The NCAR 449 MHz Modular Wind Profiler Development Bill Brown, Steve Cohn, Brad Lindseth Terry Hock, Charlie Martin NCAR / EOL Jim Jordan, Dan Law, Warner Ecklund NOAA Also collaborating with other groups (eg, University of Oklahoma)

“Workhorse” systems for many years. Mature stage of life-cycle Today’s technology ready to go higher and faster Three 915 MHz Wind Profilers with RASS Winds to ~3 km, temperature to ~ 1km 30-min time, m height resolution Over 40 deployments since 1992 Advances: MAPR spaced-antenna, Mobile-ISS, Ship operations Legacy 915 MHz Wind Profilers

 A larger network of boundary layer systems Unmet needs based on years of requests Also collaborative opportunities……  Winds to higher altitudes  Better time resolution  Simplified instrument setup and autonomy  A testbed for algorithm/technique development

Example: T-REX

Boundary Layer Config. 3 antenna modules Network of 6 Mid-Tropospheric Config. 7 antenna modules Network of 2 Lower Stratospheric Config. 19 antenna modules 200 m – 7 km m 300 m – 15 km m Range: Resolution: 150 m – 4 km 30 m Not to scale! One module 449 MHz Modular Wind Profiler 449 MHz gives us the range Modularity gives us the flexibility

Modular Profiling Network (with 19 antenna modules available) One station that samples throughout the troposphere Two stations that sample a deeper cross-section downwind of the mountain range Six stations that sample the boundary layer of an urban basin Many configurations, one system, broad science

First deployment of 3-antenna prototype PCAPS (Persistent Cold Pool Study) Salt Lake, Utah, Dec Feb 2011 Side-by-side comparison: 915 MHz wind profiler 449 MHz wind profiler (3 modules) 449 MHz Wind Profiler 915 MHz Wind Profiler (N.B. a lot of fiddling and changes during the 2-months!)

449 MHz 915 MHz 449 Profiler Winds Hardware performed well for most of 2- months Better 449 altitude coverage than 915 Better time resolution is possible Captured the interface between valley flow and mountain crest flow (important for PCAPS science) A day of 30-min winds

449 MHz Comparison with 915 MHz

449 MHz Comparison with 915 MHz High 915 Low Winds percentage vs. Height Altitude coverage about 1 km greater 2 months of operations Median absolute difference < 2 m/s

449 MHz: 5-minute wind resolution 4 hours

449 Next Steps  3-panel prototype works well. Some outstanding questions (e.g. algorithm details; minimum range)  Has allowed us to test components and concepts  Next steps: o Build seven antenna modules o One 7-panel profiler or two 3-panel systems (Two BL or one mid-troposphere profiler) o Status: o Construction underway (working around other commitments) o Testing prototype next summer  Longer term: Mobile-449/ISS, RASS (T v ), Range Imaging  Eventually…develop full 19-module system  Early discussion: how to adapt for ship operations