A 22-Year Global Shortwave and Longwave Radiation Dataset from the NASA/GEWEX SRB Project: Overview and Analysis
Abstract
Quantifying the interaction of solar (or shortwave) and terrestrial (or longwave) radiation with the Earth's surface is of vital importance in understanding the global climate system. The NASA/GEWEX (Global Energy and Water cycle Experiment) SRB (Surface Radiation Budget) project provides estimates of surface shortwave and longwave fluxes on a 1 degree by 1 degree grid system for the period from July, 1983 to June, 2005. Input information comes from satellite and assimilation products. Water vapor and temperature profiles are from the Goddard Earth Observing System V 4.0.3 (GEOS-4) long-term meteorological assimilation. Surface and cloud radiances and cloud retrievals are computed from the International Satellite Cloud Climatology Project Pixel- Level (ISCCP-DX) data. Column ozone is computed from the Total Ozone Mapping Spectrometer (TOMS) and TIROS Operational Vertical Sounder (TOVS). The flux data sets are derived from primary algorithms that provide a more explicit treatment of the atmospheric and surface properties and secondary algorithms that contain parameterization for these processes. Estimates of the Top of Atmosphere (TOA) fluxes are provided with the primary algorithms. This data set is a major contributor to the GEWEX Radiative Flux Assessment (RFA) activity. This presentation provides an overview of the latest version (V 2.7) by first presenting the results of an extensive validation analysis using surface flux measurements from the Baseline Surface Radiation Network (BSRN), the World Radiation Data Center (WRDC), the Global Energy Balance Archive (GEBA), and the Atmospheric Radiation Measurement (ARM) networks. The validation analysis is used to infer the uncertainties of these quantities compared against data from ground-based sites. Comparisons for SRB flux quantities are shown relative to other data sets such as the ISCCP Flux Data (ISCCP-FD), Clouds and the Earth's Radiant Energy System (CERES), Forty-year European Re-Analysis (ERA-40) and National Centers for Environmental Prediction (NCEP). We present the global annual means and zonal annual cycle of the flux components including inferred cloud radiative forcing. The time series at TOA and surface for global, land, ocean, and tropical areas are presented and analyzed for variability and consistency with other long-term data sets such as ISCCP-FD. Finally, the results are summarized in such a way as to characterize the largest uncertainties of the data set and the future work planned to address the deficiencies.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2006
- Bibcode:
- 2006AGUFM.A51G..03Z
- Keywords:
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- 0321 Cloud/radiation interaction;
- 0360 Radiation: transmission and scattering;
- 1616 Climate variability (1635;
- 3305;
- 3309;
- 4215;
- 4513);
- 1637 Regional climate change;
- 1640 Remote sensing (1855)