Atmospheric Measurement Techniques Discussions www.atmos-meas-tech-discuss.net 1867-8610 2 3 2009 10.5194/amtd-2-1293-2009 http://www.atmos-meas-tech-discuss.net/2/1293/2009/ http://www.atmos-meas-tech-discuss.net/2/1293/2009/amtd-2-1293-2009.html http://www.atmos-meas-tech-discuss.net/2/1293/2009/amtd-2-1293-2009.pdf 1293 1320 2009-05-15 Response of the Nevzorov hot wire probe in Arctic clouds dominated by very large droplet sizes A. Schwarzenboeck G. Mioche A. Armetta A. Herber J.-F. Gayet Laboratoire de Météorologie Physique (LAMP), Université Blaise Pascal, 24 avenue des Landais, 63177 Aubière Cedex, France Alfred Wegener Institute for Polar and Marine Research (AWI), Columbusstrasse, 27568 Bremerhaven, Germany During the airborne research mission ASTAR 2004 (Arctic Study of Tropospheric Aerosols, Clouds and Radiation) performed over the island of Svalbard in the Arctic a constant-temperature hot-wire Nevzorov Probe designed for aircraft measurements, has been used onboard the aircraft POLAR 2. The Nevzorov probe measured liquid water (LWC) and total condensed water content (TWC) in supercooled liquid and partly mixed phase clouds, respectively. As for other hotwire probes the calculation of LWC and/or TWC (and thus the ice water content IWC) has to take into account the collection efficiencies of the two separate sensors for LWC and TWC which both react differently with respect to cloud phase and what is even more difficult to quantify with respect to the size of ice and liquid cloud particles. The study demonstrates that during pure liquid cloud sequences the ASTAR data set of the Nevzorov probe allowed to improve the quantification of the collection efficiency, particularly of the LWC probe part with respect to water. The improved quantification of liquid water content should lead to improved retrievals of IWC content. Simultaneous retrievals of LWC and IWC are correlated with the asymmetry factor derived from the Polar Nephelometer instrument. Baumgardner, D., Strapp, W., and Dye, J. E.: Evaluation of the forward scattering spectrometer probe. Part II: Corrections for coincidence and dead-time losses, J. Atmos. Ocean. 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