32nd Conference on Broadcast Meteorology/31st Conference on Radar Meteorology/Fifth Conference on Coastal Atmospheric and Oceanic Prediction and Processes

Tuesday, 12 August 2003: 11:15 AM
Wind Profiler Performance in Complex Terrain: Juneau, Alaska
Stephen A. Cohn, NCAR, Boulder, CO
Poster PDF (1.0 MB)
Four years of data from three radar wind profilers and a network of anemometers are used to examine the flow regimes near Juneau, Alaska. Wind direction probability density functions and wind rose histograms show the dominant wind speeds and directions from a long time series of observations. Analysis of diurnal variation separates mountain-valley flow events from synoptically riven events. Flow constrained by the Gastineau channel dominates the winds near downtown Juneau, and the wind profilers show that this flow rotates and merges with the synoptic flow aloft above the height of the surrounding mountains. Taku direction flows, from the NE over the Taku glacier, are also documented. These flows are less frequent but can cause strong wind storms at the surface. In addition, more local flow effects are seen including winds turning in response to terrain influence, drainage flows in creek valleys, and cross-valley flows. This analysis also demonstrates that radar wind profilers using recently developed data processing algorithms (in this case NIMA/NWCA) can provide valuable data even at low altitudes near complex terrain and sources of ground clutter.

Supplementary URL: