Changes in the Greenland ice sheet are considered important indicators of global climate change. These changes can be monitored using space-borne scatterometers which provide frequent coverage of the entire ice sheet. This paper provides a general overview of backscatter measurements over Greenland and the distinguishing attributes of the data sets over the different snow facies including temporal signatures. Seasat-A scatterometer (1978), NSCAT (1996-1997), SeaWinds (1999-present), and ERS AMI (1992-2000) scatterometer data are analyzed to evaluate the long term changes in the ice sheet. An increase in backscatter is observed in the dry snow zone near the dry snow zone/percolation zone boundary. A simple algorithm is applied to determine the length and extent of the melt for the summer of 1999 as observed by SeaWinds and ERS. A comparison between the two sensors shows similar results with the apparent differences attributed to the higher temporal resolution of SeaWinds and the difference in frequencies between the two instruments.