MEAN WIND PATTERNS AND SNOW DEPTHS IN AN ALPINE-SUB-ALPINE ECOSYSTEM AS MEASURED BY DAMAGE TO CONIFEROUS TREES

1. Deformations of Engelmann spruce and subalpine fir trees were surve yed for the purpose of determining climatic wind speeds and directions and snow depths in the Glacier Lakes Ecosystem Experiments Site (GLEE S) in the Snowy Range of southeastern Wyoming, USA. Tree deformations were recorded at 50- and 100-m grid intervals over areas of c. 30 ha a nd 300 ha, respectively, over the GLEES.2. The climatic mean wind spee d was estimated to be 7.4 m s(-1); the mean air flow was predominantly westerly. The snow depths ranged from less than 0.2 m to 5.5 m, depen ding on topographic features and vegetative architecture. 3. Compared with snow depth surveys, precipitation measurements, and a degree-day snow depth model, the average snow depth estimated by the tree deforma tion method was 70% of the long-term mean. 4. The tree deformation met hod was useful for detailed estimates of wind speed, wind direction, a nd snow depth at a fine scale in complex terrain where meteorological instrumentation and snow survey data are minimal.