Instrument : X-Band Scanning ARM Precipitation Radar (XSAPR)
Beneficiary of Recovery Act funding.
Instrument Categories
Cloud Properties
General Overview
The X-band scanning ARM precipitation radar (X-SAPR) is an X-band dual-polarization Doppler weather radar manufactured by Radtec, Inc. The X-SAPR operates in a simultaneous transmit and receive (STAR) mode, meaning that the transmit signal is split so that power is transmitted on both horizontal and vertical polarizations at the same time. The X-SAPR transmitter is a 200 kW (peak power) magnetron. The receiver is based upon the Vaisala RVP-900 and runs Vaisala’s IRIS software. In addition to the first three Doppler moments (reflectivity, radial velocity, and spectra width), the X-SAPR also provides differential reflectivity, correlation coefficient, and specific differential phases. The dual-polarization variables will allow the provision to provide estimates of rainfall rates and identification of precipitation types. At the Southern Great Plains, there are three X-SAPRs surrounding the Central Facility, providing the capability to use multi-Doppler velocity retrievals to estimate wind fields.
The X-SAPR represents a new measurement capability for ARM.
Output Datastreams
- xsaprhsrhi : X-SAPR Horizon-to-horizon Range-Height Indicator scan
- xsaprppi : X-SAPR Plan Position Indicator scan
- xsaprsur : X-SAPR Surveillance scan
- xsaprvad : X-SAPR Velocity-Azimuth Display scan
- xsaprvpt : X-SAPR Vertical PoinTing scan
Primary Measurements
The following measurements are those considered scientifically relevant.
Locations
- North Slope Alaska (NSA)
- Central Facility, Barrow AK (C1)
- Southern Great Plains (SGP)
- Billings, OK (SE X-band radar site, Intermediate / Auxiliary) (I4)
- Deer Creek, OK (NW X-band radar site, Intermediate / Auxiliary) (I6)
- Garber, OK (SW X-band radar site, Intermediate / Auxiliary) (I5)
Contact(s)
Nitin Bharadwaj
(509) 372-4267
nitin@pnnl.gov
Kevin Widener
(509) 528-9565
kevin.widener@pnnl.gov
Dan Nelson
associate
(509) 375-3868
danny.nelson@pnnl.gov
Iosif (Andrei) Lindenmaier
associate
(509) 375--6802
iosif.lindenmaier@pnnl.gov
Scott Collis
data analysis
630-252-0550
scollis@anl.gov
