scholarly journals Meteosat and GOES-East Imager Visible Channel Calibration

2004 ◽  
Vol 21 (11) ◽  
pp. 1701-1709 ◽  
Author(s):  
Pierre Le Borgne ◽  
Gérard Legendre ◽  
Anne Marsouin
Keyword(s):  
Solar Irradiance ◽  
Degradation Rate ◽  
Radiant Energy ◽  
Energy System ◽  
Mean Value ◽  
Calibration Coefficient ◽  
Pragmatic Approach ◽  
Monthly Basis ◽  
Preliminary Step ◽  
Short Period

Abstract As a preliminary step to solar irradiance calculations, the Centre de Météorologie Spatiale (CMS) has developed a pragmatic approach to calibrate the visible channels of Meteosat and GOES-East imagers. The responsivity of the Meteosat visible channel has been monitored with three desert targets from 1989 to 2002. The annual degradation rate has been estimated to 1.8% for Meteosat-4, 1.4% for Meteosat-5, and 1.9% for Meteosat-7. A reference calibration coefficient for Meteosat-7 has been derived from a comparison with Clouds and Earth's Radiant Energy System (CERES) data in summer 1998. Meteosat and GOES-East data corresponding to homogenous pixels along longitude 37.5°W and around 1200 LST have been compared on a monthly basis, leading to a calibration of GOES-East visible channel. GOES-8 data have been processed from June 1998 to December 2002 and the annual degradation rate obtained during this period is 4.0%. GOES-12 data have been processed from April to August 2003. During this short period, no degradation rate can be estimated but only a mean value of the calibration coefficient, which corresponds to a 7% increase of the prelaunch coefficient.

Variations of Climate, Surface Energy Budget, and Minimum Snow/Ice Extent over Canadian Arctic Landmass for 2000–16

2018 ◽  
Vol 31 (3) ◽  
pp. 1155-1172 ◽  
Author(s):  
Alexander P. Trishchenko ◽  
Shusen Wang
Keyword(s):  
Radiant Energy ◽  
Canadian Arctic ◽  
Warm Season ◽  
Correlation Coefficients ◽  
Energy System ◽  
Mean Value ◽  
Surface Energy Budget ◽  
Local Climate ◽  
Average Value ◽  
Snow And Ice

Abstract Snow and ice over land are important hydrological resources and sensitive indicators of climate change. The Moderate Resolution Imaging Spectroradiometer (MODIS) dataset at 250-m spatial resolution generated at the Canada Centre for Remote Sensing (CCRS) is used to derive the annual minimum snow and ice (MSI) extent over the Canadian Arctic landmass over a 17-yr time span (2000–16). The smallest MSI extent (1.53 × 105 km2) was observed in 2012, the largest (2.09 × 105 km2) was observed in 2013; the average value was 1.70 × 105 km2. Several reanalyses and observational datasets are assessed to explain the derived MSI variations: the ERA-Interim reanalysis, North American Regional Reanalysis (NARR), Clouds and the Earth’s Radiant Energy System (CERES) radiative fluxes, and European Space Agency’s GlobSnow dataset. Comparison with the Randolph Glacier Inventory (RGI) showed two important facts: 1) the semipermanent snowpack in the Canadian Arctic that persists through the entire melting season is a significant component relative to the ice caps and glacier-covered areas (up to 36% or 5.58 × 104 km2), and 2) the MSI variations are related to variations in the local climate dynamics such as warm season average temperature, energy fluxes, and snow cover. The correlation coefficients (absolute values) can be as high as 0.77. The reanalysis-based MSI estimates agree with satellite MSI results (average bias of 2.2 × 103 km2 or 1.3% of the mean value).

Evaluation of net shortwave radiation over China with a regional climate model

2020 ◽  
Vol 80 (2) ◽  
pp. 147-163
Author(s):  
X Liu ◽  
Y Kang ◽  
Q Liu ◽  
Z Guo ◽  
Y Chen ◽  
...  
Keyword(s):  
Regional Climate Model ◽  
Climate Model ◽  
Regional Climate ◽  
Radiant Energy ◽  
Energy System ◽  
Radiation Budget ◽  
Shortwave Radiation ◽  
Monsoon Region ◽  
Clear Sky ◽  
Sky Conditions

The regional climate model RegCM version 4.6, developed by the European Centre for Medium-Range Weather Forecasts Reanalysis, was used to simulate the radiation budget over China. Clouds and the Earth’s Radiant Energy System (CERES) satellite data were utilized to evaluate the simulation results based on 4 radiative components: net shortwave (NSW) radiation at the surface of the earth and top of the atmosphere (TOA) under all-sky and clear-sky conditions. The performance of the model for low-value areas of NSW was superior to that for high-value areas. NSW at the surface and TOA under all-sky conditions was significantly underestimated; the spatial distribution of the bias was negative in the north and positive in the south, bounded by 25°N for the annual and seasonal averaged difference maps. Compared with the all-sky condition, the simulation effect under clear-sky conditions was significantly better, which indicates that the cloud fraction is the key factor affecting the accuracy of the simulation. In particular, the bias of the TOA NSW under the clear-sky condition was <±10 W m-2 in the eastern areas. The performance of the model was better over the eastern monsoon region in winter and autumn for surface NSW under clear-sky conditions, which may be related to different levels of air pollution during each season. Among the 3 areas, the regional average biases overall were largest (negative) over the Qinghai-Tibet alpine region and smallest over the eastern monsoon region.

scholarly journals Coloration determination of spectral darkening occurring on a broadband Earth observing radiometer: application to Clouds and the Earth's Radiant Energy System (CERES)

2006 ◽  
Author(s):  
Grant Matthews ◽  
Kory Priestley ◽  
Norman G. Loeb ◽  
Konstantin Loukachine ◽  
Susan Thomas ◽  
...  
Keyword(s):  
Radiant Energy ◽  
Energy System

Shear velocity from differential travel times of short-period ScS-P in New Hebrides, Fiji-Tonga, and Banda Sea regions

1975 ◽  
Vol 65 (6) ◽  
pp. 1787-1796
Author(s):  
Mansur A. Choudhury ◽  
Georges Poupinet ◽  
Guy Perrier
Keyword(s):  
Upper Mantle ◽  
Focal Depth ◽  
Shear Velocity ◽  
Mean Value ◽  
Travel Times ◽  
Velocity Models ◽  
Depth Dependence ◽  
Short Period ◽  
New Hebrides ◽  
The Antarctic

abstract Behavior of P, S and ScS residuals as well as those of differential travel times of ScS-P from the Jeffreys-Bullen tables are analyzed. The phases have been read from short-period records of the Antarctic station, Dumont d'Urville (DRV); the earthquakes originating in New Hebrides, Fiji-Tonga, and Banda Sea regions. P residuals from all regions show a mean value of about −1 sec. On the contrary, S and ScS residuals, well correlated among themselves, show important regional as well as focal-depth dependence. ScS-P residuals from shallow and intermediate shocks are largely positive for New Hebrides and largely negative for Banda Sea; those from intermediate shocks are moderately positive for Fiji-Tonga. The anomalies disappear at depths greater than about 200 km. Upper mantle shear velocity models are presented for the three regions. The models are discussed in relation to a sinking lithosphere.

A Comparative Study between Conventional and Modified Leishman Stain

2021 ◽  
Vol 8 (2) ◽  
pp. 5-12
Author(s):  
Rizwana Abdul Hye ◽  
Bindiya Gisuthan ◽  
Indira Kariveettil
Keyword(s):  
Conventional Method ◽  
Peripheral Blood ◽  
Cross Sectional Study ◽  
Mean Value ◽  
Health Care Centre ◽  
Cross Sectional ◽  
Modified Method ◽  
Present Cross Sectional Study ◽  
Short Period

Introduction: Leishman stain has been used as the stain of choice for peripheral blood films since many decades .But it has a disadvantage of consuming 15 minutes for the procedure alone thereby increasing the turn around time of peripheral smear reporting. In this study modified Leishman stain was made by adding phenol to conventional Leishman to reduce the staining time to 3 minutes without interfering with the quality of stain. Aim: To study the quality of modified Leishman stain in comparison with conventional preparation on peripheral blood smears. Materials and Methods: The present cross-sectional study was carried out in Central Haematology laboratory of a tertiary health care centre in Southern India. A pilot study was done to determine the ideal ratio of phenol to Leishman powder in preparing modified stain without compromising the staining quality. After obtaining consent, the blood sample was collected in anticoagulated vials. Sample size was calculated to be 85.Two thin wedge smears were prepared from each sample and one was stained with conventional Leishman stain and other with modified Leishman stain. The staining characteristics were assessed and scored by an experienced pathologist in terms of 6 parameters- RBC pattern, nuclear pattern, neutrophil granules, eosinophil granules, platelets and background staining. The grades were 1, 2, 3 & 4 (poor, satisfied, good and excellent). Smears each with grades 2, 3 and 4 were selected for study. The results were analysed by Statistical Package for the Social Sciences (SPSS) software version 16.0. Result: The mean value for the staining quality using conventional method was 4.73 and for modified method was 5.39, and the total score possible is 6. Photomicrograph showed excellent results with modified Leishman stain. Thus from these values we can interpret that modified method gave much more acceptable results than that of conventional method. Conclusion: Unlike the conventional method which requires a total of 15 minutes, to complete the staining process, modified Leishman staining techniques takes only 3 minutes. Blood films can be stained within a short period of time thus aiding in rapid diagnosis and treatment of patients. Keywords: Leishman stain, Modified Leishman stain, Phenol.

Clouds and Earth radiant energy system: an overview

2004 ◽  
Vol 33 (7) ◽  
pp. 1125-1131 ◽  
Author(s):  
G.Louis Smith ◽  
Bruce A. Wielicki ◽  
Bruce R. Barkstrom ◽  
Robert B. Lee ◽  
Kory J. Priestley ◽  
...  
Keyword(s):  
Radiant Energy ◽  
Energy System

Characterization of the clouds and the Earth's radiant energy system (CERES) sensors on Terra and Aqua spacecraft

2010 ◽  
Author(s):  
Susan Thomas ◽  
K. J. Priestley ◽  
N. M. Smith ◽  
N. G. Loeb ◽  
P. C. Hess ◽  
...  
Keyword(s):  
Radiant Energy ◽  
Energy System
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