- The CERES dataset is satellite data that is based on radiation measurements made from low earth orbit. The CERES data has two parts. The first part is observational data, measurements of downwelling and upwelling solar radiation and of upwelling longwave radiation. It is usually referred as the CERES “top-of-atmosphere” data. The official name is “CERES EBAF-TOA”, and it is available here.
- However, the second part of the CERES is not top-of-atmosphere observations from the satellite. Instead, it is calculated surface data based on the CERES TOA observations along with other satellite observations. It’s called the “CERES EBAF-Surface” dataset, and is available from the same location.
- As a result, I’ve always been concerned about the accuracy of the CERES surface data. After all, it’s just calculations, it’s not actual observations. So I got to thinking that I could “ground-truth” the CERES surface observations by using the TAO buoy data. It’s not a comprehensive test by any means, but the TAO buoys cover a region of great interest to me, the tropical Pacific. The TAO buoy data is available here.
söndag 22 februari 2015
CERES Satellite vs Surface Buoy Temperatures
The recent discussion on the Big Bluff of DLR gets perspective in a WUWT post by Willis Eschenbach on CERES Calculated Surface Datasets:
Eschenbach is surprised to see that makes CERES and TAO surface temperatures observation agree.
But this is not surprising: To measure surface temperature at distance from satellite is possible, through the atmospheric window at clear sky.
Eschenbach is even more surprised to see agreement on DLR from CERES satellite and TAO surface data.
Again this is no wonder, since DLR is computed in the same (unphysical) way from temperature measurements. By inventive "calculation" anything can be supported.