Cloud and Liquid Water Phase Occurrence in the Arctic Atmosphere

ing the coldest winter months. Arctic cloud phase and occurrence were documented over three seasons by a depolarization lidar that was deployed as part of the Surface Heat Budget of the Arctic Ocean (SHEBA) project during 1997-1998. This unique instrument, which provides range-resolved depolarization ratio indicating phase, documented the occurrence of liquid water phase through the Arctic troposphere, a quantity that has been poorly understood and wholly uncharacterized until recently. We present statistics of cloud and liquid water phase occurrence spanning from 1 November 1997 through 8 August 1998. This unprecedented data set shows that water and/or mixed phase clouds are prevalent over all seasons and throughout most of the atmosphere even dur