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The longwave flux is defined as 5 to 100 microns. It is obtained from the total channel filtered radiance minus the shortwave channel filtered radiance during the day. The shortwave channel is assumed to have negligible energy during the night, so the total channel filtered radiance is used for the ...

The received shortwave energy at night is assumed to be 0. Therefore, the longwave is just from the total channel. Since there should be minimum energy in the 0 to 5 microns area being emitted or reflected by the Earth at night, the day and night values are comparable. The longwave range is consider...

Yes, I understand the large amount of data need for running a radiative transfer model. The CERES project runs the Fu-Liou RTM for several products, CRS, CRS1deg-Hour, SYN1deg-1Hour, SYN1deg-MHour, SYN1deg-Day, and SYN1deg-Month. The CRS is a SSF based product where the others are gridded products. ...

The MODIS Land Aerosols Cloud Fraction is there to assist the user and interpreting the MODIS aerosol optical thickness. Since the MODIS aerosol team uses a different cloud mask than the CERES project. They use a 10 by 10 MODIS pixel grouping and determine the cloud fraction within it. There are mul...

The 0.65 optical depth and the 3.7 particle radius and water path are consistent. These are the values generally used in radiative transfer model calculation. Looking at clouds at different wavelengths provide additional information about the cloud properties and are useful in doing spectral band ra...

The five GEO satellites used to process a given month have to have the same version to make an internal product used for SYN1deg. After processing Himawari 8 data for about three years, a problem was discovered that required reprocessing back to July 2015 when Himawari 8 started to be processed. The...

There is a limitation in our processing code that requires that all five geostationary satellite have the same version. We needed to reprocess data for the Himawari 8 starting in July 2015 that necessitated the change. The overlap period was what was processed before the need was discovered. We are ...

The CERES instruments scans the Earth with a view zenith angle varying from 0 to 65 degrees on each side of the satellite when in cross track mode. There are about 86 footprints on the SSF per scan with separation growing with view zenith angle. The footprints are about 8 km apart at nadir and growi...

The cloud effective height and pressure are values that is obtained strictly from the infrared radiance obtained by the imager. A certain amount of water droplets are needed before the infrared signal becomes strong enough to be detected by a passive instrument such as MODIS or VIIRS. This can be lo...

The second statement is correct, "A phase of 1 indicates all cloud pixels are liquid while a phase of 2 means ice. A phase of 1.5 is a cloud region where half of the MODIS pixels are ice and the other half are liquid." The cloud phase is calculated as below in CERES processing: Cloud Parti...