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