丹东地区沿海和山区降雪气候特征

利用丹东地区4个观测站1955—2010年逐年10月至翌年4月逐日降水量、天气现象、雪深等资料,对丹东地区南部沿海和北部山区降雪气候特征进行了分析,结果表明:丹东地区沿海和山区降雪初日、终日及初终日间隔日数、年降雪日数、年降雪量、降水相态、日最大降雪量、日最大积雪深度等平均特征不同。与山区相比,沿海降雪初期较晚,终期较早,初、终日间日数较短,年降雪日数和年降雪量相对较少。在丹东地区1955—2010年降雪时段平均气温升高趋势显著背景下,丹东地区降雪初期推迟、终期提前、初终日间隔日数缩短;降雪日数减少,其中雨夹雪日数所占百分比显著增多;降雪量减少,其中主要是纯雪量减少;日最大降雪量和积雪深度呈减小趋势;沿海和山区变化幅度不同。

Climate Characteristics of Snowfall in Coastal and Mountain Areas of Dandong

Based on the daily precipitation, weather phenomena, and snow depth of four meteorological stations in Dandong from October to the next April from 1955 to 2010, the climate change characteristics of snowfall in Dandong are studied. The results show that in the coastal area of the southern Dandong and the mountain area of the northern Dandong, there are obvious regional differences in beginning dates, ending dates, interval days, the annual number of days with snow, the annual amount of snowfall, precipitation phase state, daily maximum amount of snowfall, and daily maximum depth. Compared with the mountain area, the beginning date was later, and the ending date was earlier in coastal area; the number of days between beginning and ending dates was smaller, and annual number of snowfall days and annual amount of snowfall were less. Under the background of obviously increasing annual mean air temperature from October to next April from 1955 to 2010, the beginning date was delayed, and the ending date was advanced; the intervals were significantly shortened, and the annual numbers of snowfall days were reduced, especially the percentages of the mixed rain and snow days to snowfall days increased obviously; the amount of snowfall reduced, mainly pure snow, and the daily maximum amount of snowfall and the daily maximum depth decreased; the variation extent is different in the coastal area and the mountain area.