Atmospheric Radiation Measurement Climate Research Facility US Department of Energy

wacr > W-Band (95 GHz) ARM Cloud RadarInstrument Type(s) > Baseline

The W-band ARM Cloud Radar (WACR) systems are zenith-pointing Doppler radars that probe the extent and composition of clouds at 95.04 GHz.

The main purpose of this radar is to determine cloud boundaries (e.g., cloud bottoms and tops).

This radar reports estimates for the first three spectra moments for each range gate up to 15 km. The 0th moment is reflectivity, the 1st moment is radial velocity, and the 2nd moment is spectral width. Also available are the raw spectra files.

Unlike the millimeter wavelength cloud radar (MMCR), the WACR does not use pulse coding and operates in only copolarization and cross-polarization modes.

Primary Derived Measurements


  • Fixed
  • AMF1
  • AMF2
  • AMF3


Theisen A, A Lindenmaier, JH Mather, J Comstock, S Collis, and S Giangrande. 2021. ARM FY2022 Radar Plan. Ed. by Robert Stafford, ARM user facility. DOE/SC-ARM-TR-273. 10.2172/1826575.

Mayta V and Á Adames. 2021. "2-Day Westward-Propagating Inertio-Gravity Waves during GoAmazon." Journal of the Atmospheric Sciences, 78(11), 10.1175/JAS-D-20-0358.1.

HENKES A, G Fisch, L Machado, and J Chaboureau. 2021. "Morning boundary layer conditions for shallow to deep convective cloud evolution during the dry season in the central Amazon." Atmospheric Chemistry and Physics, 21(17), 10.5194/acp-21-13207-2021.

Eissner J, D Mechem, M Jensen, and S Giangrande. 2021. "Factors Governing Cloud Growth and Entrainment Rates in Shallow Cumulus and Cumulus Congestus during GoAmazon2014/5." Journal of Geophysical Research: Atmospheres, 126(12), e2021JD034722, 10.1029/2021JD034722.
Research Highlight

Biscaro T, L Machado, S Giangrande, and M Jensen. 2021. "What drives daily precipitation over the central Amazon? Differences observed between wet and dry seasons." Atmospheric Chemistry and Physics, 21(9), 10.5194/acp-21-6735-2021.
Research Highlight

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