csapr: C-Band Scanning ARM Precipitation Radar

The C-Band Scanning ARM Precipitation Radar is a dual-polarization Doppler weather radar that operates in a simultaneous transmit and receive (STAR) mode, splitting the transmit signal so that power is transmitted on both horizontal and vertical polarizations at the same time. The C-SAPR can also transmit on a single polarization (horizontal or vertical) and measure linear depolarization ratio (LDR).
In addition to the first three Doppler moments (reflectivity, radial velocity, and spectra width), the C-SAPR also provides differential reflectivity, correlation coefficient, and specific differential phase. The dual-polarization variables enable the provision of rainfall rate estimates and identification of precipitation types.



  • Fixed
  • AMF1
  • AMF2
  • AMF3

Active Instrument Locations

Facility Name Instrument Start Date
Graciosa Island, Azores, Portugal 2019-10-24
CGA (Calibration, Grooming, and Alignment) Data 2019-10-24
Central Facility, Lamont, OK 2019-10-24


Matsui T, B Dolan, T Iguchi, S Rutledge, W Tao, and S Lang. 2020. "Polarimetric Radar Characteristics of Simulated and Observed Intense Convective Cores for a Midlatitude Continental and Tropical Maritime Environment." Journal of Hydrometeorology, 21(3), 10.1175/JHM-D-19-0185.1.


Kollias P, N Bharadwaj, E Clothiaux, K Lamer, M Oue, J Hardin, B Isom, I Lindenmaier, A Matthews, E Luke, S Giangrande, K Johnson, S Collis, J Comstock, and J Mather. 2019. "The ARM Radar Network: At the Leading-edge of Cloud and Precipitation Observations." Bulletin of the American Meteorological Society, , 10.1175/BAMS-D-18-0288.1. ONLINE.

Borque P, S Nesbitt, R Trapp, S Lasher-Trapp, and M Oue. 2019. "Observational study of the thermodynamics and morphological characteristics of a midlatitude continental cold pool event." Monthly Weather Review, 148(2), 10.1175/MWR-D-19-0068.1.

Varble A, S Nesbitt, P Salio, E Avila, P Borque, P DeMott, G McFarquhar, S van den Heever, E Zipser, D Gochis, R Houze, M Jensen, P Kollias, S Kreidenweis, R Leung, K Rasmussen, D Romps, and C Williams. 2019. Cloud, Aerosol, and Complex Terrain Interactions (CACTI) Field Campaign Report. Ed. by Robert Stafford, ARM user facility. DOE/SC-ARM-19-028.

Dorsey K. 2019. Tracking Aerosol Convection interactions ExpeRiment. Ed. by Rolanda Jundt, ARM user facility. DOE/SC-ARM-19-024.

Jensen M, E Bruning, D Collins, A Fridlind, P Kollias, C Kuang, D Rosenfeld, A Ryzhkov, A Varble, SD Brooks, S Collis, E Defer, J Fan, J Flynn, S Giangrande, R Griffin, J Hu, R Jackson, M Kumjian, T Logan, T Matsui, G McFarquhar, C Nowotarski, J Quaas, M Oue, R Sheesley, J Snyder, P Stier, S Usenko, S van den Heever, M van Lier Walqui, Y Wang, Y Xu, and G Zhang. 2019. Tracking Aerosol Convection Interactions ExpeRiment (TRACER) Science Plan. Ed. by Robert Stafford, DOE/SC-ARM-19-017.

Matsui T, B Dolan, S Rutledge, W Tao, T Iguchi, J Barnum, and S Lang. 2019. "POLARRIS: A POLArimetric Radar Retrieval and Instrument Simulator." Journal of Geophysical Research: Atmospheres, 124(8), doi:10.1029/2018JD028317.
Research Highlight

Wood R, G Zhang, N Hickmon, M Jensen, S Klein, R Leung, D Mechem, and P Zuidema. 2019. Atmospheric Radiation Measurement (ARM) User Facility ARM Mobile Facility Workshop Report. Ed. by Rolanda Jundt, Robert Stafford, U.S. Department of Energy Office of Science. DOE/SC-0197.

Oue M, P Kollias, A Shapiro, A Tatarevic, and T Matsui. 2019. "Investigation of observational error sources in multi-Doppler-radar three-dimensional variational vertical air motion retrievals." Atmospheric Measurement Techniques, 12(3), doi:10.5194/amt-12-1999-2019.
Research Highlight

Ghate V, P Kollias, S Crewell, A Fridlind, T Heus, U Löehnert, M Maahn, G McFarquhar, D Moisseev, M Oue, M Wendisch, and C Williams. 2019. "The Second ARM Training and Science Application Event: Training the Next Generation of Atmospheric Scientists." Bulletin of the American Meteorological Society, 100(1), 10.1175/BAMS-D-18-0242.1.

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