MAPRMAPR Multiple Antenna Profiler RadarMultiple Antenna Profiler Radar

Steve Cohn, Dave Parsons (Science)

Eleanor Praskovskaya (Science)

Mike Susedik (Hardware)

Charlie Martin & Gordon Maclean (Software)

William Brown

National Center for Atmospheric Research

Support from DOE’s ARM and VTMX Programsand NCAR / ATD

DBSDBS

MAPRMAPR

MAPR compared with MAPR compared with conventional DBS profilersconventional DBS profilers

Disadvantages• MAPR requires 4 antennas and receivers• Data analysis more sophisticated• Less sensitivity so more powerful transmitter required

Advantages• MAPR can make a much faster wind measurement• MAPR provides continuous measurements• MAPR does not need mechanical phase switches

MAPR - SpecsMAPR - Specs

Transmitter Peak Power: 500W (soon to be upgraded to 4kW) Duty Cycle: 10 - 15% Receivers: 4 x Radian (soon to be replaced by PIRAQ) Antenna: standard Radian 4 panel, 64 element array (split

in 4 for receiving) Beam Width: 8 deg (HWHM) Resolution: 60, 105, 210 m (depending on SNR) Typical range: 2 - 5 km (clear-air) Typical time resolution: 1 minute (15

sec in high SNR, 10 minutes in low SNR) Data: netCDF (raw & spectra) or consensus wind files Real-time wind analysis produces plots on the Web

MAPRMAPR

NOAA BAO 300m towerMAPR with clutter screen

Last NightLast Night

MAPR wind measurements (MAPR wind measurements () ) Anemometer measurements (Anemometer measurements (lineline) BAO tower (300m)) BAO tower (300m)

Clear-air echoes

Good agreement between MAPR and Anemometer wind measurements

About 80% of measure-ments agree to 2m/s

Cold FrontCold Front

• MAPR and tower observations

•Note the brief updraft (red) in clear-air ahead of the front

• MAPR can make continuous and rapid 3D wind measurements

Cold FrontCold Front

Note the strong downdraft, followed by a strong updraft at the leading edge of the front.

The frontal passage at the surface was weak.

The periodic up and down motions, which follow, suggests gravity waves.

Nauru99Nauru99

MAPR operated for 1 month at sea for DOE/ARM’s Tropical Western Pacific campaign, Nauru99

Nauru99Nauru99

MAPR Observations of squalls (rain & clear-air)

Note the wind gusts (orange/red wind barbs) and updrafts (yellow/red) in clear-air around squalls

Turbulence MeasurementTurbulence Measurement

MAPR can estimate turbulent intensity

Doppler spectral width is related to velocity variance measured by a sonic anemometer

Overall goals for MAPROverall goals for MAPR

Rapid measurement of the 3-D wind Estimates of turbulent intensity Rapid Deployment Detection of three-dimensional winds and heat

flux from applying spaced antenna techniques to radio acoustic sounding system (RASS)

Incorporation of multiple wavelengths and FDI processing to detect and monitor the evolution of fine-scale refractivity layers