||Monitoring ice sheet mass variations from GRACE
We use 22 monthly GRACE gravity fields to estimate the linear trends in Greenland and Antarctic ice mass during 2002-2004. We also estimate net snow accumulation from the nonsecular component of the GRACE signal. For Greenland, for example, we recover a decrease in total ice mass of $75 \pm 26 \ km^3/yr$, consistent with estimates from other techniques. Our uncertainty estimates for both Greenland and Antarctica are dominated by the effects of GRACE measurement errors and errors in our post glacial rebound correction.