Tuesday, 11 January 2005: 2:00 PM
Investigation of flows within complex terrain and along coastlines using an airborne Doppler wind lidar: Observations and model comparisons
A unique Doppler Wind Lidar (DWL) has been installed on a Twin Otter aircraft with funding from the Office of Naval Research (ONR) and the Integrated Program Office of the NPOESS. The airborne lidar referred to as TODWL (Twin Otter DWL) was flown during field experiments in 2002 and 2003 off the central California coast and has provided a set of clear air wind profiles of unprecedented accuracy ( RMSE < .05 m/s) and horizontal resolution(< 1 km) over the coastal region of Monterey Bay and the adjacent complex terrain. This presentation will illustrate these TODWL wind observations and how they are able to capture the complex circulations near the coastline. In addition, we will present comparison between the TODWL wind profiles and other existing measurement platforms such as microwave wind profilers and sounders.
Models such as the MM5 are being used to predict flows within complex terrain, over urban areas and along coastlines. While the performance of the models is slowly improving, there are still challenges to validate their analyses and forecasts on the meso gamma scale, and to assimilate data, especially wind data, on the same scale. Comparisons between the 2003 TODWL observations and the MM5 (run by the Naval Postgraduate School) analyses and predictions at the same time will also be presented.