluer la pertinence des LST restituées à partir d'un capteur pour l'assimilation de canaux d'autres instruments. Ainsi, pour les capteurs infrarouges, l'utilisation d'une LST restituée à partir de SEVIRI a donné une meilleure simulation des températures de brillance de IASI par rapport à l'utilisation de la température de surface prévue par le modèle AROME. Une meilleure simulation des températures de brillance SEVIRI a été également obtenue avec la LST IASI qu'avec la température de surface prévue par AROME.[...]<br>Modeling surface-atmosphere radiative exchanges is crucial in numerical weather prediction. The surface temperature is a key parameter in this modelization. Above sea, the surface temperature varies on large space and time scales, unlike the continents above which its variability is much larger. This makes its observation and prediction more difficult. Developments in meteorological observation techniques, in particular meteorological satellites, allow to better observe the surface temperature on continents (LST). However, the LST is not directly observed by satellite instruments but it is retrieved from radiation measurements at the top of the atmosphere. However, a good LST accuracy is important for the assimilation of satellite luminances in numerical weather prediction models. At Météo-France, the adopted approach consists in using a window channel to retrieve the LST in clear sky conditions, which is then used to assimilate the other satellite channels of the infrared instruments in the model. However, these LSTs are not assimilated in the surface analysis system of the AROME model [Seity et al., 2011]. This phD work consists in studying the agreement between the LSTs retrieved from different sensors and then in evaluating the impact of their assimilation in the AROME model. Comparisons between the LSTs retrieved from SEVIRI [Aminou, 2002] and local observations from infrared sensor at the Toulouse Météopole-Flux [Maurel, 2019] and Evora [Kabsch et al., 2008] stations show a good overall agreement of the diurnal cycle description, especially during the summer months. Regarding the comparisons between the LSTs retrieved from the infrared sensors SEVIRI and IASI, the average differences are around one degree, with smaller standard deviations of differences at night-time than during daytime. Regarding microwave sensors, comparisons between LSTs retrieved from SEVIRI and LSTs from AMSU-A and MHS show less agreement than between infrared sensors, with standard deviations of the order of 4K. In fact, the window channels of microwave instruments are sensitive to the first few centimeters of the ground, unlike infrared sensors which are sensitive only to the surface skin layer. Subsequently, brightness temperature simulations of several sensors using different surface temperatures are used to assess the suitability of the LSTs retrieved from one sensor for the assimilation of channels from other instruments. For the infrared sensors, the use of an ST retrieved from SEVIRI gave a better simulation of the brightness temperatures of IASI compared to the use of the surface temperature from AROME model forecasts, and a better simulation of SEVIRI brightness temperatures was also obtained with the IASI LST than with the surface temperature from AROME forecasts. Following this preparatory study, we set up an assimilation experiment of the LSTs retrieved from SEVIRI instrument in the AROME NWP model. The assimilation of SEVIRI LSTs slightly improve the assimilation of the satellite radiances of different sensors in the atmospheric model on most analysis networks. [...]
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46

Amazirh, Abdelhakim. "Monitoring crops water needs at high spatio-temporal resolution by synergy of optical/thermal and radar observations." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30101.

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L'optimisation de la gestion de l'eau en agriculture est essentielle dans les zones semi-arides afin de préserver les ressources en eau qui sont déjà faibles et erratiques dues à des actions humaines et au changement climatique. Cette thèse vise à utiliser la synergie des observations de télédétection multispectrales (données radar, optiques et thermiques) pour un suivi à haute résolution spatio-temporelle des besoins en eau des cultures. Dans ce contexte, différentes approches utilisant divers capteurs (Landsat-7/8, Sentinel-1 et MODIS) ont été developpées pour apporter une information sur l'humidité du sol (SM) et le stress hydrique des cultures à une échelle spatio-temporelle pertinente pour la gestion de l'irrigation. Ce travail va parfaitement dans le sens des objectifs du projet REC "Root zone soil moisture Estimates at the daily and agricultural parcel scales for Crop irrigation management and water use impact: a multi-sensor remote sensing approach" (http://rec.isardsat.com/) qui visent à estimer l'humidité du sol dans la zone racinaire (RZSM) afin d'optimiser la gestion de l'eau d'irrigation. Des approches innovantes et prometteuses sont mises en place pour estimer l'évapotranspiration (ET), RZSM, la température de surface du sol (LST) et le stress hydrique de la végétation à travers des indices de SM dérivés des observations multispectrales à haute résolution spatio-temporelle. Les méthodologies proposées reposent sur des méthodes basées sur l'imagerie, la modélisation du transfert radiatif et la modélisation du bilan hydrique et d'énergie et sont appliquées dans une région à climat semi-aride (centre du Maroc). Dans le cadre de ma thèse, trois axes ont été explorés. Dans le premier axe, un indice de RZSM dérivé de LST-Landsat est utilisé pour estimer l'ET sur des parcelles de blé et des sols nus. L'estimation par modélisation de ET a été explorée en utilisant l'équation de Penman-monteith modifiée obtenue en introduisant une relation empirique simple entre la résistance de surface (rc) et l'indice de RZSM. Ce dernier est estimé à partir de la température de surface (LST) dérivée de Landsat, combinée avec les températures extrêmes (en conditions humides et sèches) simulée par un modèle de bilan d'énergie de surface piloté par le forçage météorologique et la fraction de couverture végétale dérivée de Landsat. La méthode utilisée est calibrée et validée sur deux parcelles de blé situées dans la même zone près de Marrakech au Maroc. Dans l'axe suivant, une méthode permettant de récupérer la SM de la surface (0-5 cm) à une résolution spatiale et temporelle élevée est développée à partir d'une synergie entre données radar (Sentinel-1) et thermique (Landsat) et en utilisant un modèle de bilan d'énergie du sol. L'approche développée a été validée sur des parcelles agricoles en sol nu et elle donne une estimation précise de la SM avec une différence quadratique moyenne en comparant à la SM in situ, égale à 0,03 m3 m-3. Dans le dernier axe, une nouvelle méthode est développée pour désagréger la MODIS LST de 1 km à 100 m de résolution en intégrant le SM proche de la surface dérivée des données radar Sentinel-1 et l'indice de végétation optique dérivé des observations Landsat. Le nouvel algorithme, qui inclut la rétrodiffusion S-1 en tant qu'entrée dans la désagrégation, produit des résultats plus stables et robustes au cours de l'année sélectionnée. Dont, 3,35 °C était le RMSE le plus bas et 0,75 le coefficient de corrélation le plus élevé évalués en utilisant le nouvel algorithme<br>Optimizing water management in agriculture is essential over semi-arid areas in order to preserve water resources which are already low and erratic due to human actions and climate change. This thesis aims to use the synergy of multispectral remote sensing observations (radar, optical and thermal data) for high spatio-temporal resolution monitoring of crops water needs. In this context, different approaches using various sensors (Landsat-7/8, Sentinel-1 and MODIS) have been developed to provide information on the crop Soil Moisture (SM) and water stress at a spatio-temporal scale relevant to irrigation management. This work fits well the REC "Root zone soil moisture Estimates at the daily and agricultural parcel scales for Crop irrigation management and water use impact: a multi-sensor remote sensing approach" (http://rec.isardsat.com/) project objectives, which aim to estimate the Root Zone Soil Moisture (RZSM) for optimizing the management of irrigation water. Innovative and promising approaches are set up to estimate evapotranspiration (ET), RZSM, land surface temperature (LST) and vegetation water stress through SM indices derived from multispectral observations with high spatio-temporal resolution. The proposed methodologies rely on image-based methods, radiative transfer modelling and water and energy balance modelling and are applied in a semi-arid climate region (central Morocco). In the frame of my PhD thesis, three axes have been investigated. In the first axis, a Landsat LST-derived RZSM index is used to estimate the ET over wheat parcels and bare soil. The ET modelling estimation is explored using a modified Penman-Monteith equation obtained by introducing a simple empirical relationship between surface resistance (rc) and a RZSM index. The later is estimated from Landsat-derived land surface temperature (LST) combined with the LST endmembers (in wet and dry conditions) simulated by a surface energy balance model driven by meteorological forcing and Landsat-derived fractional vegetation cover. The investigated method is calibrated and validated over two wheat parcels located in the same area near Marrakech City in Morocco. In the next axis, a method to retrieve near surface (0-5 cm) SM at high spatial and temporal resolution is developed from a synergy between radar (Sentinel-1) and thermal (Landsat) data and by using a soil energy balance model. The developed approach is validated over bare soil agricultural fields and gives an accurate estimates of near surface SM with a root mean square difference compared to in situ SM equal to 0.03 m3 m-3. In the final axis a new method is developed to disaggregate the 1 km resolution MODIS LST at 100 m resolution by integrating the near surface SM derived from Sentinel-1 radar data and the optical-vegetation index derived from Landsat observations. The new algorithm including the S-1 backscatter as input to the disaggregation, produces more stable and robust results during the selected year. Where, 3.35 °C and 0.75 were the lowest RMSE and the highest correlation coefficient assessed using the new algorithm
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47

Sabajo, Clifton. "Changements dans l’utilisation des terres et de la couverture terrestre en Asie du sud-est : les effets de la transformation sur les paramètres de la surface en Indonésie." Thesis, Paris, AgroParisTech, 2018. http://www.theses.fr/2018AGPT0005.

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Au cours des dernières décennies, l'Indonésie a connu des transformations spectaculaires des terres avec une expansion des plantations de palmiers à huile au détriment des forêts tropicales. L'Indonésie est actuellement l'une des régions ayant le plus haut taux de transformation de la surface terrestre dans le monde à cause de l'expansion des plantations de palmiers à huile et d'autres agricultures qui remplacent les forêts à grande échelle. Comme la végétation est un modificateur du climat près du sol, ces transformations à grande échelle ont des impacts majeurs sur les variables biophysiques de surface telles que la température de surface, l'albédo, les indices de végétation (NDVI), sur le bilan énergétique de surface et le partitionnement énergétique.Ce travail de thèse vise à quantifier les impacts des changements d’usage des terres en Indonésie sur les variables biophysiques de surface. Pour évaluer ces changements à l'échelle régionale, des données de télédétection sont nécessaires.Étant une variable clé de nombreuses fonctions écologiques, la température de surface (LST) est directement affectée par les changements de la couverture terrestre. Nous avons analysé la LST à partir de la bande thermique d'une image Landsat et produit une carte de température de surface avec une haute résolution (30m) pour les basses terres de la province de Jambi à Sumatra (Indonésie), une région qui a subi de grandes transformations au cours des dernières décennies. La comparaison des LST, albédo, NDVI et évapotranspiration (ET) entre sept différents types de couverture terrestre (forêts, zones urbaines, terres incultes, plantations de palmiers à huile jeunes et matures, plantations d'acacias et de caoutchouc) montre que les forêts ont des températures de surface inférieures à celles des autres types de couvert végétal, ce qui indique un effet de réchauffement local après la conversion des forêts vers des plantations. Les différences de LST atteignaient 10,1 ± 2,6 ºC (moyenne ± écart-type) entre les forêts et les terres déforestées. Les différences de températures de surface s'expliquent par un effet de refroidissement évaporatif des forêts, qui compense l'effet de réchauffement de l'albédo.Basé sur des différences observées dans les variables biophysiques entre les plantations de palmiers à huile jeunes et matures, nous avons analysé trois images Landsat couvrant une chronoséquence de plantations de palmiers à huile pour étudier la dynamique des variables biophysiques de surface pendant le cycle de rotation de 20-25 ans des plantations de palmiers à huile.Nos résultats montrent que les différences entre les plantations de palmiers à huile à différents stades du cycle de rotation du palmier à huile se reflètent dans les différences du bilan énergétique de surface, du partitionnement énergétique et des variables biophysiques. Au cours du cycle de rotation des plantations de palmiers à huile, les différences de température à la surface diminuent graduellement et se rapprochent de zéro autour du stade mature de la plantation de palmiers à huile de 10 ans. Parallèlement, le NDVI augmente et l'albédo diminue à proximité des valeurs typiques des forêts. Le bilan énergétique de surface et le partitionnement énergétique montrent des tendances de développement liés aux variables biophysiques et à l'âge des plantations de palmiers à huile. Les nouvelles plantations et les jeunes plantations (&lt;5 ans) ont un rayonnement net plus faible que les plantations de palmiers à huile matures, mais ont des températures de surface plus élevées que les plantations de palmiers à huile matures. (Suite et fin du résumé dans la thèse)<br>Over the last decades, Indonesia has experienced dramatic land transformations with an expansion of oil palm plantations at the expense of tropical forests. Indonesia is currently one of the regions with the highest transformation rate of the land surface worldwide related to the expansion of oil palm plantations and other cash crops replacing forests on large scales. As vegetation is a modifier of the climate near the ground these large-scale land transformations have major impacts on surface biophysical variables such as land surface temperature (LST), albedo, vegetation indices (e.g. the normalized difference vegetation index, NDVI), on the surface energy balance and energy partitioning.Despite the large historic land transformation in Indonesia toward oil palm and other cash crops and governmental plans for future expansion, this is the first study so far to quantify the impacts of land transformation on biophysical variables in Indonesia. To assess such changes at regional scale remote sensing data are needed.As a key driver for many ecological functions, LST is directly affected by land cover changes.We analyze LST from the thermal band of a Landsat image and produce a high-resolution surface temperature map (30 m) for the lowlands of the Jambi province in Sumatra (Indonesia), a region which experienced large land transformation towards oil palm and other cash crops over the past decades. The comparison of LST, albedo, NDVI, and evapotranspiration (ET) between seven different land cover types (forest, urban areas, clear cut land, young and mature oil palm plantations, acacia and rubber plantations) shows that forests have lower surface temperatures than the other land cover types, indicating a local warming effect after forest conversion. LST differences were up to 10.1 ± 2.6 ºC (mean ± SD) between forest and clear-cut land. The differences in surface temperatures are explained by an evaporative cooling effect, which offsets an albedo warming effect.Young and mature oil palm plantations differenced in their biophysical. To study the development of surface biophysical variables during the 20 – 25 years rotation cycle of oil palm plantations, we used three Landsat images from the Jambi province in Sumatra/Indonesia covering a chronosequence of oil palm plantations.Our results show that differences between oil palm plantations in different stages of the oil palm rotation cycle are reflected in differences in the surface energy balance, energy partitioning and biophysical variables. During the oil palm plantation lifecycle the surface temperature differences to forest gradually decrease and approach zero around the mature oil palm plantation stage of 10 years. Concurrently, NDVI increases and the albedo decreases approaching typical values of forests. The surface energy balance and energy partitioning show a development patterns related to biophysical variables and the age of the oil palm plantations. Newly established and young plantations (&lt; 5 years) have less net radiation available than mature oil palm plantations, yet have higher surface temperatures than mature oil palm plantations. The changes in biophysical variables, energy balance and energy partitioning during the oil palm rotation cycle can be explained by the previously identified evaporative cooling effect in which the albedo warming effect is offset. A main determinant in this mechanism is the vegetation cover during the different phases in the oil palm rotation cycle. NDVI as a proxy for vegetation cover showed a consistent inverse relation with the LST of different aged oil palm plantations, a trend that is also observed for different land use types in this study. (Last and final summary in the thesis)
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48

Ellsäßer, Florian. "Predicting evapotranspiration from drone-recorded land surface temperatures - Method testing and development." Doctoral thesis, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-147C-A.

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49

Smith, Rebecca. "Mid-Pliocene to Early Pleistocene Sea Surface and Land Temperature History of NW Australia Based on Organic Geochemical Proxies from Site U1463." 2018. https://scholarworks.umass.edu/masters_theses_2/722.

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Ocean gateways facilitate water circulation between ocean basins, and therefore directly impact thermohaline circulation and global climate. In order to better predict the effects of future climate change, it is critical to constrain past changes in ocean gateway behavior, and corresponding changes in thermohaline circulation, particularly during analogue periods for modern climate change. The Indonesian Throughflow (ITF) is a primary ocean gateway and vital component of the global conveyor that transports water from the Pacific Ocean into the Indian Ocean, however due to a lack of long and continuous sedimentary records from locations under its influence, changes in ITF behavior remain poorly constrained. In this study organic geochemical biomarkers preserved in marine sediments are used to reconstruct both sea surface and continental air temperatures in Northwest (NW) Australia from sediments spanning the mid-Pliocene Warm Period (mPWP), a critical carbon dioxide (CO2) and temperature analogue period for modern climate change spanning 3.3-3.0 Ma. These sediments were collected during IODP Expedition 356 from Site U1463, located near the outlet of the ITF, and are therefore sensitive to changes in ITF behavior over time. Here, NW Australian air temperatures were reconstructed from 1.5-3.5 Ma using the MBT’5ME proxy (Weijers et al., 2007a; De Jonge et al., 2014a), and offshore sea surface temperatures (SSTs) were reconstructed using both the TEX86 proxy (Schouten et al., 2002; Tierney & Tingley, 2014) and the Long Chain Diol Index (LDI; Rampen et al., 2012). Global climate events, including Marine Isotope Stages (MIS) 55, 63, 64, 82, 84, 88, 92, G10, G18, G20, G22, and M2 (Lisiecki & Raymo, 2005) are apparent in all of our records. TEX86 SSTs suggest a stronger cooling signal during MIS Stages G18, G20 and G22 relative to cooling during MIS M2, however LDI SSTs do not yield the same result. Overall, all three proxies indicate higher temperatures across the Pliocene and a cooling trend from ~1.7-1.5 Ma. Cooling occurs during an arid interval identified by Christensen et al. (2017), from 2.4-1.0 Ma, which suggests that offshore cooling contributed to shifts in NW Australian continental hydrology. Cooling from 3.5-1.5 Ma at Site U1463 was likely a reflection of 1) constriction of the ITF from 5-2 Ma and a switch from warm South Pacific to cool North Pacific source waters, and 2) an increase in meridional SST gradients at 1.8 Ma; the particularly strong cooling signal identified in all three records at 1.7 Ma is likely a direct response to the latter. This study helps elucidate ITF variability and shifts in thermohaline circulation across the Plio-Pleistocene and the mPWP, which will help modelers better predict the effects of future climate change.
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50

Phan, Thanh Noi. "Air Surface Temperature Estimation Using MODIS Land Surface Temperature Data in Northwest Vietnam." Thesis, 2018. http://hdl.handle.net/21.11130/00-1735-0000-0003-C17B-9.

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