a deployable modular wind profiler radar for lower atmosphere applications william brown, steve...
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A deployable modular wind profiler RADAR for lower atmosphere applications
William Brown, Steve Cohn, Brad Lindseth
National Center for Atmospheric ResearchBoulder, Colorado, USA
With help from:
Jim Jordan, Dan Law, Warner Ecklund
NOAA
9th ISTPL’Aquila, Italy. 3-7 September 2012
NCAR: Earth Observing Laboratory
Operates a wide range of instruments and aircraft for the scientific community
Available by request to National Science Foundation
Current radar wind profilers
• Four LAP3000 profilers• 915 MHz 400W
(+ 1290MHz)• Boundary layer only• Clutter screen• Older technology
• DBS Winds• 15 – 30 minutes
Typically deployed with Integrated Sounding System
DYNAMO / CINDY•Indian Ocean•MJO Study
Wide range of science targetsBut:•Inflexible•One size fits all
Wind Profilers : 40+ projectsCommon Science Targets
Tropical storms and dynamics
Severe storms and fronts
Mountain-valley flows
Winter storms
Lake and marine effects
Ice/raindrop fall speed and evolution
Boundary layer height and entrainment
Turbulence effects on aviation safety
New: 449 MHz Wind Profiler
449 MHz Modular Wind Profiler
• Longer wavelength enables higher altitudes
• Fast wind measurements (spaced antenna)
• Modular to give more flexibility
• Combine modules to make radars of varying sizes
• Easy to deploy
• No clutter screen
• Light-weight modules
HexagonalModule
Boundary Layer Config.3 antenna modulesNetwork of 6
Mid-Tropospheric Config.7 antenna modulesNetwork of 2
Lower Stratospheric Config.19 antenna modules
200 m – 7 km30-200 m
300 m – 15 km100-200 m
Range:Resolution:
150 m – 4 km30 m
Not
to s
cale
!
One module
Modular Antennas
With 19 modules :
Example: T-REX
First deployment of 3-antenna prototype
PCAPS (Persistent Cold Pool Study)
Salt Lake, Utah, Dec 2010 - Feb 2011
Side-by-side comparison:• 915 MHz wind profiler• 449 MHz wind profiler (3 modules, 2kW)
449 MHz Wind Profiler
915 MHz Wind Profiler
449 MHz
915 MHz
449 Profiler Winds• 2-month deployment • Hardware performed well• 449 Better altitude coverage than 915
• Better time resolution
• Captured the interface between valley flow and mountain crest flow (important for PCAPS science)
Comparisons
24 hours
4 k
m
449 MHz Comparison with 915 MHz
449915 High
915 Low
Winds percentagevs. Height
• Altitude coverage about 1 km greater
• 2 months
• Median absolute difference < 1.5 m/s
449 MHz: 5-minute winds
Fast wind measurement enables study of rapidly evolving events
Squall over Boulder
w
2 hours
10
km
Wind Profiler:449 MHz radar
Latest developments
Expansion to 7 panels
So far using: 2 kW TX amp 3 channel data system
Coming soon:16 kW TX amp7 channel data systemWinds thru much of troposphere
7-panel first obsWinds to 6 – 8 km in clear-airTwice as high as 915MHz
449 MHz915 MHzSonde
Next step: RIM
• Range IMaging• Enables improvement in range resolution• Small inter-pulse steps in wavelength• Aiming to go from 150 m down to < 50 m
Summary Prototype systems working well Completing seven antenna modules
o One 7-panel profiler OR two 3-panel systems(Two BL or one mid-troposphere profiler)
Next Stepso Adding power (up to 16 kW)o Adding channels (3 -> 7)o Improving lower levelso Improve processing and QCo Adding RIM
Three user proposals received already
Longer term: Mobile truck based profiler, RASS (Tv) Considering how to adapt for ship operations Eventually…develop full 19-module system