Seasonal variation in vertical distribution of cloud and snowfall obtained by ceilometer at Dome Fuji Station

Abstract

A ceilometer was operated at Dome Fuji Station during the 44th Japanese Antarctic Research Expedition from February 2003 to January 2004. This report describes characteristics of the vertical distribution of cloud and snowfall using the backscattering coefficient obtained from the ceilometer. Optically thick cloud in the layer lower than 500m above the surface appears more frequently in summer season (February 2003, December 2003 and January 2004) than in other seasons. In the upper troposphere from 3000m to 5000m height above the surface (that is, from approximately 7000m to 9000m above sea level), moderate clouds appear relatively frequently from April to October. In many cases in the polar night, snowfall events in the layer lower than 1500m give rise to a backscatter coefficient that decreases with height, which is characteristic of a streaky snowfall distribution in a height -time section.