Validation of the CERES Edition 2B Surface-Only Flux AlgorithmsSource: Journal of Applied Meteorology and Climatology:;2010:;volume( 049 ):;issue: 001::page 164DOI: 10.1175/2009JAMC2246.1Publisher: American Meteorological Society
Abstract: The Clouds and the Earth?s Radiant Energy System (CERES) project uses two shortwave (SW) and two longwave (LW) algorithms to derive surface radiative fluxes on an instantaneous footprint basis from a combination of top-of-atmosphere fluxes, ancillary meteorological data, and retrieved cloud properties. Since the CERES project examines the radiative forcings and feedbacks for Earth?s entire climate system, validation of these models for a wide variety of surface conditions is paramount. The present validation effort focuses upon the ability of these surface-only flux algorithms to produce accurate CERES Edition 2B single scanner footprint data from the Terra and Aqua spacecraft measurements. To facilitate the validation process, high-quality radiometric surface observations have been acquired that were coincident with the CERES-derived surface fluxes. For both SW models, systematic errors range from ?20 to ?12 W m?2 (from ?2.8% to ?1.6%) for global clear-sky cases, while for the all-sky SW model, the systematic errors range from 14 to 21 W m?2 (3.2%?4.8%) for global cloudy-sky cases. Larger systematic errors were seen for the individual surface types, and significant random errors where observed, especially for cloudy-sky cases. While the SW models nearly achieved the 20 W m?2 accuracy requirements established for climate research, further improvements are warranted. For the clear-sky LW model, systematic errors were observed to fall within ±5.4 W m?2 (±1.9%) except for the polar case in which systematic errors on the order from ?15 to ?11 W m?2 (from ?13% to ?7.2%) occurred. For the all-sky LW model, systematic errors were less than ±9.2 W m?2 (±7.6%) for both the clear-sky and cloudy-sky cases. The random errors were less than 17 W m?2 (6.2%) for clear-sky cases and 28 W m?2 (13%) for cloudy-sky cases, except for the desert cases in which very high surface skin temperatures caused an overestimation in the model-calculated surface fluxes. Overall, however, the LW models met the accuracy requirements for climate research.
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contributor author | Kratz, David P. | |
contributor author | Gupta, Shashi K. | |
contributor author | Wilber, Anne C. | |
contributor author | Sothcott, Victor E. | |
date accessioned | 2017-06-09T16:27:56Z | |
date available | 2017-06-09T16:27:56Z | |
date copyright | 2010/01/01 | |
date issued | 2010 | |
identifier issn | 1558-8424 | |
identifier other | ams-68358.pdf | |
identifier uri | http://onlinelibrary.yabesh.ir/handle/yetl/4209907 | |
description abstract | The Clouds and the Earth?s Radiant Energy System (CERES) project uses two shortwave (SW) and two longwave (LW) algorithms to derive surface radiative fluxes on an instantaneous footprint basis from a combination of top-of-atmosphere fluxes, ancillary meteorological data, and retrieved cloud properties. Since the CERES project examines the radiative forcings and feedbacks for Earth?s entire climate system, validation of these models for a wide variety of surface conditions is paramount. The present validation effort focuses upon the ability of these surface-only flux algorithms to produce accurate CERES Edition 2B single scanner footprint data from the Terra and Aqua spacecraft measurements. To facilitate the validation process, high-quality radiometric surface observations have been acquired that were coincident with the CERES-derived surface fluxes. For both SW models, systematic errors range from ?20 to ?12 W m?2 (from ?2.8% to ?1.6%) for global clear-sky cases, while for the all-sky SW model, the systematic errors range from 14 to 21 W m?2 (3.2%?4.8%) for global cloudy-sky cases. Larger systematic errors were seen for the individual surface types, and significant random errors where observed, especially for cloudy-sky cases. While the SW models nearly achieved the 20 W m?2 accuracy requirements established for climate research, further improvements are warranted. For the clear-sky LW model, systematic errors were observed to fall within ±5.4 W m?2 (±1.9%) except for the polar case in which systematic errors on the order from ?15 to ?11 W m?2 (from ?13% to ?7.2%) occurred. For the all-sky LW model, systematic errors were less than ±9.2 W m?2 (±7.6%) for both the clear-sky and cloudy-sky cases. The random errors were less than 17 W m?2 (6.2%) for clear-sky cases and 28 W m?2 (13%) for cloudy-sky cases, except for the desert cases in which very high surface skin temperatures caused an overestimation in the model-calculated surface fluxes. Overall, however, the LW models met the accuracy requirements for climate research. | |
publisher | American Meteorological Society | |
title | Validation of the CERES Edition 2B Surface-Only Flux Algorithms | |
type | Journal Paper | |
journal volume | 49 | |
journal issue | 1 | |
journal title | Journal of Applied Meteorology and Climatology | |
identifier doi | 10.1175/2009JAMC2246.1 | |
journal fristpage | 164 | |
journal lastpage | 180 | |
tree | Journal of Applied Meteorology and Climatology:;2010:;volume( 049 ):;issue: 001 | |
contenttype | Fulltext |