Using GIS to establish relationships between environmental variables and snowdepths in Green Lakes Valley, Colorado, for use in SWE estimations and forecasting

Geographic Infonnation Systems (GIS) may be useful in forecasting the quantity ofwater stored in alpine snowpacks because relationships may be established between environmental characteristics and seasonal snowdepth patterns for watersheds of interest. A snow survey perfonned in May of 1997 for the 224-ha Green Lake 4 Watershed of the Colorado Front Range involved intensive sampling (n = 194) of snowdepth and snow density measurements around the basin. These field data, in conjunction with snow covered area, DEM and landcover data from the Niwot Ridge LTER Spatial Database, were used to investigate 1) the relationship of snowdepth to landcover, 2) the relationship of snowdepth to slope, and 3) the relationship of snowdepth to aspect.