Evaluating Surface Measured vs. Satellite-Retrieved Long-term Surface SW fluxes by Surface Climatological Type.
Abstract
This study compares an analysis of monthly average surface shortwave (SW) radiation measurements from 1983 through 1995 to SW fluxes from the newly released NASA/GEWEX Surface Radiation Budget Project (SRB). The NASA/GEWEX SRB dataset provides a twelve-year-plus (July 1983 to October 1995) global dataset of surface shortwave (SW) and longwave (LW) radiative parameters on a 1°x1° grid. The SW fluxes were computed with two algorithms: a primary algorithm (modified version of Pinker and Laszlo, 1992) and a SW quality-check algorithm (modified version of Darnell et al., 1992). Cloud properties were derived on a 1°-resolution using International Satellite Cloud Climatology Project (ISCCP) pixel-level (DX) datasets. Other meteorological inputs, namely the temperature and humidity profiles, were taken from the GEOS-1 reanalysis product of the Global Modeling and Assimilation Office at NASA/GSFC. Ozone data were obtained from TOMS archives. Daily and monthly surface measurements were obtained from the World Radiation Data Center in St. Petersburg, Russia. Sites of high quality containing a continuous long-time series were selected and were clustered in areas of similar climatological surface type as proposed by Smith et al. (2002, J. Clim). Long-term estimates of the fluxes as inferred by the SRB dataset were compared to flux measurements. Comparisons were made in regards to the seasonal and interannual variability within the region as compared to the variability estimated by the SW SRB. In general, most regions showed high correlation between the estimates and the measurements. A few regions showed long-term changes consistent with a downward trend. One exception was a region in Egypt where surface measurements showed downward change over most the time period that was not captured in the SRB record. The reasons for this are explored. Lastly, long-term changes over the 12 year period are computed on a 1 degree basis.
- Publication:
-
AGU Spring Meeting Abstracts
- Pub Date:
- May 2004
- Bibcode:
- 2004AGUSM.A21A..07C
- Keywords:
-
- 3359 Radiative processes