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Статті в журналах з теми "Oxygen isotopes, atmospheric effects"

Автор: Grafiati

Опубліковано: 15 вересня 2021

Оновлено: 30 липня 2025

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1

Passey, Benjamin H. "Reconstructing Terrestrial Environments Using Stable Isotopes in Fossil Teeth and Paleosol Carbonates." Paleontological Society Papers 18 (November 2012): 167–94. http://dx.doi.org/10.1017/s1089332600002606.

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Carbon isotopes in Neogene-age fossil teeth and paleosol carbonates are commonly interpreted in the context of past distributions of C3 and C4 vegetation. These two plant types have very different distributions in relation to climate and ecology, and provide a robust basis for reconstructing terrestrial paleoclimates and paleoenvironments during the Neogene. Carbon isotopes in pre-Neogene fossil teeth are usually interpreted in the context of changes in the δ13C value of atmospheric CO2, and variable climate-dependent carbon-isotope discrimination in C3 plants. Carbon isotopes in pre-Neogene s

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2

Extier, Thomas, Thibaut Caley, and Didier M. Roche. "Modelling water isotopologues (¹H²H¹⁶O, ¹H₂¹⁷O) in the coupled numerical climate model iLOVECLIM (version 1.1.5)." Geoscientific Model Development 17, no. 5 (2024): 2117–39. http://dx.doi.org/10.5194/gmd-17-2117-2024.

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Abstract. Stable water isotopes are used to infer changes in the hydrological cycle for different climate periods and various climatic archives. Following previous developments of δ18O in the coupled climate model of intermediate complexity, iLOVECLIM, we present here the implementation of the 1H2H16O and 1H217O water isotopes in the different components of this model and calculate the associated secondary markers deuterium excess (d-excess) and oxygen-17 excess (17O-excess) in the atmosphere and ocean. So far, the latter has only been modelled by the atmospheric model LMDZ4. Results of a 5000

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3

Michalski, G., S. K. Bhattacharya, and G. Girsch. "NO<sub>x</sub> cycle and the tropospheric ozone isotope anomaly: an experimental investigation." Atmospheric Chemistry and Physics 14, no. 10 (2014): 4935–53. http://dx.doi.org/10.5194/acp-14-4935-2014.

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Abstract. The oxygen isotope composition of nitrogen oxides (NOx) in the atmosphere is a useful tool for understanding the oxidation of NOx into nitric acid / nitrate in the atmosphere. A set of experiments was conducted to examine change in isotopic composition of NOx due to NOx–O2–O3 photochemical cycling. At low NOx / O2 mixing ratios, NOx became progressively and nearly equally enriched in 17O and 18O over time until it reached a steady state with Δ17O values of 39.3 ± 1.9‰ and δ18O values of 84.2 ± 4‰, relative to the isotopic composition of the initial O2 gas. As the mixing ratios were i

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4

Gao, Jing, You He, Valerie Masson-Delmotte, and Tandong Yao. "ENSO Effects on Annual Variations of Summer Precipitation Stable Isotopes in Lhasa, Southern Tibetan Plateau." Journal of Climate 31, no. 3 (2018): 1173–82. http://dx.doi.org/10.1175/jcli-d-16-0868.1.

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Abstract Although El Niño–Southern Oscillation (ENSO) influences the Indian summer monsoon, its impact on moisture transport toward the southern Tibetan Plateau (TP) remains poorly understood. Precipitation stable isotopes are useful indices for climate change in the TP. Classical interpretations of variations of precipitation stable isotopes focus on the local surface air temperature or precipitation amount. However, several of the latest studies suggested they may correlate with large-scale modes of variability, such as ENSO. This paper presents a detailed study of ENSO’s effect on annual va

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5

Nyamgerel, Yalalt, Yeongcheol Han, Minji Kim, Dongchan Koh, and Jeonghoon Lee. "Review on Applications of 17O in Hydrological Cycle." Molecules 26, no. 15 (2021): 4468. http://dx.doi.org/10.3390/molecules26154468.

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The triple oxygen isotopes (16O, 17O, and 18O) are very useful in hydrological and climatological studies because of their sensitivity to environmental conditions. This review presents an overview of the published literature on the potential applications of 17O in hydrological studies. Dual-inlet isotope ratio mass spectrometry and laser absorption spectroscopy have been used to measure 17O, which provides information on atmospheric conditions at the moisture source and isotopic fractionations during transport and deposition processes. The variations of δ17O from the developed global meteoric

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6

Jiang, Zhuang, Joel Savarino, Becky Alexander, Joseph Erbland, Jean-Luc Jaffrezo, and Lei Geng. "Impacts of post-depositional processing on nitrate isotopes in the snow and the overlying atmosphere at Summit, Greenland." Cryosphere 16, no. 7 (2022): 2709–24. http://dx.doi.org/10.5194/tc-16-2709-2022.

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Abstract. The effect of post-depositional processing on the preservation of snow nitrate isotopes at Summit, Greenland, remains a subject of debate and is relevant to the quantitative interpretation of ice-core nitrate (isotopic) records at high snow accumulation sites. Here we present the first year-round observations of atmospheric nitrate and its isotopic compositions at Summit and compare them with published surface snow and snowpack observations. The atmospheric δ15N(NO3-) remained negative throughout the year, ranging from −3.1 ‰ to −47.9 ‰ with a mean of (−14.8 ± 7.3) ‰ (n=54), and disp

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7

Schumacher, M., R. E. M. Neubert, H. A. J. Meijer, et al. "Oxygen isotopic signature of CO<sub>2</sub> from combustion processes." Atmospheric Chemistry and Physics Discussions 8, no. 6 (2008): 18993–9034. http://dx.doi.org/10.5194/acpd-8-18993-2008.

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Abstract. For a comprehensive understanding of the global carbon cycle precise knowledge of all processes is necessary. Stable isotope (13C and 18O) abundances provide information for the qualification and the quantification of the diverse source and sink processes. This study focuses on the δ18O signature of CO2 from combustion processes, which are widely present both naturally (wild fires), and human induced (fossil fuel combustion, biomass burning) in the carbon cycle. All these combustion processes use atmospheric oxygen, of which the isotopic signature is assumed to be constant with time

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8

NOON, PHILIPPA E., M. J. LENG, C. ARROWSMITH, M. G. EDWORTHY, and R. J. STRACHAN. "Seasonal observations of stable isotope variations in a valley catchment, Signy Island, South Orkney Islands." Antarctic Science 14, no. 4 (2002): 333–42. http://dx.doi.org/10.1017/s0954102002000159.

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The oxygen and hydrogen isotope composition of waters in a small valley at Signy Island, South Orkney Islands, were monitored over three summers (1999 to 2001). These stable isotopes track water movement through the catchment, especially seasonal precipitation and snow melt. All samples fall close to the regional meteoric water line but factors other than air temperature cause year-to-year variability. Residence times are in the order of days thus the lake water provides an average of precipitation falling only a few days before, except in the winter when the lakes are effectively closed. Free

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9

Schumacher, M., R. A. Werner, H. A. J. Meijer, et al. "Oxygen isotopic signature of CO<sub>2</sub> from combustion processes." Atmospheric Chemistry and Physics 11, no. 4 (2011): 1473–90. http://dx.doi.org/10.5194/acp-11-1473-2011.

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Abstract. For a comprehensive understanding of the global carbon cycle precise knowledge of all processes is necessary. Stable isotope (13C and 18O) abundances provide information for the qualification and the quantification of the diverse source and sink processes. This study focuses on the δ18O signature of CO2 from combustion processes, which are widely present both naturally (wild fires), and human induced (fossil fuel combustion, biomass burning) in the carbon cycle. All these combustion processes use atmospheric oxygen, of which the isotopic signature is assumed to be constant with time

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10

Zahn, A., P. Franz, C. Bechtel, J. U. Grooß, and T. Röckmann. "Modelling the budget of middle atmospheric water vapour isotopes." Atmospheric Chemistry and Physics 6, no. 8 (2006): 2073–90. http://dx.doi.org/10.5194/acp-6-2073-2006.

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Abstract. A one-dimensional chemistry model is applied to study the stable hydrogen (D) and stable oxygen isotope (17O, 18O) composition of water vapour in stratosphere and mesosphere. In the troposphere, this isotope composition is determined by "physical'' fractionation effects, that are phase changes (e.g. during cloud formation), diffusion processes (e.g. during evaporation from the ocean), and mixing of air masses. Due to these processes water vapour entering the stratosphere first shows isotope depletions in D/H relative to ocean water, which are ~5 times of those in 18O/16O, and secondl

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11

Bai, Wenwen, Jiahua Wei, Yang Shi, Zhifeng Zhao, and Qiong Li. "Microphysical Characteristics and Environmental Isotope Effects of the Micro-Droplet Groups under the Action of Acoustic Waves." Atmosphere 12, no. 11 (2021): 1488. http://dx.doi.org/10.3390/atmos12111488.

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Acoustics can cause particles/droplets to agglomerate in the air medium, thereby accelerating gravity sedimentation. To assess the microphysical characteristics and environmental isotope effects of micro-droplet groups under the action of acoustic waves, an air chamber experimental platform was established, and 100 groups of controlled experiments were conducted. The characteristic particle size, size spectrum, isotope values, corresponding linear relationships with hydrogen and oxygen, and d values were analyzed. The isotope exchange equation between the micro-droplet groups and environmental

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12

Liang, Mao-Chang, Yi-Chun Chen, Yi-Qin Gao, Xi Zhang, and Yuk L. Yung. "Atmospheric Effects on the Isotopic Composition of Ozone." Atmosphere 12, no. 12 (2021): 1673. http://dx.doi.org/10.3390/atmos12121673.

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The delta values of the isotope composition of atmospheric ozone is ~100‰ (referenced to atmospheric O2). Previous photochemical models, which considered the isotope fractionation processes from both formation and photolysis of ozone, predicted δ49O3 and δ50O3 values, in δ49O3 versus δ50O3 space, that are >10‰ larger than the measurements. We propose that the difference between the model and observations could be explained either by the temperature variation, Chappuis band photolysis, or a combination of the two and examine them. The isotopic fractionation associated with ozone formation in

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13

Bauch, Henning A., Helmut Erlenkeuser, Pieter M. Grootes, and Jean Jouzel. "Implications of Stratigraphic and Paleoclimatic Records of the Last Interglaciation from the Nordic Seas." Quaternary Research 46, no. 3 (1996): 260–69. http://dx.doi.org/10.1006/qres.1996.0065.

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Climatic reconstruction of glacial to interglacial episodes from oxygen isotopes in sediment cores from the Nordic seas is complicated by strong local meltwater contributions to the oxygen isotope changes. Combination of benthic and planktic foraminiferal isotope data with foraminiferal abundances and ice-rafted debris (IRD) allows separation of local and global effects and subdivision of the marine oxygen isotope events 6.2–5.4, which include the last interglaciation, into: (1) a meltwater phase after glacial stage 6, recorded by large amounts of IRD and low foraminiferal abundance, indicatin

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14

Zhou, Zhihua, and Jun Zhong. "Role of Atmospheric Temperature and Seismic Activity in Spring Water Hydrogeochemistry in Urumqi, China." International Journal of Environmental Research and Public Health 19, no. 19 (2022): 12004. http://dx.doi.org/10.3390/ijerph191912004.

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Springs offer insight into the sources and mechanisms of groundwater recharge and can be used to characterize fluid migration during earthquakes. However, few reports provide sufficient annual hydrochemical and isotopic data to compare the variation characteristics and mechanisms with both atmospheric temperature and seismic effects. In this study, we used continuous δ2H, δ18O, and major ion data from four springs over 1 year to understand the groundwater origin, recharge sources, circulation characteristics, and coupling relationships with atmospheric temperature and earthquakes. We found tha

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15

Lin, Mang, Xiaolin Zhang, Menghan Li, et al. "Five-S-isotope evidence of two distinct mass-independent sulfur isotope effects and implications for the modern and Archean atmospheres." Proceedings of the National Academy of Sciences 115, no. 34 (2018): 8541–46. http://dx.doi.org/10.1073/pnas.1803420115.

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The signature of mass-independent fractionation of quadruple sulfur stable isotopes (S-MIF) in Archean rocks, ice cores, and Martian meteorites provides a unique probe of the oxygen and sulfur cycles in the terrestrial and Martian paleoatmospheres. Its mechanistic origin, however, contains some uncertainties. Even for the modern atmosphere, the primary mechanism responsible for the S-MIF observed in nearly all tropospheric sulfates has not been identified. Here we present high-sensitivity measurements of a fifth sulfur isotope, stratospherically produced radiosulfur, along with all four stable

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16

Zhang, Ao, Xinwen Zhao, Jun He, Xuan Huang, Xingyuezi Zhao, and Yongbo Zhao. "Characteristics of Hydrogen and Oxygen Isotope Composition in Precipitation, Rivers, and Lakes in Wuhan and the Ecological Environmental Effects of Lakes." Water 15, no. 16 (2023): 2996. http://dx.doi.org/10.3390/w15162996.

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Wuhan has a dense network of rivers and lakes. Due to the city’s development, the water system has been fragmented, the degradation of lakes is becoming increasingly severe, and the eco-environment has been significantly damaged. By collecting samples of the central surface water bodies in Wuhan, including Yangtze River water, Han River water, lake water, and precipitation, and by utilizing hydrogen and oxygen isotopes and multivariate statistical methods, the hydraulic connectivity and ecological environmental effects between the Yangtze River, the Han River, and the lakes were revealed. The

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17

Savarino, J., J. Kaiser, S. Morin, D. M. Sigman, and M. H. Thiemens. "Nitrogen and oxygen isotopic constraints on the origin of atmospheric nitrate in coastal Antarctica." Atmospheric Chemistry and Physics 7, no. 8 (2007): 1925–45. http://dx.doi.org/10.5194/acp-7-1925-2007.

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Abstract. Throughout the year 2001, aerosol samples were collected continuously for 10 to 15 days at the French Antarctic Station Dumont d'Urville (DDU) (66°40' S, l40°0' E, 40 m above mean sea level). The nitrogen and oxygen isotopic ratios of particulate nitrate at DDU exhibit seasonal variations that are among the most extreme observed for nitrate on Earth. In association with concentration measurements, the isotope ratios delineate four distinct periods, broadly consistent with previous studies on Antarctic coastal areas. During austral autumn and early winter (March to mid-July), nitrate

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18

He, Yuanqing, Hongxi Pang, W. H. Theakstone, et al. "Spatial and temporal variations of oxygen isotopes in snowpacks and glacial runoff in different types of glacial area in western China." Annals of Glaciology 43 (2006): 269–74. http://dx.doi.org/10.3189/172756406781811943.

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AbstractIn order to improve understanding of spatial and temporal variations of stable isotopes in atmospheric precipitation, snow cover and glacier meltwater in different regions of China, samples were collected for isotopic analysis in four areas: Yulong mountain, Yunnan Himalaya (temperate-glacier area); Samdain Kangsang mountain, Nyainqêntanglha Shan (subpolar-glacier area); the headwater area of the Ürümqi river, Tien Shan (subpolar-glacier area); and Muztag mountain, Pamirs (polar-glacier area). Sampling was undertaken in both summer and winter between 2000 and 2003. The δ18O values show

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19

Caley, T., та D. M. Roche. "δ<sup>18</sup>O water isotope in the <i>i</i>LOVECLIM model (version 1.0) – Part 3: A palaeo-perspective based on present-day data–model comparison for oxygen stable isotopes in carbonates". Geoscientific Model Development 6, № 5 (2013): 1505–16. http://dx.doi.org/10.5194/gmd-6-1505-2013.

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Abstract. Oxygen stable isotopes (δ18O) are among the most useful tools in palaeoclimatology/palaeoceanography. Simulation of oxygen stable isotopes allows testing how the past variability of these isotopes in water can be interpreted. By modelling the proxy directly in the model, the results can also be directly compared with the data. Water isotopes have been implemented in the global three-dimensional model of intermediate complexity iLOVECLIM, allowing fully coupled atmosphere–ocean simulations. In this study, we present the validation of the model results for present-day climate against t

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20

Hermoso, M., I. Z. X. Chan, H. L. O. McClelland, A. M. C. Heureux, and R. E. M. Rickaby. "Vanishing coccolith vital effects with alleviated carbon limitation." Biogeosciences 13, no. 1 (2016): 301–12. http://dx.doi.org/10.5194/bg-13-301-2016.

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Abstract. By recreating a range of geologically relevant concentrations of dissolved inorganic carbon (DIC) in the laboratory, we demonstrate that the magnitude of the vital effects in both carbon and oxygen isotopes of coccolith calcite of multiple species relates to ambient DIC concentration. Under high DIC levels, all the examined coccoliths exhibit significantly reduced isotopic offsets from inorganic calcite compared to the substantial vital effects expressed at low (preindustrial and present-day) DIC concentrations. The supply of carbon to the cell exerts a primary control on biological

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21

Hu, Huancui, Francina Dominguez, Praveen Kumar, Jeffery McDonnell, and David Gochis. "A Numerical Water Tracer Model for Understanding Event-Scale Hydrometeorological Phenomena." Journal of Hydrometeorology 19, no. 6 (2018): 947–67. http://dx.doi.org/10.1175/jhm-d-17-0202.1.

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Abstract We develop and implement a novel numerical water tracer model within the Noah LSM with multiparameterization options (WT-Noah-MP) that is specifically designed to track individual hydrometeorological events. This approach provides a more complete representation of the physical processes beyond the standard land surface model output. Unlike isotope-enabled LSMs, WT-Noah-MP does not simulate the concentration of oxygen or hydrogen isotopes, or require isotope information to drive it. WT-Noah-MP provides stores, fluxes, and transit time estimates of tagged water in the surface–subsurface

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22

Hermoso, M., I. Z. X. Chan, H. L. O. McClelland, A. M. C. Heureux, and R. E. M. Rickaby. "Vanishing coccolith vital effects with alleviated CO<sub>2</sub> limitation." Biogeosciences Discussions 12, no. 18 (2015): 15835–66. http://dx.doi.org/10.5194/bgd-12-15835-2015.

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Abstract. By recreating a range of geologically relevant concentrations of dissolved inorganic carbon (DIC) in the laboratory, we demonstrate that the magnitude of the vital effects in both carbon and oxygen isotopes of coccolith calcite of multiple species relates to ambient DIC concentration. Under high DIC levels, all the examined coccoliths lacked any offset from inorganic calcite, whereas in low (present-day) DIC concentrations, these vital effects and interspecies differences become substantial. These laboratory observations support the recent hypothesis from field observations that the

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23

Albertin, Sarah, Joël Savarino, Slimane Bekki, et al. "Diurnal variations in oxygen and nitrogen isotopes of atmospheric nitrogen dioxide and nitrate: implications for tracing NO_x oxidation pathways and emission sources." Atmospheric Chemistry and Physics 24, no. 2 (2024): 1361–88. http://dx.doi.org/10.5194/acp-24-1361-2024.

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Abstract. The oxygen (Δ17O) and nitrogen (δ15N) isotopic compositions of atmospheric nitrate (NO3-) are widely used as tracers of its formation pathways, precursor (nitrogen oxides (NOx) ≡ nitric oxide (NO) + nitrogen dioxide (NO2)) emission sources, and physico-chemical processing. However, the lack of observations on the multi-isotopic composition of NO2 perpetuates significant uncertainties regarding the quantitative links between the isotopic composition of NOx and NO3-, which ultimately may bias inferences about NO3- formation processes and the distribution of sources, particularly in win

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24

Tsunogai, U., D. D. Komatsu, T. Ohyama, et al. "Quantifying the effects of clear-cutting and strip-cutting on nitrate dynamics in a forested watershed using triple oxygen isotopes as tracers." Biogeosciences 11, no. 19 (2014): 5411–24. http://dx.doi.org/10.5194/bg-11-5411-2014.

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Abstract. Temporal variations in the stable isotopic compositions of nitrate dissolved in stream water eluted from a cool–temperate forested watershed (8 ha) were measured to quantify the biogeochemical effects of clear-cutting of trees and subsequent strip-cutting of the understory vegetation, dwarf bamboo (Sasa senanensis), with special emphasis on changes in the fate of atmospheric nitrate that had been deposited onto the watershed based on Δ17O values of nitrate. A significant increase in stream nitrate concentration to 15 μmol L−1 in spring of 2004 was correlated with a significant increa

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25

Tsunogai, U., D. D. Komatsu, T. Ohyama, et al. "Quantifying the effects of clear-cutting and strip-cutting on nitrate dynamics in a forested watershed using triple oxygen isotopes as tracers." Biogeosciences Discussions 11, no. 5 (2014): 7413–50. http://dx.doi.org/10.5194/bgd-11-7413-2014.

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Abstract. Temporal variations in the stable isotopic compositions of nitrate dissolved in stream water eluted from a cool-temperate forested watershed (8 ha) were measured to quantify the biogeochemical effects of clear-cutting of trees and subsequent strip-cutting of the understory vegetation, dwarf bamboo (Sasa senanensis), with special emphasis on changes in the fate of atmospheric nitrate that had been deposited onto the watershed based on Δ17O values of nitrate. A significant increase in stream nitrate concentration to 15 μmol L−1 in spring of 2004 was correlated with a significant increa

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26

Farquhar, Graham D., Jon Lloyd, John A. Taylor, et al. "Vegetation effects on the isotope composition of oxygen in atmospheric CO2." Nature 363, no. 6428 (1993): 439–43. http://dx.doi.org/10.1038/363439a0.

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27

Schmidt, J. A., M. S. Johnson, and R. Schinke. "Isotope effects in N<sub>2</sub>O photolysis from first principles." Atmospheric Chemistry and Physics 11, no. 17 (2011): 8965–75. http://dx.doi.org/10.5194/acp-11-8965-2011.

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Abstract. For the first time, accurate first principles potential energy surfaces allow N2O cross sections and isotopic fractionation spectra to be derived that are in agreement with all available experimental data, extending our knowledge to a much broader range of conditions. Absorption spectra of rare N- and O-isotopologues (15N14N16O, 14N15N16O, 15N216O, 14N217O and 14N218O) calculated using wavepacket propagation are compared to the most abundant isotopologue (14N216O). The fractionation constants as a function of wavelength and temperature are in excellent agreement with experimental dat

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28

Boateng, Daniel, Sebastian G. Mutz, Armelle Ballian, et al. "The effects of diachronous surface uplift of the European Alps on regional climate and the oxygen isotopic composition of precipitation." Earth System Dynamics 14, no. 6 (2023): 1183–210. http://dx.doi.org/10.5194/esd-14-1183-2023.

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Abstract. This study presents the simulated response of regional climate and the oxygen isotopic composition of precipitation (δ18Op) to different along-strike topographic evolution scenarios. These simulations are conducted to determine if the previously hypothesized diachronous surface uplift in the Western and Eastern Alps would produce δ18Op signals in the geologic record that are sufficiently large and distinct to be detected using stable isotope paleoaltimetry. We present a series of topographic sensitivity experiments conducted with the water-isotope-tracking atmospheric general circula

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29

Mathias, Justin M., and Richard B. Thomas. "Global tree intrinsic water use efficiency is enhanced by increased atmospheric CO2 and modulated by climate and plant functional types." Proceedings of the National Academy of Sciences 118, no. 7 (2021): e2014286118. http://dx.doi.org/10.1073/pnas.2014286118.

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We conducted a meta-analysis of carbon and oxygen isotopes from tree ring chronologies representing 34 species across 10 biomes to better understand the environmental drivers and physiological mechanisms leading to historical changes in tree intrinsic water use efficiency (iWUE), or the ratio of net photosynthesis (Anet) to stomatal conductance (gs), over the last century. We show a ∼40% increase in tree iWUE globally since 1901, coinciding with a ∼34% increase in atmospheric CO2 (Ca), although mean iWUE, and the rates of increase, varied across biomes and leaf and wood functional types. While

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30

Bostic, Joel T., David M. Nelson, and Keith N. Eshleman. "Downpour dynamics: outsized impacts of storm events on unprocessed atmospheric nitrate export in an urban watershed." Biogeosciences 20, no. 12 (2023): 2485–98. http://dx.doi.org/10.5194/bg-20-2485-2023.

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Abstract. Water quality impacts of stream water nitrate (NO3-) on downstream ecosystems are largely determined by the load of NO3- from the watershed to surface waters. The largest NO3- loads often occur during storm events, but it is unclear how loads of different NO3- sources change during storm events relative to baseflow or how watershed attributes might affect source export. To assess the role of storm flow and baseflow in NO3- source export and how these roles are modulated by hydrologic effects of land-use practices, we measured nitrogen (δ15N) and oxygen (Δ17O) isotopes of NO3- and oxy

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31

Lindroos, Alf, Lior Regev, Markku Oinonen, Åsa Ringbom, and Jan Heinemeier. "14C Dating of Fire-Damaged Mortars from Medieval Finland." Radiocarbon 54, no. 3-4 (2012): 915–31. http://dx.doi.org/10.1017/s0033822200047561.

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This study focuses on radiocarbon dating of mortars that have withstood city fires and display visible fire damage effects. Some fire-damaged and undamaged original Medieval mortars from the same site have also been tested. The mortars were heated at different temperatures and then analyzed using the same preparation procedures as in 14C dating of mortars to see what kind of changes the heating would introduce to the mineralogy, chemistry, and the carbon and oxygen isotope ratios. We found that decarbonation during heating starts at ∼600 ° and recarbonation starts as soon as the temperature dr

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32

Farquhar, Graham D., Jon Lloyd, John A. Taylor, et al. "Erratum: Vegetation effects on the isotope composition of oxygen in atmospheric C02." Nature 365, no. 6444 (1993): 368. http://dx.doi.org/10.1038/365368b0.

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Kern, Z., B. Kohán, and M. Leuenberger. "Precipitation isoscape of high reliefs: interpolation scheme designed and tested for monthly resolved precipitation oxygen isotope records of an Alpine domain." Atmospheric Chemistry and Physics 14, no. 4 (2014): 1897–907. http://dx.doi.org/10.5194/acp-14-1897-2014.

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Abstract. Stable oxygen isotope composition of atmospheric precipitation (δ18Op) was scrutinized from 39 stations distributed over Switzerland and its border zone. Monthly amount-weighted δ18Op values averaged over the 1995–2000 period showed the expected strong linear altitude dependence (−0.15 to −0.22‰ per 100 m) only during the summer season (May–September). Steeper gradients (~ −0.56 to −0.60‰ per 100 m) were observed for winter months over a low elevation belt, while hardly any altitudinal difference was seen for high elevation stations. This dichotomous pattern could be explained by the

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34

Lim, Saehee, Meehye Lee, Joel Savarino та Paolo Laj. "Oxidation pathways and emission sources of atmospheric particulate nitrate in Seoul: based on <i>δ</i><sup>15</sup>N and Δ<sup>17</sup>O measurements". Atmospheric Chemistry and Physics 22, № 8 (2022): 5099–115. http://dx.doi.org/10.5194/acp-22-5099-2022.

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Abstract. PM2.5 haze pollution driven by secondary inorganic NO3- has been a great concern in East Asia. It is, therefore, imperative to identify its sources and oxidation processes, for which nitrogen and oxygen stable isotopes are powerful tracers. Here, we determined the δ15N (NO3-) and Δ17O (NO3-) of PM2.5 in Seoul during the summer of 2018 and the winter of 2018–2019 and estimated quantitatively the relative contribution of oxidation pathways for particulate NO3- and investigated major NOx emission sources. In the range of PM2.5 mass concentration from 7.5 µg m−3 (summer) to 139.0 µg m−3

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35

Meredith, Michael P., Hugh J. Venables, Andrew Clarke, et al. "The Freshwater System West of the Antarctic Peninsula: Spatial and Temporal Changes." Journal of Climate 26, no. 5 (2013): 1669–84. http://dx.doi.org/10.1175/jcli-d-12-00246.1.

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Abstract Climate change west of the Antarctic Peninsula is the most rapid of anywhere in the Southern Hemisphere, with associated changes in the rates and distributions of freshwater inputs to the ocean. Here, results from the first comprehensive survey of oxygen isotopes in seawater in this region are used to quantify spatial patterns of meteoric water (glacial discharge and precipitation) separately from sea ice melt. High levels of meteoric water are found close to the coast, due to orographic effects on precipitation and strong glacial discharge. Concentrations decrease offshore, driving s

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36

Schmidt, J. A., M. S. Johnson, and R. Schinke. "Isotope effects in N<sub>2</sub>O photolysis from first principles." Atmospheric Chemistry and Physics Discussions 11, no. 5 (2011): 16075–105. http://dx.doi.org/10.5194/acpd-11-16075-2011.

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Abstract. For the first time, accurate potential energy surfaces allow N2O cross sections and isotopic fractionation spectra to be derived that are in agreement with available experimental data (without ad hoc shifting), extending knowledge to a much broader range of conditions. Absorption spectra of rare N- and O-isotopologues (15N14N16O, 14N15N16O, 15N216O, 14N217O and 14N218O) calculated using wavepacket propagation are compared to the most abundant isotopologue (14N216O). The fractionation constants as a function of wavelength and temperature are in excellent agreement with experimental da

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37

Marshall, James D. "Climatic and oceanographic isotopic signals from the carbonate rock record and their preservation." Geological Magazine 129, no. 2 (1992): 143–60. http://dx.doi.org/10.1017/s0016756800008244.

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AbstractStable isotopic data from marine limestones and their constituent fossils and marine cements can provide quantitative evidence for changes in global climate and ocean circulation. Oxygen isotopic data can indicate changes in temperature and ocean composition whereas stratigraphic variation in carbon isotope ratios may reflect changes in the carbon cycle that can be linked to changes in oceanic productivity and atmospheric greenhouse gases. Terrestrial carbonates–meteoric cements, calcretes and speleothems–similarly offer significant potential for understanding the evolution of terrestr

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38

Schlosser, Elisabeth. "Effects of seasonal variability of accumulation on yearly mean δ18O values in Antarctic snow". Journal of Glaciology 45, № 151 (1999): 463–68. http://dx.doi.org/10.3189/s0022143000001325.

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AbstractThe annual mean oxygen-isotope content of Antarctic snow is strongly influenced by the seasonal variability of accumulation. Since the annual mean δ18O value is frequently used to derive mean annual temperatures from ice cores, changes in atmospheric circulation pattern can lead to large errors in the deduced temperature record. At the German Antarctic wintering base, Neumayer, accumulation measurements have been carried out continuously over the last 16 years. Weekly readings of accumulation stakes combined with snow pits and shallow firn cores are used to investigate the influence of

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39

Schlosser, Elisabeth. "Effects of seasonal variability of accumulation on yearly mean δ18O values in Antarctic snow". Journal of Glaciology 45, № 151 (1999): 463–68. http://dx.doi.org/10.1017/s0022143000001325.

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AbstractThe annual mean oxygen-isotope content of Antarctic snow is strongly influenced by the seasonal variability of accumulation. Since the annual mean δ18O value is frequently used to derive mean annual temperatures from ice cores, changes in atmospheric circulation pattern can lead to large errors in the deduced temperature record. At the German Antarctic wintering base, Neumayer, accumulation measurements have been carried out continuously over the last 16 years. Weekly readings of accumulation stakes combined with snow pits and shallow firn cores are used to investigate the influence of

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40

Sokratov, S. A., A. Yu Komarov, Yu K. Vasil’chuk та ін. "Spatial-Temporal Variability of the δ<sup>18</sup>O Values and the Snow Cover Structure on the Territory of the Meteorological Observatory of the Lomonosov Moscow State University". Journal "Ice and snow" 63, № 4 (2023): 569–82. http://dx.doi.org/10.31857/s2076673423040154.

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Received July 3, 2023; revised September 4, 2023; accepted October 2, 2023The isotopic composition (δ18O values) of snow layers, constructing snow cover to the time of reaching maximum snow water equivalent (SWE), was compared with the isotopic content of snow precipitated over the whole the winter season 2018/19 on the territory of the Meteorological Observatory of the Lomonosov Moscow State University (Moscow, Russia). Snow-sampling was carried out in a trench 20 m long simultaneously with detailed measurements of spatial variability of the structural characteristics of snow depth. Sampling

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41

Erbland, J., J. Savarino, S. Morin, J. L. France, M. M. Frey, and M. D. King. "Air–snow transfer of nitrate on the East Antarctic plateau – Part 2: An isotopic model for the interpretation of deep ice-core records." Atmospheric Chemistry and Physics Discussions 15, no. 5 (2015): 6887–966. http://dx.doi.org/10.5194/acpd-15-6887-2015.

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Abstract. Unraveling the modern budget of reactive nitrogen on the Antarctic plateau is critical for the interpretation of ice core records of nitrate. This requires accounting for nitrate recycling processes occurring in near surface snow and the overlying atmospheric boundary layer. Not only concentration measurements, but also isotopic ratios of nitrogen and oxygen in nitrate, provide constraints on the processes at play. However, due to the large number of intertwined chemical and physical phenomena involved, numerical modelling is required to test hypotheses in a~quantitative manner. Here

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42

Sofen, E. D., B. Alexander, and S. A. Kunasek. "The sensitivity of the oxygen isotopes of ice core sulfate to changing oxidant concentrations since the preindustrial." Atmospheric Chemistry and Physics Discussions 10, no. 8 (2010): 20607–23. http://dx.doi.org/10.5194/acpd-10-20607-2010.

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Abstract. Changes in tropospheric oxidant concentrations since preindustrial times have implications for the ozone radiative forcing, lifetimes of reduced trace gases, aerosol formation, and human health but are highly uncertain. Measurements of the triple oxygen isotopes of sulfate in ice cores (described by Δ17OSO4 = δ17O − 0.52 × δ18O) provide one of the few constraints on paleo-oxidants. We use the GEOS-Chem global atmospheric chemical transport model to simulate changes in oxidant concentrations and the Δ17OSO4 between 1850 and 1990 to assess the sensitivity of Δ17OSO4 measurements in Gre

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43

Erbland, J., J. Savarino, S. Morin, J. L. France, M. M. Frey, and M. D. King. "Air–snow transfer of nitrate on the East Antarctic Plateau – Part 2: An isotopic model for the interpretation of deep ice-core records." Atmospheric Chemistry and Physics 15, no. 20 (2015): 12079–113. http://dx.doi.org/10.5194/acp-15-12079-2015.

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Abstract. Unraveling the modern budget of reactive nitrogen on the Antarctic Plateau is critical for the interpretation of ice-core records of nitrate. This requires accounting for nitrate recycling processes occurring in near-surface snow and the overlying atmospheric boundary layer. Not only concentration measurements but also isotopic ratios of nitrogen and oxygen in nitrate provide constraints on the processes at play. However, due to the large number of intertwined chemical and physical phenomena involved, numerical modeling is required to test hypotheses in a quantitative manner. Here we

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44

Pujiindiyati, E. Ristin, Wandowo Wandowo, and Zainal Abidin. "INTERPRETATION OF OXYGEN –18 ISOTOPE IN SULPHATE FROM DEEP GROUNDWATER IN JAKARTA AREA." Indonesian Journal of Chemistry 7, no. 1 (2010): 32–37. http://dx.doi.org/10.22146/ijc.21709.

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It has been done a determination of d 18O (SO42-) and d 18O (H2O) value from Jakarta deep groundwater with depth 40-140 m. The aim of this research is to know some procesess influencing the composition of oxygen isotope in groundwater sulphate. A method commonly used to determine d 18O (H2O) value is according to Epstein-Mayeda. CO2 gas resulted from equilibration process between water sample and CO2 gas standard in which oxygen isotopic reaction has occurred, is injected to mass spectrometer. For determination of d 18O (SO42-) value, Rafter method is used. CO2 gas released from reducing sulph

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45

Lenton, Timothy M., Tais W. Dahl, Stuart J. Daines, et al. "Earliest land plants created modern levels of atmospheric oxygen." Proceedings of the National Academy of Sciences 113, no. 35 (2016): 9704–9. http://dx.doi.org/10.1073/pnas.1604787113.

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The progressive oxygenation of the Earth’s atmosphere was pivotal to the evolution of life, but the puzzle of when and how atmospheric oxygen (O2) first approached modern levels (∼21%) remains unresolved. Redox proxy data indicate the deep oceans were oxygenated during 435–392 Ma, and the appearance of fossil charcoal indicates O2 >15–17% by 420–400 Ma. However, existing models have failed to predict oxygenation at this time. Here we show that the earliest plants, which colonized the land surface from ∼470 Ma onward, were responsible for this mid-Paleozoic oxygenation event, through greatly

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46

Köhler, Inga, Raul E. Martinez, David Piatka, et al. "How are oxygen budgets influenced by dissolved iron and growth of oxygenic phototrophs in an iron-rich spring system? Initial results from the Espan Spring in Fürth, Germany." Biogeosciences 18, no. 15 (2021): 4535–48. http://dx.doi.org/10.5194/bg-18-4535-2021.

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Abstract. At present most knowledge on the impact of iron on 18O / 16O ratios (i.e. δ18O) of dissolved oxygen (DO) under circum-neutral conditions stems from experiments carried out under controlled laboratory conditions. These showed that iron oxidation leads to an increase in δ18ODO values. Here we present the first study on effects of elevated Fe(II) concentrations on the δ18ODO in a natural, iron-rich, circum-neutral watercourse. Our results show that iron oxidation was the major factor for rising dissolved oxygen isotope compositions in the first 85 m of the system in the cold season (Feb

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47

Bechtel, C., and A. Zahn. "The isotope composition of water vapour: A powerful tool to study transport and chemistry of middle atmospheric water vapour." Atmospheric Chemistry and Physics Discussions 3, no. 4 (2003): 3991–4036. http://dx.doi.org/10.5194/acpd-3-3991-2003.

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Abstract. A one-dimensional chemistry model is applied to study the stable hydrogen (D) and stable oxygen isotope (17O, 18O) composition of water vapour in stratosphere and mesosphere. The stable isotope ratios of tropospheric H2O are determined by "physical'' fractionation effects, i.e. phase changes, diffusion processes, and mixing of air masses. Due to these processes water vapour entering the stratosphere (i) is mass-dependently fractionated (MDF), i.e. shifts in the isotope ratio 17O/16O are ~0.52 times of those of 18O/16O and (ii) shows isotope shifts in D/H, which are ~5 times of those

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48

Zuev, Vladimir V., Svetlana L. Bondarenko, and Irina G. Ustinova. "Additive singular spectral model of a dendrochronological signal." Bulletin of the Tomsk Polytechnic University Geo Assets Engineering 334, no. 12 (2023): 56–64. http://dx.doi.org/10.18799/24131830/2023/12/4282.

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Relevance. Allocation of structural components in a dendrochronological signal of annual rings of coniferous trees expands the possibilities of the bioindication method and allows obtaining information about changes in environmental conditions in the past for extended territories. Aim. Creation of an additive singular spectral model based on the frequency trigonometric components of the dendrochronological signal; reconstruction of changes in the total ozone content in the atmosphere in the past, affecting the level of ultraviolet radiation in the B range radiation. Objects. Time series of tot

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49

Sofen, E. D., B. Alexander та S. A. Kunasek. "The impact of anthropogenic emissions on atmospheric sulfate production pathways, oxidants, and ice core Δ<sup>17</sup>O(SO<sub>4</sub><sup>2–</sup>)". Atmospheric Chemistry and Physics 11, № 7 (2011): 3565–78. http://dx.doi.org/10.5194/acp-11-3565-2011.

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Abstract. We use a global three-dimensional chemical transport model to quantify the influence of anthropogenic emissions on atmospheric sulfate production mechanisms and oxidant concentrations constrained by observations of the oxygen isotopic composition (Δ17O = &amp;delta17O–0.52 × &amp;delta18O) of sulfate in Greenland and Antarctic ice cores and aerosols. The oxygen isotopic composition of non-sea salt sulfate (Δ17O(SO42–)) is a function of the relative importance of each oxidant (e.g. O3, OH, H2O2, and O2) during sulfate formation, and can be used to quantify sulfate production p

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50

Lyu, Sidan, та Jing Wang. "Transpiration Induced Changes in Atmospheric Water Vapor δ18O via Isotopic Non-Steady-State Effects on a Subtropical Forest Plantation". Water 14, № 17 (2022): 2648. http://dx.doi.org/10.3390/w14172648.

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Accurate simulation of oxygen isotopic composition (δ18OT) of transpiration (T) and its contribution via isotopic non-steady-state (NSS) to atmospheric water vapor δ18O (δ18Ov) still faces great challenges. High-frequency in-situ measurements of δ18Ov and evapotranspiration (ET) δ18O were conducted for two summer days on a subtropical forest plantation. δ18O of xylem, leaf, and soil water at 3 or 4-h intervals was analyzed. Leaf water δ18O and δ18OT were estimated using the Craig and Gordon (CG), Dongmann and Farquhar–Cernusak models, and evaporation (E) δ18O using the CG model. To quantify th

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