org: Optical Rain Gauge

The ORG measures rainfall by detecting the optical irregularities induced within the sample volume by precipitating particles falling through a beam of partially coherent infrared light. These irregularities are known as scintillation. By detecting the intensity of the scintillation, the actual rainfall rate can be measured.

This particular rain gauge is an optical independent analog unit consisting of a frame that contains 1) the transmit head, 2) a receive head and electronics, and 3) a 15-meter-long power/signal cable. The transmit head contains an infrared-emitting diode and lens with heater. The other head contains a photodiode, lens and aperture, heater, electronics, and cable connectors. All wiring between the heads runs within the frame.



  • Fixed
  • AMF1
  • AMF2
  • AMF3


Zheng Y and Z Li. 2019. "Episodes of warm‐air advection causing cloud‐surface decoupling during the MARCUS." Journal of Geophysical Research: Atmospheres, 124(22), 10.1029/2019JD030835.
Research Highlight

Tridon F, C Planche, K MROZ, S Banson, A Battaglia, J Van Baelen, and W Wobrock. 2019. "On the realism of the rain microphysics representation of a squall line in the WRF model. Part I: Evaluation with multi-frequency cloud radar Doppler spectra observations." Monthly Weather Review, 147(8), 10.1175/MWR-D-18-0018.1.


Zuidema P, M Alvarado, C Chiu, S DeSzoeke, C Fairall, G Feingold, A Freedman, S Ghan, J Haywood, P Kollias, E Lewis, G McFarquhar, A McComiskey, D Mechem, T Onasch, J Redemann, D Romps, D Turner, H Wang, R Wood, S Yuter, and P Zhu. 2018. Layered Atlantic Smoke Interactions with Clouds (LASIC) Field Campaign Report. Ed. by Robert Stafford, ARM Climate Research Facility. DOE/SC-ARM-18-018.


Bartholomew MJ. 2016. Optical Rain Gauge Instrument Handbook. Ed. by Robert Stafford, DOE ARM Climate Research Facility. DOE/SC-ARM-TR-153.


Chandra A, C Zhang, P Kollias, S Matrosov, and W Szyrmer. 2015. "Automated rain rate estimates using the Ka-band ARM zenith radar (KAZR)." Atmospheric Measurement Techniques, 8(9), 10.5194/amt-8-3685-2015.
Research Highlight


Yoneyama K, C Zhang, and CN Long. 2013. "Tracking Pulses of the Madden–Julian Oscillation." Bulletin of the American Meteorological Society, 94(12), 10.1175/bams-d-12-00157.1.

Deng L, S McFarlane, and J Flaherty. 2013. "Characteristics Associated with the Madden–Julian Oscillation at Manus Island." Journal of Climate, 26(10), 10.1175/jcli-d-12-00312.1.
Research Highlight


Lintner BR, CE Holloway, and JD Neelin. 2011. "Column Water Vapor Statistics and Their Relationship to Deep Convection, Vertical and Horizontal Circulation, and Moisture Structure at Nauru." Journal of Climate, 24(20), 10.1175/jcli-d-10-05015.1.


Voyles JW. 2007. ACRF Instrumentation Status: New, Current, and Future September – October 2007. DOE ARM Climate Research Facility. DOE/SC-ARM/P-07-002.8.

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