Spatiotemporal distributions and influences on snow density in China from 1999 to 2008

Ground snow observation data from 1999 to 2008 were used to analyze the temporal and spatial distribution of snow density inChina. The monthly maximum density shifted from north to south during the period from October to the following January, andthen moved back from south to north during the period from January to April. The maximum snow density occurred at the borderbetween Hunan and Jiangxi provinces in January, where snow cover duration was short and varied remarkably. Snow density inNortheast China and the Xinjiang Uygur Autonomous Region were also high and showed less variation when the snow cover durationwas long. Ground observation data from nine weather stations were selected to study changes of snow density in Northeastand Northwest China. A phase of stable snow density occurred from the middle ten days of November to the following February;non-stationary density phases were observed from October to the first ten days of November and from March to April. To furtherinvestigate the effects of climatic factors on snow density, correlations between snow density and precipitation, air temperature,snow depth and wind velocity for Northeast and Northwest China were analyzed. Correlation analysis showed that snow depth wasthe primary influence on snow density.