Annual melt duration from Special Sensor Microwave/Imager satellite data is used in a simple surface mass balance (SMB) model to estimate runoff rates, mass balance, and surface elevation changes for the Greenland ice sheet. Estimates are made using a variable accumulation rate that is based on precipitation from a dynamic climate model using European Centre for Medium-Range Weather Forecasts analysis data. The overall SMB is positive for the 1988--1999 period, but it is near the estimate of calving rates. Two years, 1995 and 1998, show a negative SMB. There is some evidence that years with higher runoff are associated with lower accumulation and that years with higher than average runoff in southern Greenland are associated with lower than average runoff in the north. Variations in accumulation rates dominate SMB variability in east and southeast Greenland, while runoff rates dominate in west Greenland. SMB is also used to estimate elevation changes resulting from trends in SMB during the 1988--1999 and 1993--1999 time periods, which in general agree with laser altimeter finding of thinning below 2000 m above sea level and near equilibrium above that elevation.