Wednesday, 5 May 2004
High Resolution Observations of Boundary Layer Structures in Isabel at Landfall
Richelieu Room (Deauville Beach Resort)
Three Doppler On Wheels (DOW) mobile radars intercepted the central region of hurricane Isabel as it made landfall near Atlantic, North Carolina. The radars were deployed near Atlantic and Sea Level, North Carolina in a dual-Doppler configuration with a 9 km baseline. The new Rapid-Scan DOW was deployed in the dual-Doppler lobe 800 m from an instrumented tower. The dual-Doppler radars collected data in boundary layer rolls with 12.5 m and 25 m resolution resulting in the highest resolution dual-Doppler to date. The ranges to the instrumented tower were approximately 4 km and 8 km, resulting in beamwidths of 60 m and 120 m. The Rapid-Scan DOW collected volumetric updates every 15 s over the tower.
Analysis has just started, but is expected to focus on the characteristics of the boundary layer rolls / wind streaks, and their evolution, which can be documented due to the high spatial and temporal scales of the DOW and Rapid-DOW observations. Dual- and Single-Doppler analysis may be compared to time series of winds measured at 15 m by the TTU instrumented tower.