This post is a follow-on to both GaryJ’s comments on this morning’s LIS snow water equivalent (SWE) post, and to the post on MODIS snow cover mapping. I went ahead and produced a LIS SWE graphic at 1900 UTC 31 JAN 2010, approximately coincident to the time of the MODIS false color snow map (1919 UTC) and geographical area.
The image below shows the output from the 3-km SPoRT LIS that could be used to help quantify the actual water content of the snow cover. Compared to the MODIS false color image in the previous post, it appears that the LIS-Noah SWE coverage may be slightly overdone on the southern edge of the swath from Arkansas to Georgia. This is probably due to the fact that the Noah land surface model running within LIS adds to the SWE field anytime the land surface temperature is below freezing. Therefore, areas of mixed precipitation or freezing rain also lead to an accumulation of the SWE field.
A unique product that may be worth considering is to supplement the MODIS snow mask with quantitative information from LIS within the mask indicated by MODIS. Another option may be to assimilate AMSR-E SWE information to help adjust the LIS SWE field towards the satellite observations.