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Norman G Loeb - One of the best experts on this subject based on the ideXlab platform.
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surface irradiances of edition 4 0 clouds and the earth s Radiant Energy system ceres Energy balanced and filled ebaf data product
Journal of Climate, 2018Co-Authors: Seiji Kato, David R Doelling, Norman G Loeb, Fred G Rose, David A Rutan, Tyler J Thorsen, Xianglei Huang, William L Smith, Wenying SuAbstract:AbstractThe algorithm to produce the Clouds and the Earth’s Radiant Energy System (CERES) Edition 4.0 (Ed4) Energy Balanced and Filled (EBAF)-surface data product is explained. The algorithm forces...
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clouds and the earth s Radiant Energy system ceres Energy balanced and filled ebaf top of atmosphere toa edition 4 0 data product
Journal of Climate, 2018Co-Authors: Norman G Loeb, David R Doelling, Fred G Rose, Wenying Su, Joseph G Corbett, Hailan Wang, Cathy Nguyen, Lusheng Liang, Cristian Mitrescu, Seiji KatoAbstract:AbstractThe Clouds and the Earth’s Radiant Energy System (CERES) Energy Balanced and Filled (EBAF) top-of-atmosphere (TOA), Edition 4.0 (Ed4.0), data product is described. EBAF Ed4.0 is an update to EBAF Ed2.8, incorporating all of the Ed4.0 suite of CERES data product algorithm improvements and consistent input datasets throughout the record. A one-time adjustment to shortwave (SW) and longwave (LW) TOA fluxes is made to ensure that global mean net TOA flux for July 2005–June 2015 is consistent with the in situ value of 0.71 W m−2. While global mean all-sky TOA flux differences between Ed4.0 and Ed2.8 are within 0.5 W m−2, appreciable SW regional differences occur over marine stratocumulus and snow/sea ice regions. Marked regional differences in SW clear-sky TOA flux occur in polar regions and dust areas over ocean. Clear-sky LW TOA fluxes in EBAF Ed4.0 exceed Ed2.8 in regions of persistent high cloud cover. Owing to substantial differences in global mean clear-sky TOA fluxes, the net cloud radiative eff...
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Clouds and Earth Radiant Energy System: From Design to Data
IEEE Transactions on Geoscience and Remote Sensing, 2014Co-Authors: George Louis Smith, Kory J. Priestley, Norman G LoebAbstract:The Clouds and the Earth's Radiant Energy System (CERES) project has instruments aboard the Terra and Aqua spacecraft that have provided a decade of radiation budget data. In October 2011, the CERES flight model 5 was placed in orbit on the NPOESS Preparatory Project spacecraft. Data from these instruments are being used to investigate the radiation balance of the Earth at various time and space scales and the role of clouds in this balance. The design and calibration, both on the ground and in-orbit, and operation of the instrument are discussed.
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performance assessment of the clouds and the earth s Radiant Energy system ceres instruments aboard terra and aqua spacecraft
Proceedings of SPIE, 2013Co-Authors: Susan Thomas, Norman G Loeb, N M Smith, Kory J. Priestley, Phillip C Hess, Robert S Wilson, Dale R Walikainen, M Shankar, Nitchie SmithAbstract:Clouds and the Earth's Radiant Energy System (CERES) instruments were designed to measure the reflected shortwave and emitted longwave radiances of the Earth’s radiation budget and to investigate the cloud interactions with global radiances for the long-term monitoring of Earth's climate. The three scanning thermistor bolometer sensors on CERES measure broadband radiances in the shortwave (0.3 to 5.0 micrometer), total (0.3 to A rigorous and comprehensive radiometric calibration and validation protocol comprising of various studies was developed to evaluate the calibration accuracy of the CERES instruments. The in-flight calibration of CERES sensors are carried out using the internal calibration module (ICM) comprising of blackbody sources and quartzhalogen tungsten lamp, and a solar diffuser plate known as the Mirror Attenuator Mosaic (MAM). The ICM calibration results are instrumental in determining the changes in CERES sensors’ gains after launch from the prelaunch determined values and the on-orbit gain variations. In addition to the broadband response changes derived from the on-board blackbody and the tungsten lamp, the shortwave and the total sensors show a spectrally dependent drop in responsivity in the shorter wavelegth region below one micron that were brought to light through validation studies. The spectrally dependent changes were attributed to the instrument operational modes and the corrections were derived using the sensor radiance comparisons. This paper covers the on-orbit behavior of CERES sensors aboard the Terra and Aqua spacecraft and the determination of the sensor response changes utilising the in-flight calibration and the radiance measurement comparisons viewing various targets. The corrections for the sensor response changes were incorporated in the radiance calculations of CERES Edition3 data products.
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angular distribution models for top of atmosphere radiative flux estimation from the clouds and the earth s Radiant Energy system instrument on the terra satellite
2011Co-Authors: N M Smith, Konstantin Loukachine, S. Kato, Norman G LoebAbstract:The Clouds and Earth's Radiant Energy System (CERES) provides coincident global cloud and aerosol properties together with reflected solar, emitted terrestrial longwave and infrared window radiative fluxes. These data are needed to improve our understanding and modeling of the interaction between clouds, aerosols and radiation at the top of the atmosphere, surface, and within the atmosphere. This paper describes the approach used to estimate top-of-atmosphere (TOA) radiative fluxes from instantaneous CERES radiance measurements on the Terra satellite. A key component involves the development of empirical angular distribution models (ADMs) that account for the angular dependence of Earth's radiation field at the TOA. The CERES Terra ADMs are developed using 24 months of CERES radiances, coincident cloud and aerosol retrievals from the Moderate Resolution Imaging Spectroradiometer (MODIS), and meteorological parameters from the Global Modeling and Assimilation Office (GMA0) s Goddard Earth Observing System DAS (GEOS-DAS V4.0.3) product. Scene information for the ADMs is from MODIS retrievals and GEOS-DAS V4.0.3 properties over ocean, land, desert and snow, for both clear and cloudy conditions. Because the CERES Terra ADMs are global, and far more CERES data is available on Terra than was available from CERES on the Tropical Rainfall Measuring Mission (TRMM), the methodology used to define CERES Terra ADMs is different in many respects from that used to develop CERES TRMM ADMs, particularly over snow/sea-ice, under cloudy conditions, and for clear scenes over land and desert.
Kory J. Priestley - One of the best experts on this subject based on the ideXlab platform.
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radiometric calibration and performance trends of the clouds and earth s Radiant Energy system ceres instrument sensors onboard the terra and aqua spacecraft
Sensors Systems and Next-Generation Satellites XIX, 2015Co-Authors: M Shankar, Kory J. Priestley, Susan Thomas, Nitchie Smith, Nathaniel P Smith, Dale R WalikainenAbstract:The Clouds and Earth’s Radiant Energy System (CERES) instruments help to study the impact of clouds on the earth's radiation budget. There are currently five instruments- two each on board Aqua and Terra spacecraft and one on the Suomi NPP spacecraft to measure the earth’s reflected shortwave and emitted longwave Energy, which represent two components of the earth’s radiation Energy budget. Flight Models (FM) 1 and 2 are on Terra, FM 3 and 4 are on Aqua, and FM5 is on Suomi NPP. The measurements are made by three sensors on each instrument: a shortwave sensor that measures the 0.3-5 microns wavelength band, a window sensor that measures the water vapor window between 8-12 microns, and a total sensor that measures all incident Energy (0.3- >100 microns). The required accuracy of CERES measurements of 0.5% in the longwave and 1% in the shortwave is achieved through an extensive pre-launch ground calibration campaign as well as on-orbit calibration and validation activities. Onorbit calibration is carried out using the Internal Calibration Module (ICM) that consists of a tungsten lamp, blackbodies, and a solar diffuser known as the Mirror Attenuator Mosaic (MAM). The ICM calibration provides information about the stability of the sensors’ broadband radiometric gains on-orbit. Several validation studies are conducted in order to monitor the behavior of the instruments in various spectral bands. The CERES Edition-4 data products for the FM1-FM4 instruments incorporate the latest calibration methodologies to improve on the Edition-3 data products. In this paper, we discuss the updated calibration methodology and present some validation studies to demonstrate the improvement in the trends using the CERES Edition-4 data products for all four instruments.
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assessment of the clouds and the earth s Radiant Energy system ceres instrument performance and stability on the aqua terra and s npp spacecraft
Proceedings of SPIE, 2015Co-Authors: Nathaniel P Smith, N M Smith, Susan Thomas, Phillip C Hess, Robert S Wilson, Dale R Walikainen, M Shankar, Kory J. PriestleyAbstract:The Clouds and the Earth’s Radiant Energy System (CERES) scanning radiometer is designed to measure reflected solar radiation and thermal radiation emitted by the Earth. Five CERES instruments are currently taking active measurements in-orbit with two aboard the Terra spacecraft (FM1 and FM2), two aboard the Aqua spacecraft (FM3 and FM4), and one aboard the S-NPP spacecraft (FM5). The CERES instrument uses three scanning thermistor bolometers to make broadband radiance measurements in the shortwave (0.3 – 5.0 micrometers), total (0.3 - >100 micrometers) and water vapor window (8 – 12 micrometer) regions. An internal calibration module (ICM) used for in-flight calibration is built into the CERES instrument package consisting of an anodized aluminum blackbody source for calibrating the total and window sensors, and a shortwave internal calibration source (SWICS) for the shortwave sensor. The ICM sources, along with a solar diffusor called the Mirror Attenuator Mosaic (MAM), are used to define shifts or drifts in the sensor response over the life of the mission. In addition, validation studies are conducted to understand any spectral changes that may occur with the sensors and assess the pointing accuracy of the instrument, allowing for corrections to be made to the radiance calculations in CERES data products. This paper covers the observed trends in the internal and solar calibration data, discusses the latest techniques used to correct for sensor response, and explains the validation studies used to assess the performance and stability of the instrument.
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on orbit stability and performance of the clouds and earth s Radiant Energy system ceres instrument sensors onboard the aqua and terra spacecraft
Proceedings of SPIE, 2014Co-Authors: M Shankar, Kory J. Priestley, Susan Thomas, Nitchie Smith, Dale R WalikainenAbstract:The Clouds and Earth’s Radiant Energy System (CERES) instruments onboard the Terra and Aqua spacecraft are part of the NASA Earth Observing System (EOS) constellation to make long-term observations of the earth. CERES measures the earth-reflected shortwave Energy as well as the earth-emitted thermal Energy, which are two components of the earth’s radiation Energy budget. These measurements are made by five instruments- Flight Models (FM) 1 and 2 onboard Terra, FMs 3 and 4 onboard Aqua and FM5 onboard Suomi NPP. Each instrument comprises three sensors that measure the radiances in different wavelength bands- a shortwave sensor that measures in the 0.3 to 5 micron band, a total sensor that measures all the incident Energy (0.3-200 microns) and a window sensor that measures the water-vapor window region of 8 to 12 microns. The stability of the sensors is monitored through on-orbit calibration and validation activities. On-orbit calibration is carried out using the Internal Calibration Module (ICM) that consists of a tungsten lamp, blackbodies, and a solar diffuser known as the Mirror Attenuator Mosaic (MAM). The ICM calibration provides information about the stability of the sensors’ broadband radiometric gains on-orbit. Several validation studies are conducted in order to monitor the behavior of the instruments in various spectral bands. The CERES Edition-4 data products for FM1-FM4 incorporate the latest corrections to the sensor responses using the calibration techniques. In this paper, we present the on-orbit performance stability as well as some validation studies used in deriving the CERES Edition-4 data products from all four instruments.
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Clouds and Earth Radiant Energy System: From Design to Data
IEEE Transactions on Geoscience and Remote Sensing, 2014Co-Authors: George Louis Smith, Kory J. Priestley, Norman G LoebAbstract:The Clouds and the Earth's Radiant Energy System (CERES) project has instruments aboard the Terra and Aqua spacecraft that have provided a decade of radiation budget data. In October 2011, the CERES flight model 5 was placed in orbit on the NPOESS Preparatory Project spacecraft. Data from these instruments are being used to investigate the radiation balance of the Earth at various time and space scales and the role of clouds in this balance. The design and calibration, both on the ground and in-orbit, and operation of the instrument are discussed.
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performance assessment of the clouds and the earth s Radiant Energy system ceres instruments aboard terra and aqua spacecraft
Proceedings of SPIE, 2013Co-Authors: Susan Thomas, Norman G Loeb, N M Smith, Kory J. Priestley, Phillip C Hess, Robert S Wilson, Dale R Walikainen, M Shankar, Nitchie SmithAbstract:Clouds and the Earth's Radiant Energy System (CERES) instruments were designed to measure the reflected shortwave and emitted longwave radiances of the Earth’s radiation budget and to investigate the cloud interactions with global radiances for the long-term monitoring of Earth's climate. The three scanning thermistor bolometer sensors on CERES measure broadband radiances in the shortwave (0.3 to 5.0 micrometer), total (0.3 to A rigorous and comprehensive radiometric calibration and validation protocol comprising of various studies was developed to evaluate the calibration accuracy of the CERES instruments. The in-flight calibration of CERES sensors are carried out using the internal calibration module (ICM) comprising of blackbody sources and quartzhalogen tungsten lamp, and a solar diffuser plate known as the Mirror Attenuator Mosaic (MAM). The ICM calibration results are instrumental in determining the changes in CERES sensors’ gains after launch from the prelaunch determined values and the on-orbit gain variations. In addition to the broadband response changes derived from the on-board blackbody and the tungsten lamp, the shortwave and the total sensors show a spectrally dependent drop in responsivity in the shorter wavelegth region below one micron that were brought to light through validation studies. The spectrally dependent changes were attributed to the instrument operational modes and the corrections were derived using the sensor radiance comparisons. This paper covers the on-orbit behavior of CERES sensors aboard the Terra and Aqua spacecraft and the determination of the sensor response changes utilising the in-flight calibration and the radiance measurement comparisons viewing various targets. The corrections for the sensor response changes were incorporated in the radiance calculations of CERES Edition3 data products.
Susan Thomas - One of the best experts on this subject based on the ideXlab platform.
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radiometric calibration and performance trends of the clouds and earth s Radiant Energy system ceres instrument sensors onboard the terra and aqua spacecraft
Sensors Systems and Next-Generation Satellites XIX, 2015Co-Authors: M Shankar, Kory J. Priestley, Susan Thomas, Nitchie Smith, Nathaniel P Smith, Dale R WalikainenAbstract:The Clouds and Earth’s Radiant Energy System (CERES) instruments help to study the impact of clouds on the earth's radiation budget. There are currently five instruments- two each on board Aqua and Terra spacecraft and one on the Suomi NPP spacecraft to measure the earth’s reflected shortwave and emitted longwave Energy, which represent two components of the earth’s radiation Energy budget. Flight Models (FM) 1 and 2 are on Terra, FM 3 and 4 are on Aqua, and FM5 is on Suomi NPP. The measurements are made by three sensors on each instrument: a shortwave sensor that measures the 0.3-5 microns wavelength band, a window sensor that measures the water vapor window between 8-12 microns, and a total sensor that measures all incident Energy (0.3- >100 microns). The required accuracy of CERES measurements of 0.5% in the longwave and 1% in the shortwave is achieved through an extensive pre-launch ground calibration campaign as well as on-orbit calibration and validation activities. Onorbit calibration is carried out using the Internal Calibration Module (ICM) that consists of a tungsten lamp, blackbodies, and a solar diffuser known as the Mirror Attenuator Mosaic (MAM). The ICM calibration provides information about the stability of the sensors’ broadband radiometric gains on-orbit. Several validation studies are conducted in order to monitor the behavior of the instruments in various spectral bands. The CERES Edition-4 data products for the FM1-FM4 instruments incorporate the latest calibration methodologies to improve on the Edition-3 data products. In this paper, we discuss the updated calibration methodology and present some validation studies to demonstrate the improvement in the trends using the CERES Edition-4 data products for all four instruments.
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assessment of the clouds and the earth s Radiant Energy system ceres instrument performance and stability on the aqua terra and s npp spacecraft
Proceedings of SPIE, 2015Co-Authors: Nathaniel P Smith, N M Smith, Susan Thomas, Phillip C Hess, Robert S Wilson, Dale R Walikainen, M Shankar, Kory J. PriestleyAbstract:The Clouds and the Earth’s Radiant Energy System (CERES) scanning radiometer is designed to measure reflected solar radiation and thermal radiation emitted by the Earth. Five CERES instruments are currently taking active measurements in-orbit with two aboard the Terra spacecraft (FM1 and FM2), two aboard the Aqua spacecraft (FM3 and FM4), and one aboard the S-NPP spacecraft (FM5). The CERES instrument uses three scanning thermistor bolometers to make broadband radiance measurements in the shortwave (0.3 – 5.0 micrometers), total (0.3 - >100 micrometers) and water vapor window (8 – 12 micrometer) regions. An internal calibration module (ICM) used for in-flight calibration is built into the CERES instrument package consisting of an anodized aluminum blackbody source for calibrating the total and window sensors, and a shortwave internal calibration source (SWICS) for the shortwave sensor. The ICM sources, along with a solar diffusor called the Mirror Attenuator Mosaic (MAM), are used to define shifts or drifts in the sensor response over the life of the mission. In addition, validation studies are conducted to understand any spectral changes that may occur with the sensors and assess the pointing accuracy of the instrument, allowing for corrections to be made to the radiance calculations in CERES data products. This paper covers the observed trends in the internal and solar calibration data, discusses the latest techniques used to correct for sensor response, and explains the validation studies used to assess the performance and stability of the instrument.
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on orbit stability and performance of the clouds and earth s Radiant Energy system ceres instrument sensors onboard the aqua and terra spacecraft
Proceedings of SPIE, 2014Co-Authors: M Shankar, Kory J. Priestley, Susan Thomas, Nitchie Smith, Dale R WalikainenAbstract:The Clouds and Earth’s Radiant Energy System (CERES) instruments onboard the Terra and Aqua spacecraft are part of the NASA Earth Observing System (EOS) constellation to make long-term observations of the earth. CERES measures the earth-reflected shortwave Energy as well as the earth-emitted thermal Energy, which are two components of the earth’s radiation Energy budget. These measurements are made by five instruments- Flight Models (FM) 1 and 2 onboard Terra, FMs 3 and 4 onboard Aqua and FM5 onboard Suomi NPP. Each instrument comprises three sensors that measure the radiances in different wavelength bands- a shortwave sensor that measures in the 0.3 to 5 micron band, a total sensor that measures all the incident Energy (0.3-200 microns) and a window sensor that measures the water-vapor window region of 8 to 12 microns. The stability of the sensors is monitored through on-orbit calibration and validation activities. On-orbit calibration is carried out using the Internal Calibration Module (ICM) that consists of a tungsten lamp, blackbodies, and a solar diffuser known as the Mirror Attenuator Mosaic (MAM). The ICM calibration provides information about the stability of the sensors’ broadband radiometric gains on-orbit. Several validation studies are conducted in order to monitor the behavior of the instruments in various spectral bands. The CERES Edition-4 data products for FM1-FM4 incorporate the latest corrections to the sensor responses using the calibration techniques. In this paper, we present the on-orbit performance stability as well as some validation studies used in deriving the CERES Edition-4 data products from all four instruments.
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performance assessment of the clouds and the earth s Radiant Energy system ceres instruments aboard terra and aqua spacecraft
Proceedings of SPIE, 2013Co-Authors: Susan Thomas, Norman G Loeb, N M Smith, Kory J. Priestley, Phillip C Hess, Robert S Wilson, Dale R Walikainen, M Shankar, Nitchie SmithAbstract:Clouds and the Earth's Radiant Energy System (CERES) instruments were designed to measure the reflected shortwave and emitted longwave radiances of the Earth’s radiation budget and to investigate the cloud interactions with global radiances for the long-term monitoring of Earth's climate. The three scanning thermistor bolometer sensors on CERES measure broadband radiances in the shortwave (0.3 to 5.0 micrometer), total (0.3 to A rigorous and comprehensive radiometric calibration and validation protocol comprising of various studies was developed to evaluate the calibration accuracy of the CERES instruments. The in-flight calibration of CERES sensors are carried out using the internal calibration module (ICM) comprising of blackbody sources and quartzhalogen tungsten lamp, and a solar diffuser plate known as the Mirror Attenuator Mosaic (MAM). The ICM calibration results are instrumental in determining the changes in CERES sensors’ gains after launch from the prelaunch determined values and the on-orbit gain variations. In addition to the broadband response changes derived from the on-board blackbody and the tungsten lamp, the shortwave and the total sensors show a spectrally dependent drop in responsivity in the shorter wavelegth region below one micron that were brought to light through validation studies. The spectrally dependent changes were attributed to the instrument operational modes and the corrections were derived using the sensor radiance comparisons. This paper covers the on-orbit behavior of CERES sensors aboard the Terra and Aqua spacecraft and the determination of the sensor response changes utilising the in-flight calibration and the radiance measurement comparisons viewing various targets. The corrections for the sensor response changes were incorporated in the radiance calculations of CERES Edition3 data products.
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performance stability of the clouds and earth s Radiant Energy system ceres instrument sensors on board the aqua and terra spacecraft
Proceedings of SPIE, 2012Co-Authors: M Shankar, Kory J. Priestley, Susan Thomas, Phillip C Hess, Dale R WalikainenAbstract:The Clouds and Earth’s Radiant Energy System (CERES) instruments measure the earth-reflected shortwave Energy as well as the earth-emitted thermal Energy, which are two components of the earth’s Energy budget. These measurements are made through four instruments on two spacecraft as part of the Earth Observing System (EOS) mission - Flight Models 1 and 2 onboard the Terra spacecraft, and Flight Models 3 and 4 onboard the Aqua spacecraft. Each instrument comprises of three sensors that measure the radiances in different spectral regions- a shortwave channel that measures Energy in the 0.3 to 5 micron wavelength band, a total channel that measures all the incident Energy (0.3- <100 microns) and a window channel that measures the water-vapor window region of 8 to 12 microns. The required accuracy of the CERES sensors is achieved through pre-launch ground-based calibrations as well as on-orbit calibration activities. Onorbit calibration is carried out using the Internal Calibration Module (ICM) that consists of a quartz-halogen tungsten lamp, blackbodies, and a solar diffuser plate known as the Mirror Attenuator Mosaic (MAM). The ICM calibration provides information about the change in the CERES sensors’ broadband radiometric gains on-orbit from the pre-launch values. Several validation studies are conducted in order to monitor the behavior of the instruments in various spectral bands. The CERES Edition-3 data products incorporate the latest upgrades to the calibration techniques. In this paper, we present the on-orbit performance stability as well as some validation studies using the CERES Edition-3 data products from all four instruments.
Bruce A Wielicki - One of the best experts on this subject based on the ideXlab platform.
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clouds and earth Radiant Energy system ceres a review past present and future
Advances in Space Research, 2011Co-Authors: G.l. Smith, Bruce A Wielicki, David R Doelling, Norman G Loeb, Patrick Minnis, Kory J. Priestley, Thomas P Charlock, David A RutanAbstract:The Clouds and Earth Radiant Energy System (CERES) project s objectives are to measure the reflected solar radiance (shortwave) and Earth-emitted (longwave) radiances and from these measurements to compute the shortwave and longwave radiation fluxes at the top of the atmosphere (TOA) and the surface and radiation divergence within the atmosphere. The fluxes at TOA are to be retrieved to an accuracy of 2%. Improved bidirectional reflectance distribution functions (BRDFs) have been developed to compute the fluxes at TOA from the measured radiances with errors reduced from ERBE by a factor of two or more. Instruments aboard the Terra and Aqua spacecraft provide sampling at four local times. In order to further reduce temporal sampling errors, data are used from the geostationary meteorological satellites to account for changes of scenes between observations by the CERES radiometers. A validation protocol including in-flight calibrations and comparisons of measurements has reduced the instrument errors to less than 1%. The data are processed through three editions. The first edition provides a timely flow of data to investigators and the third edition provides data products as accurate as possible with resources available. A suite of cloud properties retrieved from the MODerate-resolution Imaging Spectroradiometer (MODIS) by the CERES team is used to identify the cloud properties for each pixel in order to select the BRDF for each pixel so as to compute radiation fluxes from radiances. Also, the cloud information is used to compute radiation at the surface and through the atmosphere and to facilitate study of the relationship between clouds and the radiation budget. The data products from CERES include, in addition to the reflected solar radiation and Earth emitted radiation fluxes at TOA, the upward and downward shortwave and longwave radiation fluxes at the surface and at various levels in the atmosphere. Also at the surface the photosynthetically active radiation and ultraviolet radiation (total, UVA and UVB) are computed. The CERES instruments aboard the Terra and Aqua spacecraft have served well past their design life times. A CERES instrument has been integrated onto the NPP platform and is ready for launch in 2011. Another CERES instrument is being built for launch in 2014, and plans are being made for a series of follow-on missions.
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coloration determination of spectral darkening occurring on a broadband earth observing radiometer application to clouds and the earth s Radiant Energy system ceres
Proceedings of SPIE, 2006Co-Authors: Grant Matthews, Konstantin Loukachine, Norman G Loeb, Kory J. Priestley, Susan Thomas, Dale R Walikainen, Bruce A WielickiAbstract:It is estimated that in order to best detect real changes in the Earth's climate system, space based instrumentation measuring the Earth Radiation Budget (ERB) must remain calibrated with a stability of 0.3% per decade. Such stability is beyond the specified accuracy of existing ERB programs such as the Clouds and the Earth's Radiant Energy System (CERES, using three broadband radiometric scanning channels: the shortwave 0.3 - 5μm, total 0.3- > 100μm, and window 8 - 12μm). It has been shown that when in low earth orbit, optical response to blue/UV radiance can be reduced significantly due to UV hardened contaminants deposited on the surface of the optics. Since typical onboard calibration lamps do not emit sufficient Energy in the blue/UV region, this darkening is not directly measurable using standard internal calibration techniques. This paper describes a study using a model of contaminant deposition and darkening, in conjunction with in-flight vicarious calibration techniques, to derive the spectral shape of darkening to which a broadband instrument is subjected. Ultimately the model uses the reflectivity of Deep Convective Clouds as a stability metric. The results of the model when applied to the CERES instruments on board the EOS Terra satellite are shown. Given comprehensive validation of the model, these results will allow the CERES spectral responses to be updated accordingly prior to any forthcoming data release in an attempt to reach the optimum stability target that the climate community requires.
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angular distribution models for top of atmosphere radiative flux estimation from the clouds and the earth s Radiant Energy system instrument on the tropical rainfall measuring mission satellite part ii validation
Journal of Applied Meteorology, 2003Co-Authors: Norman G Loeb, Bruce A Wielicki, Natividad Manalosmith, Konstantin Loukachine, David F. YoungAbstract:Clouds and the Earth’s Radiant Energy System (CERES) investigates the critical role that clouds and aerosols play in modulating the radiative Energy flow within the Earth‐atmosphere system. CERES builds upon the foundation laid by previous missions, such as the Earth Radiation Budget Experiment, to provide highly accurate top-of-atmosphere (TOA) radiative fluxes together with coincident cloud and aerosol properties inferred from high-resolution imager measurements. This paper describes the method used to construct empirical angular distribution models (ADMs) for estimating shortwave, longwave, and window TOA radiative fluxes from CERES radiance measurements on board the Tropical Rainfall Measuring Mission satellite. To construct the ADMs, multiangle CERES measurements are combined with coincident high-resolution Visible Infrared Scanner measurements and meteorological parameters from the European Centre for Medium-Range Weather Forecasts data assimilation product. The ADMs are stratified by scene types defined by parameters that have a strong influence on the angular dependence of Earth’s radiation field at the TOA. Examples of how the new CERES ADMs depend upon the imager-based parameters are provided together with comparisons with existing models.
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angular distribution models for top of atmosphere radiative flux estimation from the clouds and the earth s Radiant Energy system instrument on the tropical rainfall measuring mission satellite part ii validation
Journal of Applied Meteorology, 2003Co-Authors: Norman G Loeb, Bruce A Wielicki, Natividad Manalosmith, Konstantin Loukachine, David F. YoungAbstract:Abstract Top-of-atmosphere (TOA) radiative fluxes from the Clouds and the Earth's Radiant Energy System (CERES) are estimated from empirical angular distribution models (ADMs) that convert instantaneous radiance measurements to TOA fluxes. This paper evaluates the accuracy of CERES TOA fluxes obtained from a new set of ADMs developed for the CERES instrument onboard the Tropical Rainfall Measuring Mission (TRMM). The uncertainty in regional monthly mean reflected shortwave (SW) and emitted longwave (LW) TOA fluxes is less than 0.5 W m−2, based on comparisons with TOA fluxes evaluated by direct integration of the measured radiances. When stratified by viewing geometry, TOA fluxes from different angles are consistent to within 2% in the SW and 0.7% (or 2 W m−2) in the LW. In contrast, TOA fluxes based on ADMs from the Earth Radiation Budget Experiment (ERBE) applied to the same CERES radiance measurements show a 10% relative increase with viewing zenith angle in the SW and a 3.5% (9 W m−2) decrease with vie...
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determination of unfiltered radiances from the clouds and the earth s Radiant Energy system instrument
Journal of Applied Meteorology, 2001Co-Authors: Norman G Loeb, Bruce A Wielicki, Kory J. Priestley, David P Kratz, Erika Geier, Richard N Green, Patricia Orawe Hinton, Sandra K NolanAbstract:A new method for determining unfiltered shortwave (SW), longwave (LW) and window (W) radiances from filtered radiances measured by the Clouds and the Earth's Radiant Energy System (CERES) satellite instrument is presented. The method uses theoretically derived regression coefficients between filtered and unfiltered radiances that are a function of viewing geometry, geotype and whether or not cloud is present. Relative errors in insta.ntaneous unfiltered radiances from this method are generally well below 1% for SW radiances (approx. 0.4% 1(sigma) or approx.l W/sq m equivalent flux), < 0.2% for LW radiances (approx. 0.1% 1(sigma) or approx.0.3 W/sq m equivalent flux) and < 0.2% (approx. 0.1% 1(sigma) for window channel radiances.
Seiji Kato - One of the best experts on this subject based on the ideXlab platform.
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uncertainty in net surface heat flux due to differences in commonly used albedo products
Journal of Climate, 2020Co-Authors: Allison Hogikyan, Meghan F Cronin, Dongxiao Zhang, Seiji KatoAbstract:AbstractThe ocean surface albedo is responsible for the distribution of solar (shortwave) Radiant Energy between the atmosphere and ocean and therefore is a key parameter in Earth’s surface Energy ...
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surface irradiances of edition 4 0 clouds and the earth s Radiant Energy system ceres Energy balanced and filled ebaf data product
Journal of Climate, 2018Co-Authors: Seiji Kato, David R Doelling, Norman G Loeb, Fred G Rose, David A Rutan, Tyler J Thorsen, Xianglei Huang, William L Smith, Wenying SuAbstract:AbstractThe algorithm to produce the Clouds and the Earth’s Radiant Energy System (CERES) Edition 4.0 (Ed4) Energy Balanced and Filled (EBAF)-surface data product is explained. The algorithm forces...
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clouds and the earth s Radiant Energy system ceres Energy balanced and filled ebaf top of atmosphere toa edition 4 0 data product
Journal of Climate, 2018Co-Authors: Norman G Loeb, David R Doelling, Fred G Rose, Wenying Su, Joseph G Corbett, Hailan Wang, Cathy Nguyen, Lusheng Liang, Cristian Mitrescu, Seiji KatoAbstract:AbstractThe Clouds and the Earth’s Radiant Energy System (CERES) Energy Balanced and Filled (EBAF) top-of-atmosphere (TOA), Edition 4.0 (Ed4.0), data product is described. EBAF Ed4.0 is an update to EBAF Ed2.8, incorporating all of the Ed4.0 suite of CERES data product algorithm improvements and consistent input datasets throughout the record. A one-time adjustment to shortwave (SW) and longwave (LW) TOA fluxes is made to ensure that global mean net TOA flux for July 2005–June 2015 is consistent with the in situ value of 0.71 W m−2. While global mean all-sky TOA flux differences between Ed4.0 and Ed2.8 are within 0.5 W m−2, appreciable SW regional differences occur over marine stratocumulus and snow/sea ice regions. Marked regional differences in SW clear-sky TOA flux occur in polar regions and dust areas over ocean. Clear-sky LW TOA fluxes in EBAF Ed4.0 exceed Ed2.8 in regions of persistent high cloud cover. Owing to substantial differences in global mean clear-sky TOA fluxes, the net cloud radiative eff...
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arctic radiation icebridge sea and ice experiment the arctic Radiant Energy system during the critical seasonal ice transition
Bulletin of the American Meteorological Society, 2017Co-Authors: William L Smith, Christy Hansen, Anthony Bucholtz, B E Anderson, Matthew Beckley, Joseph G Corbett, Richard I Cullather, Keith M Hines, M A Hofton, Seiji KatoAbstract:AbstractThe National Aeronautics and Space Administration (NASA)’s Arctic Radiation-IceBridge Sea and Ice Experiment (ARISE) acquired unique aircraft data on atmospheric radiation and sea ice properties during the critical late summer to autumn sea ice minimum and commencement of refreezing. The C-130 aircraft flew 15 missions over the Beaufort Sea between 4 and 24 September 2014. ARISE deployed a shortwave and longwave broadband radiometer (BBR) system from the Naval Research Laboratory; a Solar Spectral Flux Radiometer (SSFR) from the University of Colorado Boulder; the Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) from the NASA Ames Research Center; cloud microprobes from the NASA Langley Research Center; and the Land, Vegetation and Ice Sensor (LVIS) laser altimeter system from the NASA Goddard Space Flight Center. These instruments sampled the Radiant Energy exchange between clouds and a variety of sea ice scenarios, including prior to and after refreezing began. The most c...
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cloud radiative forcing at the atmospheric radiation measurement program climate research facility 2 vertical redistribution of Radiant Energy by clouds
Journal of Geophysical Research, 2006Co-Authors: Gerald G Mace, Sally Benson, Seiji KatoAbstract:Documentation of the effects of clouds on the Radiant Energy balance of the surface and atmosphere represents a shortcoming in the set of observations that are needed to ascertain the validity of climate model simulations. While clouds are known to cool the climate system from top of atmosphere (TOA) radiation budget studies, the redistribution of Energy between the surface and atmosphere and within the atmosphere by clouds has not been examined in detail with observations. Using data collected at the Atmospheric Radiation Measurement Program (ARM) Southern Great Plains (SGP) site, we use measurements of cloud occurrence and structure together with a scheme to characterize the cloud microphysical and radiative properties to estimate the uncertainty in our ability to calculate the radiative forcing and effect of clouds at the top of atmosphere, the surface and within the atmosphere. We find that overcast clouds during 2000 tended to have a small net influence on the atmosphere (6 W m -2 ± 3 W m -2 of heating) with net TOA and surface cooling (25 W m -2 ± 3 W m -2 and 32 ± 3 W m -2 , respectively). These statistics mask a significant redistribution of Radiant Energy within the atmosphere by clouds where low overcast clouds resulted in strong atmospheric cooling (37 W m -2 ± 9 W m -2 ), and thin high clouds resulted in warming (21 W m -2 ± 6 W m -2 ) suggesting that accurate prediction of the phasing of these cloud types within meteorological features is important for capturing the essential feedbacks by clouds to the general circulation.
