clarify MAR units and variables

[aaarendt]

• what is the difference between DZSN1 and ROSN1 to compute snow water equivalent? Both are of dimension (TIME, SNOLAY, Y11_190, X11_210). We used the product of the two and integrated over SNOLAY to compute SWE. But the result increases monotonically over the course of a year and reset on Jan 1 of the next year.
• Varaibles like SMB have values for both the proportion of the a grid box covered by ice and the proportion not covered by ice. How are the ice cover fraction of the grid (MSK) factored in these sector values? For example, if I intend to check the contribution of different processes to SMB, how should I use the ice cover fraction MSK?

SMB~SF+RF-RU-SU-SW

Here SMB, RU, SU has values for two sectors, but SF and RF has only values for the whole grid and SW has only values for sector 1.

Does it mean:

SMB(sector1) = SF*MSK/100 + RF*MSK/100 - RU(sector1) - SU(sector1) - SW(sector1) and SMB(sector2) = SF*(1-MSK/100) + RF*(1-MSK/100) - RU(sector2) - SU(sector2)

• the time integrated SMB(sector1) has a seasonal variability that is out of phase with GRACE