Journal articles: 'Estimateur à noya'

1

Molod, A., H. Salmun, and M. Dempsey. "Estimating Planetary Boundary Layer Heights from NOAA Profiler Network Wind Profiler Data." Journal of Atmospheric and Oceanic Technology 32, no. 9 (September 2015): 1545–61. http://dx.doi.org/10.1175/jtech-d-14-00155.1.

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AbstractAn algorithm was developed to estimate planetary boundary layer (PBL) heights from hourly archived wind profiler data from the NOAA Profiler Network (NPN) sites located throughout the central United States. Unlike previous studies, the present algorithm has been applied to a long record of publicly available wind profiler signal backscatter data. Under clear-sky conditions, summertime averaged hourly time series of PBL heights compare well with Richardson number–based estimates at the few NPN stations with hourly temperature measurements. Comparisons with estimates based on clear-sky reanalysis show that the wind profiler (WP) PBL heights are lower by approximately 250–500 m. The geographical distribution of daily maximum PBL heights corresponds well with the expected distribution based on patterns of surface temperature and soil moisture. Wind profiler PBL heights were also estimated under mostly cloudy-sky conditions, and are generally comparable to the Richardson number–based PBL heights and higher than the reanalysis PBL heights. WP PBL heights have a smaller clear–cloudy condition difference than either of the other two. The algorithm presented here is shown to provide a reliable summertime climatology of daytime hourly PBL heights throughout the central United States.

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Cook, Werner E., and J. Scott Greene. "Gridded Monthly Rainfall Estimates Derived from Historical Atoll Observations." Journal of Atmospheric and Oceanic Technology 36, no. 4 (April 2019): 671–87. http://dx.doi.org/10.1175/jtech-d-18-0140.1.

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AbstractTo provide an analysis tool for areal rainfall estimates, 1° gridded monthly sea level rainfall estimates have been derived from historical atoll rainfall observations contained in the Pacific Rainfall (PACRAIN) database. The PACRAIN database is a searchable repository of in situ rainfall observations initiated and maintained by the University of Oklahoma and supported by a research grant from the National Oceanic and Atmospheric Administration (NOAA)/Climate Program Office/Ocean Observing and Monitoring. The gridding algorithm employs ordinary kriging, a standard geostatistical technique, and selects for nonnegative estimates and for local estimation neighborhoods yielding minimum kriging variance. This methodology facilitates the selection of fixed-size neighborhoods from available stations beyond simply choosing the closest stations, as it accounts for dependence between estimator stations. The number of stations used for estimation is based on bias and standard error exhibited under cross estimation. A cross validation is conducted, comparing estimated and observed rains, as well as theoretical and observed standard errors for the ordinary kriging estimator. The conditional bias of the kriging estimator and the predictive value of kriging standard errors, with respect to observed standard errors, are discussed. Plots of the gridded rainfall estimates are given for sample El Niño and La Niña cases and standardized differences between the estimates produced here and the merged monthly rainfall estimates published by the Global Precipitation Climatology Project (GPCP) are shown and discussed.

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3

Smak, J. "Dwarf Nova Outbursts and Superoutbursts." International Astronomical Union Colloquium 158 (1996): 45–46. http://dx.doi.org/10.1017/s0252921100038185.

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Dwarf nova outbursts provide an almost unique opportunity of getting an insight into the nature of viscosity in accretion disks or, within the α- disk approach, of putting some constraints on α. In particular, the strong dependence of the viscous time-scale on viscosity itself permits us to estimate a almost directly from the observed time-scales. In the case of the hot branch of the ∑ — Te relation, the most reliable estimates (αhot) are based on the rate of decline following the dwarf nova outburst. From a comparison with model light curves calculated with different αs one gets: αhot ≈ 0.2(e.g. Smak 1984b). An independent, but much cruder, estimate can be obtained from the widths of normal outbursts, by assuming that the duration of an outburst represents the travel time of an instability wave across the disk. The result is similar: αhot ≈ 0.2 (Gicger 1987).

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Della Valle, M., and R. Claudi. "The Galactic Nova Rate." International Astronomical Union Colloquium 122 (1990): 53–54. http://dx.doi.org/10.1017/s0252921100068329.

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AbstractThe recently estabilished values of M31 and M33 nova rate, rM31 = 29 ± 4 novae yr−1 (Capaccioli et al.,1989), rM33 = 4 ± 2 novae yr−1 (Della Valle, 1988), seems to be at variance with the present estimates for the galactic nova rate, r = 260 novae yr−1 (Sharov,1972) and r = 73 ± 24 novae yr−1 (Liller and Meyer,1987), if we take into account the luminosity class and the Hubble type of the Galaxy. Assuming the nova production per unit of B–luminosity about constant for spiral galaxies and adopting the derived values of the nova rate of M31, M33 and LMC as calibrators, we estimate a galactic nova rate of rGal = 15 ± 5 novae yr−1.

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5

Smith, Barry D. "Comparison of Productivity Estimates for Laminaria in Nova Scotia." Canadian Journal of Fisheries and Aquatic Sciences 45, no. 3 (March 1, 1988): 557–62. http://dx.doi.org/10.1139/f88-066.

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An estimate of productivity for a southwestern Nova Scotia Laminaria community was obtained using a dynamic simulation model which incorporated data on population recruitment and mortality, lamina growth and attrition, and interspecific competition for L. longicruris and L. digitata. The estimate for the total quantity of particulate material produced by this community at equilibrium is ≈6800 g∙m−2∙yr−1 (wet weight), or ≈408 g C∙m−2∙yr−1. The annual productivity to standing crop ratio (P:S) was determined to be ≈2.1:1. The productivity estimate for this community at equilibrium is considerably lower than a widely cited previous estimate for Laminaria productivity in Nova Scotia, which placed the seaweed zone amongst the most productive plant communities known. An evaluation of the methodology yielding this estimate has indicated that inaccurate estimates of population age structure and mortality have possibly resulted in a significant overestimation of particulate productivity.

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Dobrotka, A., A. Retter, L. Hric, R. Novak, O. Shemmer, and Y. Lipkin. "V1493 AQL an Extremely Distant Nova?" International Astronomical Union Colloquium 194 (2004): 236. http://dx.doi.org/10.1017/s0252921100152819.

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Analysis of CCD photometry performed during 12 nights and the estimate of the distance based on the light curve is presented. The photometric data is modulated with a period of 3.7 h, which we interpret as the orbital period above the period gap distribution of cataclysmic variables. The VSNET light curve combined with data from IAU Circulars suggests a distance of 4.5±0.4 kpc based on t2/t3 time estimates. Two spectra 11 days after the maximum were taken. The expansion velocity of the envelope was derived to be 1658±62 km s–1.

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Munda, Ivka M. "Long-term marine floristic changes around Rovinj (Istrian coast, North Adriatic) estimated on the basis of historical data from Paul Kuckuck’s field diaries from the end of the 19th century." Nova Hedwigia 71, no. 1-2 (September 3, 2000): 1–36. http://dx.doi.org/10.1127/nova/71/2000/1.

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8

O'Brien, Brian D., Murray G. Brown, and George Kephart. "Estimation of Hospital Costs for Colorectal Cancer Care for Nova Scotia." Canadian Journal of Gastroenterology 15, no. 1 (2001): 43–47. http://dx.doi.org/10.1155/2001/975208.

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BACKGROUND: Colorectal cancer (CRC) is the second most common invasive cancer in Canada. Estimates of the costs of care allow estimation of the cost effectiveness of screening for premalignant and early disease.OBJECTIVE: To estimate, from administrative data, the hospital costs incurred by a population-based cohort of CRC cases over three years from diagnosis.DESIGN: All Nova Scotia residents with CRC who were diagnosed in 1990 were identified from the Nova Scotia Cancer Registry. These cases were linked to the administrative files of the Nova Scotia Department of Health, which contain information on diagnosis, procedures and length of stay for all admissions and day surgery visits to Nova Scotia hospitals.MEASUREMENTS: The lengths of stay and hospital-specific per diem rates were used as the measures of resource use. The costs were analyzed in terms of the extent of spread at diagnosis; the time period after diagnosis; the time period before death; and, for typical cases, the age and presence of comorbidity identified during the initial surgical admission.RESULTS: The estimated three-year hospital cost for the complete cohort of 593 cases was $9.8 million. This cost was significantly less for cases with local spread, highest in the six months around, and after diagnosis and in the final six months of life, and highest in the typical cases (patients who were older and had significant comorbid conditions).CONCLUSIONS: Hospital-specific per diem rates and lengths of stay are an approximate measure of hospital resource use.

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9

Rigby, M., R. G. Prinn, S. O'Doherty, S. A. Montzka, A. McCulloch, C. M. Harth, J. Mühle, et al. "Re-evaluation of the lifetimes of the major CFCs and CH3CCl3 using atmospheric trends." Atmospheric Chemistry and Physics Discussions 12, no. 9 (September 18, 2012): 24469–99. http://dx.doi.org/10.5194/acpd-12-24469-2012.

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Abstract. Since the Montreal Protocol on substances that deplete the ozone layer and its amendments came into effect, growth rates of the major ozone depleting substances (ODS), particularly CFC-11, -12 and -113 and CH3CCl3, have declined markedly, paving the way for global stratospheric ozone recovery. Emissions have now fallen to relatively low levels, therefore the rate at which this recovery occurs will depend largely on the atmospheric lifetime of these compounds. The first ODS measurements began in the early 1970s along with the first lifetime estimates calculated by considering their atmospheric trends. We now have global mole fraction records spanning multiple decades, prompting this lifetime re-evaluation. Using surface measurements from the Advanced Global Atmospheric Gases Experiment (AGAGE) and the National Oceanic and Atmospheric Administration Global Monitoring Division (NOAA GMD) from 1978 to 2011, we estimated the lifetime of CFC-11, CFC-12, CFC-113 and CH3CCl3 using a multi-species inverse method. The CFC-11 lifetime of 45 yr, currently recommended in the World Meteorological Organisation (WMO) Scientific Assessment of Ozone Depletion, lies at the lower uncertainty bound of our estimates which are 524066 yr (1-sigma uncertainty) when AGAGE data were used, and 504066 yr when the NOAA network data were used. Our derived lifetime for CFC-113 is higher than the WMO estimates of 85 yr (10488123 using AGAGE, 10387122 using NOAA). Our estimates of the lifetime of CFC-12 and CH3CCl3 agree well with other recent estimates being 10885137 and 10484135 yr (CFC-12, AGAGE and NOAA, respectively) and 5.24.85.6 and 5.24.85.7 yr (CH3CCl3, AGAGE and NOAA, respectively).

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10

Rigby, M., R. G. Prinn, S. O'Doherty, S. A. Montzka, A. McCulloch, C. M. Harth, J. Mühle, et al. "Re-evaluation of the lifetimes of the major CFCs and CH3CCl3 using atmospheric trends." Atmospheric Chemistry and Physics 13, no. 5 (March 6, 2013): 2691–702. http://dx.doi.org/10.5194/acp-13-2691-2013.

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Abstract. Since the Montreal Protocol on Substances that Deplete the Ozone Layer and its amendments came into effect, growth rates of the major ozone depleting substances (ODS), particularly CFC-11, -12 and -113 and CH3CCl3, have declined markedly, paving the way for global stratospheric ozone recovery. Emissions have now fallen to relatively low levels, therefore the rate at which this recovery occurs will depend largely on the atmospheric lifetime of these compounds. The first ODS measurements began in the early 1970s along with the first lifetime estimates calculated by considering their atmospheric trends. We now have global mole fraction records spanning multiple decades, prompting this lifetime re-evaluation. Using surface measurements from the Advanced Global Atmospheric Gases Experiment (AGAGE) and the National Oceanic and Atmospheric Administration Global Monitoring Division (NOAA GMD) from 1978 to 2011, we estimated the lifetime of CFC-11, CFC-12, CFC-113 and CH3CCl3 using a multi-species inverse method. A steady-state lifetime of 45 yr for CFC-11, currently recommended in the most recent World Meteorological Organisation (WMO) Scientific Assessments of Ozone Depletion, lies towards the lower uncertainty bound of our estimates, which are 544861 yr (1-sigma uncertainty) when AGAGE data were used and 524561 yr when the NOAA network data were used. Our derived lifetime for CFC-113 is significantly higher than the WMO estimates of 85 yr, being 10999121 (AGAGE) and 10997124 (NOAA). New estimates of the steady-state lifetimes of CFC-12 and CH3CCl3 are consistent with the current WMO recommendations, being 11195132 and 11295136 yr (CFC-12, AGAGE and NOAA respectively) and 5.044.925.20 and 5.044.875.23 yr (CH3CCl3, AGAGE and NOAA respectively).

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11

Tremblay, M. John, Stephen J. Smith, Brian J. Todd, Pierre M. Clement, and David L. McKeown. "Associations of lobsters (Homarus americanus) off southwestern Nova Scotia with bottom type from images and geophysical maps." ICES Journal of Marine Science 66, no. 9 (June 25, 2009): 2060–67. http://dx.doi.org/10.1093/icesjms/fsp178.

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Abstract Tremblay, M. J., Smith, S. J., Todd, B. J., Clement, P. M., and McKeown, D. L. 2009. Associations of lobsters (Homarus americanus) off southwestern Nova Scotia with bottom type from images and geophysical maps. – ICES Journal of Marine Science, 66: 2060–2067. Images from an underwater towed vehicle (Towcam) were used to estimate densities and to evaluate bottom-type associations of lobsters (Homarus americanus), crabs (Cancer spp.), and scallops (Placopecten magellanicus). Images were obtained in October 2006 along 14 line-transects off southwestern Nova Scotia in an area with productive lobster and scallop fisheries. Lobsters were observed in 4% of the 2044 images, crabs in 7%, and scallops in 40%. On sand, gravel, and cobble seabed, lobsters were readily observable. On rougher substrata with boulders, some lobsters were still evident either in the open or partially hidden in shelters. Estimated densities of lobsters from the images on some transects were 0.04 m−2, approximately half of the estimates of lobster density for adjacent inshore areas from scuba, but 34 times higher than estimates from scallop drags in the same area. Models of animal presence by bottom type were evaluated with categories that were (i) geophysically based (map of bottom type from geophysical characteristics) and (ii) image-based (sediment size from images). Significant relationships were evident with both types of seabed categorization, suggesting that it would be beneficial to stratify surveys using geophysical categories. Depth was also significant in determining presence/absence of lobsters and crabs. There is potential to develop indicators of lobster abundance using underwater imaging, and stratification by bottom type should be incorporated into surveys.

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Bowen, W. D., J. McMillan, and R. Mohn. "Sustained exponential population growth of grey seals at Sable Island, Nova Scotia." ICES Journal of Marine Science 60, no. 6 (January 1, 2003): 1265–74. http://dx.doi.org/10.1016/s1054-3139(03)00147-4.

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Abstract Grey seal pup production on Sable Island, Nova Scotia, has been monitored since the early 1960s. We estimated pup production on Sable Island in 1997 using aerial photography with a correction for detection of pups on the imagery and a statistical model to account for the proportion of pups not born at the time of the survey. A total of 20 863 pups were counted on the colour positives. When corrected for the proportion of pups seen on the imagery (0.96) and the proportion of pups born before the survey (east colony 0.94, west colony 0.66), estimated total pup production was 25 400 with approximate 95% confidence limits of 23 500 and 26 900. The 1997 estimate indicates that pup production in this population, now the largest grey seal colony in the world, has been increasing exponentially at an annual rate of 12.8% for four decades in the face of considerable environmental variability.

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13

Lehr, W., R. Overstreet, R. Jones, L. Eclipse, and D. Simecek-Beatty. "THE NEXT GENERATION IN OIL WEATHERING MODELING." International Oil Spill Conference Proceedings 1997, no. 1 (April 1, 1997): 986–87. http://dx.doi.org/10.7901/2169-3358-1997-1-986.

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ABSTRACT Through a project jointly funded by the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Minerals Management Service (MMS), the Hazardous Material Response and Assessment Division of NOAA (NOAA/HAZMAT) has developed the next generation of the widely used oil weathering model, ADIOS. The algorithms for spreading, emulsification, dispersion, and evaporation have been modified to accommodate new research results. Also, the new version contains a source strength module that estimates leak rates from damaged vessels and new user inputs that allow decisions on the application of standard cleanup strategies such as skimming, burning, and chemical dispersion. Sensitivity analysis is used to identify the relative importance of input parameters and to estimate the reliability of model output results in terms of expected input uncertainty.

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Tamura, Takeshi, Kay I. Ohshima, Hiroyuki Enomoto, Kazutaka Tateyama, Atsuhiro Muto, Shuki Ushio, and Robert A. Massom. "Estimation of thin Sea-ice thickness from NOAA AVHRR data in a polynya off the Wilkes Land coast, East Antarctica." Annals of Glaciology 44 (2006): 269–74. http://dx.doi.org/10.3189/172756406781811745.

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AbstractAntarctic coastal polynyas are major areas of intense ocean–atmosphere heat and moisture flux, and associated high Sea-ice production and dense-water formation. Their accurate detection, including an estimate of thin ice thickness, is therefore very important. In this paper, we apply a technique originally developed in the Arctic to an estimation of Sea-ice thickness using Us National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) data and meteorological data in the Vincennes Bay polynya off Wilkes Land, East Antarctica. The method is based upon the heat-flux calculation using Sea-ice Surface temperature estimates from the Satellite thermal-infrared data combined with global objective analysis (European Centre for Medium-Range Weather Forecasts (ECMWF)) data. The validity of this method is assessed by comparing results with independent ice-surface temperature and ice-thickness data obtained during an Australian-led research cruise to the region in 2003. In thin-ice (polynya) regions, ice thicknesses estimated by the heat-flux calculation using AVHRR and ECMWF data Show reasonable agreement with those estimated by (a) applying the heat-flux calculation to in Situ radiation thermometer and meteorological data and (b) in Situ observations. The Standard deviation of the difference between the AVHRR-derived and in Situ data is ∽0.02 m. Comparison of the AVHRR ice-thickness retrievals with coincident Satellite passive-microwave polarization ratio data confirms the potential of the latter as a means of deriving maps of thin Sea-ice thickness on the wider Scale, uninterrupted by darkness and cloud cover.

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15

Rowe, M. D., and J. A. Perlinger. "Micrometeorological measurement of hexachlorobenzene and polychlorinated biphenyl compound air-water gas exchange in Lake Superior and comparison to model predictions." Atmospheric Chemistry and Physics Discussions 12, no. 1 (January 11, 2012): 983–1017. http://dx.doi.org/10.5194/acpd-12-983-2012.

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Abstract. Air-water exchange fluxes of persistent, bioaccumulative and toxic (PBT) substances are frequently estimated using the Whitman two-film (W2F) method, but micrometeorological flux measurements of these compounds over water are rarely attempted. We measured air-water exchange fluxes of hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs) on 14 July 2006 in Lake Superior using the modified Bowen ratio (MBR) method. Measured fluxes were compared to estimates using the W2F method, and to estimates from an Internal Boundary Layer Transport and Exchange (IBLTE) model that implements the NOAA COARE bulk flux algorithm and gas transfer model. We reveal an inaccuracy in the estimate of water vapor transfer velocity that is commonly used with the W2F method for PBT flux estimation, and demonstrate the effect of use of an improved estimation method. Flux measurements were conducted at three stations with increasing fetch in offshore flow (15, 30, and 60 km) in southeastern Lake Superior. This sampling strategy enabled comparison of measured and predicted flux, as well as modification in near-surface atmospheric concentration with fetch, using the IBLTE model. Fluxes estimated using the W2F model were compared to fluxes measured by MBR. In five of seven cases in which the MBR flux was significantly greater than zero, concentration increased with fetch at 1-m height, which is qualitatively consistent with the measured volatilization flux. As far as we are aware, these are the first reported micrometeorological air-water exchange flux measurements of PCBs.

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Rowe, M. D., and J. A. Perlinger. "Micrometeorological measurement of hexachlorobenzene and polychlorinated biphenyl compound air-water gas exchange in Lake Superior and comparison to model predictions." Atmospheric Chemistry and Physics 12, no. 10 (May 24, 2012): 4607–17. http://dx.doi.org/10.5194/acp-12-4607-2012.

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Abstract. Air-water exchange fluxes of persistent, bioaccumulative and toxic (PBT) substances are frequently estimated using the Whitman two-film (W2F) method, but micrometeorological flux measurements of these compounds over water are rarely attempted. We measured air-water exchange fluxes of hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs) on 14 July 2006 in Lake Superior using the modified Bowen ratio (MBR) method. Measured fluxes were compared to estimates using the W2F method, and to estimates from an Internal Boundary Layer Transport and Exchange (IBLTE) model that implements the NOAA COARE bulk flux algorithm and gas transfer model. We reveal an inaccuracy in the estimate of water vapor transfer velocity that is commonly used with the W2F method for PBT flux estimation, and demonstrate the effect of use of an improved estimation method. Flux measurements were conducted at three stations with increasing fetch in offshore flow (15, 30, and 60 km) in southeastern Lake Superior. This sampling strategy enabled comparison of measured and predicted flux, as well as modification in near-surface atmospheric concentration with fetch, using the IBLTE model. Fluxes estimated using the W2F model were compared to fluxes measured by MBR. In five of seven cases in which the MBR flux was significantly greater than zero, concentration increased with fetch at 1-m height, which is qualitatively consistent with the measured volatilization flux. As far as we are aware, these are the first reported ship-based micrometeorological air-water exchange flux measurements of PCBs.

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17

Zavala, M., S. C. Herndon, R. S. Slott, E. J. Dunlea, L. C. Marr, J. H. Shorter, M. Zahniser, et al. "Characterization of on-road vehicle emissions in the Mexico City Metropolitan Area using a mobile laboratory in chase and fleet average measurement modes during the MCMA-2003 field campaign." Atmospheric Chemistry and Physics 6, no. 12 (November 8, 2006): 5129–42. http://dx.doi.org/10.5194/acp-6-5129-2006.

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Abstract. A mobile laboratory was used to measure on-road vehicle emission ratios during the MCMA-2003 field campaign held during the spring of 2003 in the Mexico City Metropolitan Area (MCMA). The measured emission ratios represent a sample of emissions of in-use vehicles under real world driving conditions for the MCMA. From the relative amounts of NOx and selected VOC's sampled, the results indicate that the technique is capable of differentiating among vehicle categories and fuel type in real world driving conditions. Emission ratios for NOx, NOy, NH3, H2CO, CH3CHO, and other selected volatile organic compounds (VOCs) are presented for chase sampled vehicles in the form of frequency distributions as well as estimates for the fleet averaged emissions. Our measurements of emission ratios for both CNG and gasoline powered "colectivos" (public transportation buses that are intensively used in the MCMA) indicate that – in a mole per mole basis – have significantly larger NOx and aldehydes emissions ratios as compared to other sampled vehicles in the MCMA. Similarly, ratios of selected VOCs and NOy showed a strong dependence on traffic mode. These results are compared with the vehicle emissions inventory for the MCMA, other vehicle emissions measurements in the MCMA, and measurements of on-road emissions in U.S. cities. We estimate NOx emissions as 100 600±29 200 metric tons per year for light duty gasoline vehicles in the MCMA for 2003. According to these results, annual NOx emissions estimated in the emissions inventory for this category are within the range of our estimated NOx annual emissions. Our estimates for motor vehicle emissions of benzene, toluene, formaldehyde, and acetaldehyde in the MCMA indicate these species are present in concentrations higher than previously reported. The high motor vehicle aldehyde emissions may have an impact on the photochemistry of urban areas.

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McMillan, Justine M., Alex E. Hay, Rolf G. Lueck, and Fabian Wolk. "Rates of Dissipation of Turbulent Kinetic Energy in a High Reynolds Number Tidal Channel." Journal of Atmospheric and Oceanic Technology 33, no. 4 (April 2016): 817–37. http://dx.doi.org/10.1175/jtech-d-15-0167.1.

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AbstractThe ability to estimate the rate of dissipation (ε) of turbulent kinetic energy at middepth in a high-speed tidal channel using broadband acoustic Doppler current profilers (ADCPs) is assessed by making comparisons to direct measurements of ε obtained using shear probes mounted on a streamlined underwater buoy. The investigation was carried out in Grand Passage, Nova Scotia, Canada, where the depth-averaged flow speed reached 2 m s−1 and the Reynolds number was 8 × 107. The speed bin–averaged dissipation rates estimated from the ADCP data agree with the shear probe data to within a factor of 2. Both the ADCP and the shear probe measurements indicate a linear dependence of ε on the cube of the flow speed during flood and much lower dissipation rates during ebb. The ebb–flood asymmetry and the small-scale intermittency in ε are also apparent in the lognormal distributions of the shear probe data. Possible sources of bias and error in the ε estimates are investigated, and the most likely causes of the discrepancy between the ADCP and shear probe estimates are the cross-channel separation of the instruments and the high degree of spatial variability that exists in the channel.

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Pons, O. "Vitesse de convergence des estimateurs a noyau pour l'intensite d'un processus ponctuel." Statistics 17, no. 4 (January 1986): 577–84. http://dx.doi.org/10.1080/02331888608801977.

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20

Citadin, Idemir, Sérgio Miguel Mazaro, Moeses Andrigo Danner, Maria do Carmo Bassols Raseira, and Gustavo Malagi. "Variability in leaf rust susceptibility among peach cultivars." Revista Ceres 57, no. 2 (April 2010): 185–93. http://dx.doi.org/10.1590/s0034-737x2010000200008.

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The aim of this work was to estimate the susceptibility of thirty-six peach cultivars to leaf rust caused by Tranzschelia discolor f. sp. persica. The incidence and severity of the disease as well as defoliation in peach trees of an experimental orchard of Parana Federal University of Technology, Campus Dois Vizinhos were evaluated on the growing seasons 2004/2005 and 2005/2006. Immunity to this disease was not observed in the studied cultivars. There was difference in leaf rust intensity depending on the growing season conditions. Cultivars 'Pilcha', 'Sinuelo', 'Chirua', 'Sulina', 'Eldorado' and 'Pampeano' showed tolerance to leaf rust, whereas cultivars 'Vila Nova', 'Fla 1372', 'Coral 2', 'Chimarrita', 'Della Nona', 'BR-1 ' and 'Guaiaca' showed high susceptibility.

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Tippett, Michael K., Timothy DelSole, and Anthony G. Barnston. "Reliability of Regression-Corrected Climate Forecasts." Journal of Climate 27, no. 9 (April 23, 2014): 3393–404. http://dx.doi.org/10.1175/jcli-d-13-00565.1.

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Abstract Regression is often used to calibrate climate model forecasts with observations. Reliability is an aspect of forecast quality that refers to the degree of correspondence between forecast probabilities and observed frequencies of occurrence. While regression-corrected climate forecasts are reliable in principle, the estimated regression parameters used in practice are affected by sampling error. The low skill and small sample sizes typically encountered in climate prediction imply substantial sampling error in the estimated regression parameters. Here the reliability of regression-corrected climate forecasts is analyzed for the case of joint-Gaussian distributed ensemble forecasts and observations with regression parameters estimated by least squares. Hypothesis testing of the regression parameters provides direct information about the skill and reliability of the uncorrected ensemble-based probability forecasts. However, the regression-corrected probability forecasts with estimated parameters are systematically “overconfident” because sampling error causes a positive bias in the regression forecast signal variance, despite the fact that the estimates of the regression parameters are themselves unbiased. An analytical description of the reliability diagram of a generic regression-corrected climate forecast is derived and is shown to depend on sample size and population correlation skill, with small sample size and low skill being factors that increase overconfidence. The analytical reliability estimate is shown to capture the effect of sampling error in synthetic data experiments and in a 29-yr dataset of NOAA Climate Forecast System version 2 predictions of seasonal precipitation totals over the Americas. The impact of sampling error on the reliability of regression-corrected forecast has been previously unrecognized and affects all regression-based forecasts. The use of regression parameters estimated by shrinkage methods such as ridge regression substantially reduces overconfidence.

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Singh, D., I. Herlin, J. P. Berroir, and S. Bouzidi. "An approach to estimate the evapotranspiration using NOAA/AVHRR DATA." Journal of the Indian Society of Remote Sensing 33, no. 2 (June 2005): 211–17. http://dx.doi.org/10.1007/bf02990037.

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23

Harding, Gareth C., and Ronald W. Trites. "Dispersal of Homarus americanus Larvae in the Gulf of Maine from Browns Bank." Canadian Journal of Fisheries and Aquatic Sciences 45, no. 3 (March 1, 1988): 416–25. http://dx.doi.org/10.1139/f88-050.

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Studies of larval lobster (Homarus americanus) distribution off southwestern Nova Scotia during the summers of 1977 and 1978, were used to estimate an average larval recruitment or production of 1918 and 5284 stage IV lobsters per square kilometre per year inshore and offshore, respectively. Results indicate that the offshore may contribute up to 97% of the larval recruits for the entire southwestern Nova Scotia region. Current patterns and velocities of 3–16 cm∙s−1 were estimated from surface drifter returns within the Gulf of Maine. Limits of larval dispersion are estimated from surface currents in the region and the physiological and ecological traits of the larval lobster. Offshore lobsters could make an important contribution to recruitment not only off southwestern Nova Scotia but in the entire eastern sector of the Gulf of Maine to Casco Bay. Larval dispersal provides another line of evidence that the Gulf of Maine area represents one lobster recruitment center. Our results are consistent with the idea that ontogenic seasonal migration of female lobsters has evolved to locate planktotrophic larvae in warmer shoal areas where growth and survival is optimal and from which ocean currents subsequently disperse a large portion of these larvae to settle over highly productive juvenile grounds.

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Whitfield, C. J., J. Aherne, P. J. Dillon, and S. A. Watmough. "Modelling acidification, recovery and target loads for headwater catchments in Nova Scotia, Canada." Hydrology and Earth System Sciences 11, no. 2 (March 2, 2007): 951–63. http://dx.doi.org/10.5194/hess-11-951-2007.

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Abstract. The response of twenty acid-sensitive headwater catchments in Nova Scotia to acidic deposition was investigated for the period 1850–2100 using a dynamic hydrochemical model (MAGIC: Model of Acidification of Groundwater in Catchments). To ensure robust model simulation, MAGIC was calibrated to the long-term chemical trend in annual lake observations (13–20 years). Model simulations indicated that the surface waters of all twenty catchments acidified to the 1970s but showed subsequent recovery (increases in acid neutralising capacity (ANC) and pH) as sulphate deposition decreased. However, under proposed future emissions reductions (approximately 50% of current deposition) simulated ANC and pH will not return to estimated pre-industrial levels by 2100. An ANC of 20 μmolc L−1 and pH of 5.4 were defined as acceptable chemical thresholds (or critical chemical limits) for aquatic organisms in the current study. Under the proposed emissions reductions only one catchment is predicted to remain below the critical limit for ANC by 2100; three additional catchments are predicted to remain below the critical limit for pH. Dynamic models may be used to estimate target loads, i.e., the required deposition reductions to achieve recovery within a given time. Setting target loads at approximately 30% of current depositions would allow three of the four lakes to reach the chemical criteria by 2030. In contrast to the generally good prognosis for surface waters, soils lost an average of 32% of estimated initial base saturation and recovery is estimated to be very slow, averaging 23% lower than pre-acidification levels in 2100.

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Whitfield, C. J., J. Aherne, P. J. Dillon, and S. A. Watmough. "Modelling acidification, recovery and target loads for headwater catchments in Nova Scotia, Canada." Hydrology and Earth System Sciences Discussions 3, no. 6 (November 29, 2006): 3595–627. http://dx.doi.org/10.5194/hessd-3-3595-2006.

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Abstract. The response of twenty acid-sensitive headwater catchments in Nova Scotia to acidic deposition was investigated for the period 1850–2100 using a dynamic hydrochemical model (MAGIC: Model of Acidification of Groundwater in Catchments). To ensure robust model simulation, MAGIC was calibrated to the long-term chemical trend in annual lake observations (13–20 years). Model simulations indicated that the surface waters of all twenty catchments acidified to the 1970s but showed subsequent recovery (increases in acid neutralising capacity (ANC) and pH) as sulphate deposition decreased. However, under proposed future emissions reductions (approximately 50% of current deposition) simulated ANC and pH will not return to estimated pre-industrial levels by 2100. An ANC of 20 μmolc L−1 and pH of 5.4 were defined as acceptable chemical thresholds (or critical chemical limits) for aquatic organisms in the current study. Under the proposed emissions reductions only one catchment is predicted to remain below the critical limit for ANC by 2100; three additional catchments are predicted to remain below the critical limit for pH. Dynamic models may be used to estimate target loads, i.e., the required deposition reductions to achieve recovery within a given time. Setting target loads at approximately 30% of current depositions would allow three of the four lakes to reach the chemical criteria by 2030. In contrast to the generally good prognosis for surface waters, soils lost an average of 32% of estimated initial base saturation and recovery is estimated to be very slow, averaging 23% lower than pre-acidification levels in 2100.

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Ottensmeyer, C. Andrea, and Hal Whitehead. "Behavioural evidence for social units in long-finned pilot whales." Canadian Journal of Zoology 81, no. 8 (August 1, 2003): 1327–38. http://dx.doi.org/10.1139/z03-127.

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In general, mammal species show geographic or social dispersal by one or both sexes. Long-term behavioural observations and genetic evidence have confirmed that fish-eating resident killer whales, Orcinus orca, are a rare exception. Female and male offspring travel with their mothers for their whole lives: this is natal group philopatry. It is suspected that pilot whales, Globicephala spp., also follow this social pattern, but longitudinal data on the social structure of live long-finned pilot whales, Globicephala melas, are rare. We observed G. melas through July and August of 19982000 off northern Nova Scotia, Canada. Estimated group sizes ranged from 2 to 135 (mean = 20, SD = 17, median = 15, n = 249). We distinguished 322 individuals on the basis of distinctive marks on the dorsal fin, with estimated mark rates of 0.336 (proportion) (SE = 0.041) and 0.352 (mean of estimates) (SE = 0.036). Permutation testing rejected the null hypothesis of random association between individuals (p < 0.0005). The best fit model of the standardized lagged association rate suggests short-term associations of individuals over hours to days and long-term associations with a subset of those individuals over years. When scaled according to mark rate, sets of long-term associates average approximately 1112 individuals, a much lower estimate than that presented previously from drive-fishery data from the Faroe Islands. Genetic sampling of behaviourally studied individuals is recommended.

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Fu, Caihong, Robert Mohn, and L. Paul Fanning. "Why the Atlantic cod (Gadus morhua) stock off eastern Nova Scotia has not recovered." Canadian Journal of Fisheries and Aquatic Sciences 58, no. 8 (August 1, 2001): 1613–23. http://dx.doi.org/10.1139/f01-095.

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An age-structured population dynamics model, incorporating interactions between Atlantic cod (Gadus morhua), the fishery, and the grey seal (Halichoerus grypus) population, was applied to the cod stock off eastern Nova Scotia (Northwest Atlantic Fisheries Organization Divisions 4Vs and 4W, commonly abbreviated to 4VsW), a stock that has dramatically declined since the late 1980s. Mortality was modeled as having three components: fishing mortality (F), seal predation (Mp), and all other sources of natural mortality (M). Specifically, M was assumed to be distinct for immature cod (ages 14; Mi) and mature cod (age 5 and older; Mm), and respective annual variations were estimated. Parameters estimated also included recruitment (cod abundance at age 1; R), F, and Mp. Based on our estimates of F, Mp, and M, it is unlikely that the collapse of the 4VsW cod stock can be attributed to a sudden increase in M; fishing appears to have been the primary cause for the stock's decline. However, after the moratorium on commercial fishing in 1993, increasing Mp and Mm and low R may have contributed to the failure of the 4VsW cod stock to recover.

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Marrie, Ruth Ann, John D. Fisk, Karen J. Stadnyk, Bo Nancy Yu, Helen Tremlett, Christina Wolfson, Sharon Warren, and Virender Bhan. "The Incidence and Prevalence of Multiple Sclerosis in Nova Scotia, Canada." Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 40, no. 6 (November 2013): 824–31. http://dx.doi.org/10.1017/s0317167100015961.

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Background:Estimates of incidence and prevalence are needed to determine disease risk and to plan for health service needs. Although the province of Nova Scotia, Canada is located in a region considered to have a high prevalence of multiple sclerosis (MS), epidemiologic data are limited.Objective:We aimed to validate an administrative case definition for MS and to use this to estimate the incidence and prevalence of MS in Nova Scotia.Methods:We used provincial administrative claims data to identify persons with MS. We validated administrative case definitions using the clinical database of the province's only MS Clinic; agreement between data sources was expressed using a kappa statistic. We then applied these definitions to estimate the incidence and prevalence of MS from 1990 to 2010.Results:We selected the case definition using ≥7 hospital or physician claims when >3 years of data were available, and ≥3 claims where less data were available. Agreement between data sources was moderate (kappa = 0.56), while the positive predictive value was high (89%). In 2010, the age-standardized prevalence of MS per 100,000 population was 266.9 (95% CI: 257.1- 277.1) and incidence was 5.17 (95% CI: 3.78-6.56) per 100,000 persons/year. From 1990-2010 the prevalence of MS rose steadily but incidence remained stable.Conclusions:Administrative data provide a valid and readily available means of estimating MS incidence and prevalence. MS prevalence in Nova Scotia is among the highest in the world, similar to recent prevalence estimates elsewhere in Canada.

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AMITAI, E., X. LLORT, and D. SEMPERE-TORRES. "Comparison of TRMM Radar Rainfall Estimates with NOAA Next-Generation QPE." Journal of the Meteorological Society of Japan 87A (2009): 109–18. http://dx.doi.org/10.2151/jmsj.87a.109.

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Jacobowitz, H., and R. Hucek. "Improvements in broadband planetary albedo estimates from narrowband NOAA satellite observations." Advances in Space Research 14, no. 1 (January 1994): 99–102. http://dx.doi.org/10.1016/0273-1177(94)90355-7.

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Fisk, John D., Susan A. Morehouse, Murray G. Brown, Chris Skedgel, and T. Jock Murray. "Hospital-based Psychiatric Service Utilization and Morbidity in Multiple Sclerosis." Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 25, no. 3 (August 1998): 230–35. http://dx.doi.org/10.1017/s0317167100034065.

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ABSTRACT:Background:Despite the common association of psychiatric morbidity and multiple sclerosis (MS), population-based prevalence estimates of these disorders are limited. Such estimates are of particular importance to those conducting trials of interventions for the treatment of MS. This study examined the prevalence of bipolar disorder, depression, and attempted suicide among hospital service utilizers in Nova Scotia and compared these measures for the MS and non-MS population.Methods:Data regarding diagnosis and utilization were extracted from two linked databases which included all hospital separation records for Nova Scotia over a 3 year period (1992/93-1994/95).Results:The prevalence of bipolar disorder in hospitalized MS patients was 1.97% and depression was 4.27%. These rates were significantly higher than the 0.92% and 2.04%, respectively, for the non-MS hospital utilizers. These diagnoses also accounted for more than half of the primary diagnostic codes for psychiatric service separations by MS patients. The proportion of total hospital utilization which was accounted for by psychiatric services did not differ between MS and non-MS utilizers. While suicide attempts were rare, the estimated frequency of suicide attempts in the total MS population was more than three times that of the general population.Conclusions:Bipolar disorder and depression were twice as prevalent in hospitalized MS patients as in the general population of hospital utilizers while the estimated frequency of suicide attempts was at least three times greater. These results illustrate that psychiatric morbidity and service utilization are important considerations in the care of MS patients.

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Hubley, P. Bradford, and A. Jamie F. Gibson. "A model for estimating mortality of Atlantic salmon, Salmo salar, between spawning events." Canadian Journal of Fisheries and Aquatic Sciences 68, no. 9 (September 2011): 1635–50. http://dx.doi.org/10.1139/f2011-074.

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We developed a Bayesian hierarchical model to estimate annual mortality of repeat-spawning Atlantic salmon, Salmo salar, that distinguishes between mortality rates and the confounding effects of consecutive-year and alternate-year repeat-spawning strategies. The model provides annual estimates of two mortality rates: mortality in the first year (Z1), a time period during which salmon are primarily in freshwater (staging, spawning, and overwintering) followed by a brief period at sea, and mortality in the second year (Z2) when salmon are predominantly at sea. When fit to data for the LaHave River (Nova Scotia, Canada) salmon population, Z1 showed an increasing trend throughout the time series, whereas Z2 also increased but in a single, stepwise manner. Once a time series of mortality rates was separated from the other life-history parameters, we were able to demonstrate how they could be used for examining the influence of environmental conditions by comparing the estimated mortality rate time series with the North Atlantic Oscillation Index (NAOI). This comparison uncovered a statistically significant correlation between the NAOI and the survival in the second year after spawning that would not have been evident had the mortality estimation model not been developed.

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Kiberd, J., C. Burgess, M. McLeod, and K. M. Peltekian. "A41 PERIOD PREVALENCE ESTIMATE OF PRIMARY BILIARY CHOLANGITIS IN NOVA SCOTIA." Journal of the Canadian Association of Gastroenterology 1, suppl_2 (February 2018): 68. http://dx.doi.org/10.1093/jcag/gwy009.041.

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34

Mullin, T. J., E. K. Morgenstern, Y. S. Park, and D. P. Fowler. "Genetic parameters from a clonally replicated test of black spruce (Piceamariana)." Canadian Journal of Forest Research 22, no. 1 (January 1, 1992): 24–36. http://dx.doi.org/10.1139/x92-004.

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A clonally replicated field test of full-sib black spruce (Piceamariana (Mill.) B.S.P.) progeny was established at four locations in Nova Scotia. Estimated variance components for 5-year height growth and survival were interpreted according to an additive–dominance–epistasis genetic model and used to derive estimates of gain from various selection and deployment strategies. Five years after striking, 64% of the total genetic variance for height growth was due to additive variance. Virtually all of the remaining nonadditive variance was composed of epistatic variances; dominance variance was negligible. Narrow-sense heritability for 5-year height growth was low at 0.059. Substantial nonadditive variance contributed to a somewhat higher estimate of broad-sense heritability at 0.093. Family-mean heritabilities were much higher: 0.823 and 0.697 for half-sib and full-sib family means, respectively. Comparable heritabilities for survival were estimated with high standard errors and were considered unreliable. Results from this study indicate that clonal selection may provide large increases in genetic gain by capturing (i) genetic variance due to epistasis and (ii) a greater portion of the additive variance. Genetic gains for 5-year height growth in the order of 22.6% might be achieved using the best 1% of tested clones for operational planting. Clonal propagation may also be a preferred method to capture substantial genetic gain (about 11%) from selection at the family level, resulting in simplified management of breeding populations while reducing costs associated with conventional soil-based orchards.

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Culvenor, RA, RN Oram, and JT Wood. "Inheritance of aluminium tolerance in Phalaris aquatica L." Australian Journal of Agricultural Research 37, no. 4 (1986): 397. http://dx.doi.org/10.1071/ar9860397.

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The inheritance of aluminium tolerance in P. aquatica was investigated in solution culture, and correlations with other screening systems were determined. In the Israeli cultivar, Noy, the difference between the highly sensitive and moderately tolerant classes, which had been resolved in earlier experiments, can be largely explained by a two-gene hypothesis in which tolerance requires at least one dominant allele at each locus. Modifiers of these genes may also be involved. Assuming that the extensive continuous variation within the moderately tolerant class is polygenic, a quantitative inheritance study was conducted in a population of half-sib families in a diverse breeding population, the sensitive class being eliminated on performance in solution. Heritability estimates for relative root extension in solution ranged from 0.48 to 0.75, and estimated response to selection was high. However, heritability estimates for shoot growth of the same plants on a field site high in aluminium were low and non-significant (0.07-0.26). The highest estimate of genetic correlation between solution and field was not significant at 0.56. Variability in soil aluminium concentrations appeared to be a major cause of these low values. Prior screening of the population using a haematoxylin root-staining procedure gave a significant genetic correlation with solution responses (0.48). However, the technique requires further development for screening phalaris. In breeding for improved tolerance, the highly sensitive class could be eliminated by test crossing potential parents with homozygous sensitive plants. Several generations of selection could then be imposed, which, on the basis of genetic parameters estimated from solution screening, should yield a population appreciably more aluminium-tolerant than existing cultivars.

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36

Gupta, Shilpi, Chelsea M. Rose, James Buszkiewicz, Jennifer Otten, Marie L. Spiker, and Adam Drewnowski. "Inedible Food Waste Linked to Diet Quality and Food Spending in the Seattle Obesity Study SOS III." Nutrients 13, no. 2 (January 31, 2021): 479. http://dx.doi.org/10.3390/nu13020479.

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Americans waste about a pound of food per day. Some of this is represented by inedible food waste at the household level. Our objective was to estimate inedible food waste in relation to diet quality and participant socio-economic status (SES). Seattle Obesity Study III participants (n = 747) completed the Fred Hutch Food Frequency Questionnaire (FFQ) and socio-demographic and food expenditure surveys. Education and geo-coded tax-parcel residential property values were measures of SES. Inedible food waste was calculated from diet records. Retail prices of FFQ component foods (n = 378) were used to estimate individual-level diet costs. The NOVA classification was used to identify ultra-processed foods. Multivariable linear regressions tested associations between inedible food waste, SES, food spending, Nutrient Rich Food (NRF9.3) and Healthy Eating Index (HEI-2015) scores. Inedible food waste was estimated at 78.7 g/d, mostly from unprocessed vegetables (32.8 g), fruit (30.5 g) and meat, poultry, and fish (15.4 g). Greater inedible food waste was associated with higher HEI-2015 and NRF9.3 scores, higher food expenditures and lower percent energy from ultra-processed foods. In multivariable models, more inedible food waste was associated with higher food expenditures, education and residential property values. Higher consumption of unprocessed foods were associated with more inedible food waste and higher diet costs. Geo-located estimates of inedible food waste can provide a proxy index of neighborhood diet quality.

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Ögelman, H., J. Krautter, and K. Beuermann. "Exosat Observations of X-Rays from Classical Novae during Outburst Stage." International Astronomical Union Colloquium 93 (1987): 279. http://dx.doi.org/10.1017/s0252921100104981.

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AbstractThe initial discovery of soft X-rays from Nova Muscae 1983 was followed by eight additional observations of the three brightest novae whose outburst stage coincided with the lifetime of EXOSAT satellite; namely three more observations of Nova Muscae 1983, three observations of Nova Vulpeculae 1984 # 1 (PW Vul), and two observations of Nova Vulpeculae 1984 # 2. Through these observations we sampled the soft X-ray light curve of classical novae from optical maximum to ~ 900 days after. The observations seem best explained by the constant bolometric luminosity model of a hot white dwarf remnant. Although the measurements suffer from limited statistics, very broad energy bandpass, and incomplete sampling of any single nova, their constraints on the theories of nova outburst are significant. One constraint is that the lifetime of the white dwarf remnant in Nova Muscae 1983 is ~ 2 to 3 years, which leads to the conclusion that the burned envelope mass Mburn should be of the order of . The second constraint is that the maximum temperature, of the white dwarf remnant should approximately be within 200 000 K to 400 000 K. We estimate that a white dwarf remnant evolving like the central star of a planetary nebula, with core mass of 0.8 to 0.9 M⊙, core luminosity of ~ 2 × 104L⊙, and envelope mass of 10−6M⊙, can explain the general characteristics of the X-ray measurements for Nova Muscae 1983. In order to have ≥ 1.1 M⊙ core mass, estimated from the early observations of bolometric luminosity in the UV to infrared range, a wind with Ṁ ≤ 5 × 10−7M⊙yr−1 appears to be necessary. The few observations of Nova Vulpeculae 1984 # 1 and Nova Vulpeculae 1984 # 2 , during the first year after outburst, give a risetime and intensity that is consistent with a constant bolometric luminosity model.

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Loeb, Norman G., and Natividad Manalo-Smith. "Top-of-Atmosphere Direct Radiative Effect of Aerosols over Global Oceans from Merged CERES and MODIS Observations." Journal of Climate 18, no. 17 (September 1, 2005): 3506–26. http://dx.doi.org/10.1175/jcli3504.1.

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Abstract The direct radiative effect of aerosols (DREA) is defined as the difference between radiative fluxes in the absence and presence of aerosols. In this study, the direct radiative effect of aerosols is estimated for 46 months (March 2000–December 2003) of merged Clouds and the Earth’s Radiant Energy System (CERES) and Moderate Resolution Imaging Spectroradiometer (MODIS) Terra global measurements over ocean. This analysis includes the contribution from clear regions in both clear and partly cloudy CERES footprints. MODIS–CERES narrow-to-broadband regressions are developed to convert clear-sky MODIS narrowband radiances to broadband shortwave (SW) radiances, and CERES clear-sky angular distribution models (ADMs) are used to estimate the corresponding top-of-atmosphere (TOA) radiative fluxes that are needed to determine the DREA. Clear-sky MODIS pixels are identified using two independent cloud masks: (i) the NOAA/National Environmental Satellite, Data, and Information Service (NESDIS) algorithm that is used for inferring aerosol properties from MODIS on the CERES Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product (NOAA SSF); and (ii) the standard algorithm that is used by the MODIS aerosol group to produce the MODIS aerosol product (MOD04). Over global oceans, direct radiative cooling by aerosols for clear scenes that are identified from MOD04 is estimated to be 40% larger than for clear scenes from NOAA SSF (5.5 compared to 3.8 W m−2). Regionally, differences are largest in areas that are affected by dust aerosol, such as oceanic regions that are adjacent to the Sahara and Saudi Arabian deserts, and in northern Pacific Ocean regions that are influenced by dust transported from Asia. The net total-sky (clear and cloudy) DREA is negative (cooling) and is estimated to be −2.0 W m−2 from MOD04, and −1.6 W m−2 from NOAA SSF. The DREA is shown to have pronounced seasonal cycles in the Northern Hemisphere and large year-to-year fluctuations near deserts. However, no systematic trend in deseasonalized anomalies of the DREA is observed over the 46-month time series that is considered.

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Dutta, Amit Kumar. "MBER Criterion Assisted Power NOMA Design and Performance Analysis With Estimated Channel." IEEE Transactions on Vehicular Technology 68, no. 12 (December 2019): 11816–26. http://dx.doi.org/10.1109/tvt.2019.2944767.

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40

Bullock, Paul R. "Operational Estimates of Western Canadian Grain Production Using NOAA AVHRR LAC Data." Canadian Journal of Remote Sensing 18, no. 1 (January 1992): 23–28. http://dx.doi.org/10.1080/07038992.1992.10855139.

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41

Di Bella, C. M., C. M. Rebella, and J. M. Paruelo. "Evapotranspiration estimates using NOAA AVHRR imagery in the Pampa region of Argentina." International Journal of Remote Sensing 21, no. 4 (January 1, 2000): 791–97. http://dx.doi.org/10.1080/014311600210579.

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42

Hooghiemstra, P. B., M. C. Krol, P. Bergamaschi, A. T. J. de Laat, G. R. van der Werf, P. C. Novelli, M. N. Deeter, I. Aben, and T. Röckmann. "Comparing optimized CO emission estimates using MOPITT or NOAA surface network observations." Journal of Geophysical Research: Atmospheres 117, no. D6 (March 27, 2012): n/a. http://dx.doi.org/10.1029/2011jd017043.

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43

de Wit, A. J. W., H. L. Boogaard, and C. A. van Diepen. "Using NOAA–AVHRR estimates of land surface temperature for regional agrometeorogical modelling." International Journal of Applied Earth Observation and Geoinformation 5, no. 3 (September 2004): 187–204. http://dx.doi.org/10.1016/j.jag.2004.03.003.

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44

de Freitas Pacheco, J. A., R. Dell'Aglio, D. Costa, and S. J. Codina-Landaberry. "Chemical Composition of Nova Centauri 1986." International Astronomical Union Colloquium 122 (1990): 206–7. http://dx.doi.org/10.1017/s0252921100068639.

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We have obtained extensive spectroscopic observations of Nova Cen 1986 at different phases of the event.From the observed Hα/Hβ line ratio we derived a colour excess EB-V = 0m.54. Using the empirical relationship between the fading time and the absolute magnitude at maximum light as well as the width of the Nal interstellar lines, we estimated for the nova a distance of 1.2 ± 0.2 kpc. The full-width of non-blended lines at the nebular phase indicates an expansion velocity of 1400 ± 120 km s−1The temporal behaviour of the Hβ emission suggests that the electron density varies with time as Ne ∝ t−3, i.e., the shell evolves more or less homologously. The electron temperature was estimated from the [NII] and [OIII] line ratios. In the O+2 region the electron temperature is in the range 14100 ± 1200 K. The N+ region has a lower temperature, T ≃ 8000 K around day 142 after maximum light. The N+ temperature increases in this region as the shell evolves and attains the same values observed in the O+2 region around days 300-470.

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Nóia Júnior, Rogério De Souza, Clyde William Fraisse, Vinicius Andrei Cerbaro, Mauricio Alex Z. Karrei, and Noemi Guindin. "Evaluation of the Hargreaves-Samani Method for Estimating Reference Evapotranspiration with Ground and Gridded Weather Data Sources." Applied Engineering in Agriculture 35, no. 5 (2019): 823–35. http://dx.doi.org/10.13031/aea.13363.

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Abstract. Methods of estimating evapotranspiration require weather variables as their main input data. Thus, the lack of full weather data sets is one of the main challenges for evaluating and mitigating the effects of climate variability and climate change on agricultural production systems. The Hargreaves-Samani method (HS) is one of the ways to estimate reference evapotranspiration (ETo) when only temperature observations are available, which is a common situation in many agricultural enterprises. Another possible option for regions not served by weather stations is the use of gridded weather data (GWD). Based on that, the main objective of this study was to evaluate the performance of the HS method to estimate ETo in different regions of the United States, as well as to assess the suitability of two gridded weather data (PRISM and NOAA-RTMA) sources to estimate ETo by comparing the results obtained to ETo estimated by the Penman-Monteith (FAO-PM) method, which is the recommended methodology by FAO Irrigation and Drainage Paper 56 when all weather variables are available. Weather observations were obtained for 17 locations across the United States representing regions with subtropical humid and semi-arid continental climates, considering the period of one year (2017). These observations were used to estimate daily ETo with the HS and Penman-Monteith methods. Our results demonstrated that the HS method performance varied according to the location and month of the year. Due to the high relative humidity (RH) during the winter, and high air temperature (Ta) during the summer, the locations selected in the state of Florida, presented the worst performance. The HS method performed well in many other locations such as Froid – MT. Also, the estimation of ETo by HS method and by using PRISM and NOAA-RTMA gridded weather databases showed a good agreement with the ETo estimated by FAO-PM based on weather station observations. Keywords: Penman-Monteith, PRISM, RTMA, Water Management.

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HAYHOE, H. N., C. TARNOCAI, and L. M. DWYER. "SOIL MANAGEMENT AND VEGETATION EFFECTS ON MEASURED AND ESTIMATED SOIL THERMAL REGIMES IN CANADA." Canadian Journal of Soil Science 70, no. 1 (February 1, 1990): 61–71. http://dx.doi.org/10.4141/cjss90-007.

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Observations at sites in British Columbia, the Yukon, Manitoba and Nova Scotia over a range of soils, managements and vegetation were used to assess variation in soil temperature. The annual soil temperature regime was compared with estimates derived from a macroclimate model which was developed for mineral soils that are level, well to moderately well drained, and covered by short grass. In general, this study showed the dampening effect of vegetation cover on soil temperature and suggested the further dampening effect of an organic layer on the soil surface. However, soil temperatures for cultivated and grass sites were not significantly different (P ≥ 0.05) from the estimates made using the macroclimate model. In contrast, forested sites had significantly (P ≤ 0.05) colder soil temperatures than those estimated by the model. The mean annual and mean summer 0.50 m soil temperatures were, respectively, 1.3 and 3.2 °C colder than the corresponding estimates. Key words: Soil thermal regimes, estimation of soil temperature, mean annual soil temperature

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Farley, Elise, Modupe Juliana Oyemakinde, Jorien Schuurmans, Cono Ariti, Fatima Saleh, Gloria Uzoigwe, Karla Bil, et al. "The prevalence of noma in northwest Nigeria." BMJ Global Health 5, no. 4 (April 2020): e002141. http://dx.doi.org/10.1136/bmjgh-2019-002141.

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BackgroundNoma, a rapidly progressing infection of the oral cavity, mainly affects children. The true burden is unknown. This study reports estimated noma prevalence in children in northwest Nigeria.MethodsOral screening was performed on all ≤15 year olds, with caretaker consent, in selected households during this cross-sectional survey. Noma stages were classified using WHO criteria and caretakers answered survey questions. The prevalence of noma was estimated stratified by age group (0–5 and 6–15 years). Factors associated with noma were estimated using logistic regression.ResultsA total of 177 clusters, 3499 households and 7122 children were included. In this sample, 4239 (59.8%) were 0–5 years and 3692 (52.1%) were female. Simple gingivitis was identified in 3.1% (n=181; 95% CI 2.6 to 3.8), acute necrotising gingivitis in 0.1% (n=10; CI 0.1 to 0.3) and oedema in 0.05% (n=3; CI 0.02 to 0.2). No cases of late-stage noma were detected. Multivariable analysis in the group aged 0–5 years showed having a well as the drinking water source (adjusted odds ratio (aOR) 2.1; CI 1.2 to 3.6) and being aged 3–5 years (aOR 3.9; CI 2.1 to 7.8) was associated with being a noma case. In 6–15 year olds, being male (aOR 1.5; CI 1.0 to 2.2) was associated with being a noma case and preparing pap once or more per week (aOR 0.4; CI 0.2 to 0.8) was associated with not having noma. We estimated that 129120 (CI 105294 to 1 52 947) individuals <15 years of age would have any stage of noma at the time of the survey within the two states. Most of these cases (93%; n=120 082) would be children with simple gingivitis.ConclusionsOur study identified a high prevalence of children at risk of developing advanced noma. This disease is important but neglected and therefore merits inclusion in the WHO neglected tropical diseases list.

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Maggioni, Viviana, Mathew R. P. Sapiano, Robert F. Adler, Yudong Tian, and George J. Huffman. "An Error Model for Uncertainty Quantification in High-Time-Resolution Precipitation Products." Journal of Hydrometeorology 15, no. 3 (June 1, 2014): 1274–92. http://dx.doi.org/10.1175/jhm-d-13-0112.1.

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Abstract This study proposes a new framework, Precipitation Uncertainties for Satellite Hydrology (PUSH), to provide time-varying, global estimates of errors for high-time-resolution, multisatellite precipitation products using a technique calibrated with high-quality validation data. Errors are estimated for the widely used Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) 3B42 product at daily/0.25° resolution, using the NOAA Climate Prediction Center (CPC) Unified gauge dataset as the benchmark. PUSH estimates the probability distribution of reference precipitation given the satellite observation, from which the error can be computed as the difference (or ratio) between the satellite product and the estimated reference. The framework proposes different modeling approaches for each combination of rain and no-rain cases: correct no-precipitation detection (both satellite and gauges measure no precipitation), missed precipitation (satellite records a zero, but the gauges detect precipitation), false alarm (satellite detects precipitation, but the reference is zero), and hit (both satellite and gauges detect precipitation). Each case is explored and explicitly modeled to create a unified approach that combines all four scenarios. Results show that the estimated probability distributions are able to reproduce the probability density functions of the benchmark precipitation, in terms of both expected values and quantiles of the distribution. The spatial pattern of the error is also adequately reproduced by PUSH, and good agreement between observed and estimated errors is observed. The model is also able to capture missed precipitation and false detection uncertainties, whose contribution to the total error can be significant. The resulting error estimates could be attached to the corresponding high-resolution satellite precipitation products.

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Canisius, F., H. Turral, and D. Molden. "Fourier analysis of historical NOAA time series data to estimate bimodal agriculture." International Journal of Remote Sensing 28, no. 24 (December 20, 2007): 5503–22. http://dx.doi.org/10.1080/01431160601086043.

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Wood, J., and C. S. Crawford. "An estimate of the system parameters in the dwarf nova IP Peg." Monthly Notices of the Royal Astronomical Society 222, no. 4 (October 1, 1986): 645–54. http://dx.doi.org/10.1093/mnras/222.4.645.

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Journal articles on the topic 'Estimateur à noya'

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