2000—2020年北疆地区积雪时空变化趋势及影响要素

The temporal and spatial variation trends and influencing factors of snow cover in northern Xinjiang from 2000 to 2020

基于北疆地区29个气象站点2000—2020年积雪数据集,分析了北疆地区20个水文年的积雪天数、年最大雪深、年均雪深、降雪次数、雪物候和气象要素变化,并对其影响要素进行了分析。结果表明,北疆地区近20年来冬季的积雪天数呈显著上升趋势,超过58%的气象站点降雪次数下降趋势显著,这与最低气温和降水量的显著增加密切相关。有72%的站点表现出了温度升高的趋势,近20年北疆地区降水量出现显著增加。雪物候方面,积雪持续天数呈现弱下降趋势,初雪日的出现时间明显推迟,增幅为0.17 d/a。终雪日的推迟并不显著。地理和气象因素与积雪密切相关,尤其是气温和降水量的变化会导致积雪深度发生显著变化,海拔对雪物候的影响程度比气象因素更加明显。

To better study the inter-annual change characteristics of snow cover in northern Xinjiang,snow cover days,annual maximum snow depth,annual snow depth,snow frequency,snow weather and meteorological elements of 20 hydrological years in northern Xinjiang were analyzed based on the snow cover data set from 2000 to 2020,and the influencing factors were also investigated.The results showed that both numbers of snow day in northern Xinjiang in recent 20 years and numbers of snowfall at more than 58%of meteorological stations decreased significantly,which was closely related to the significant increase of minimum temperature and precipitation.72%of the sites showed a trend of increasing temperature and the precipitation in northern Xinjiang increased significantly in the past 20 years.In terms of snow phenology,continuous days of snow showed a weak downward trend and the appearance time of the first snow day was significantly delayed,with an increase of 0.17 days annually,and the delay of the last snow day was not significant.Geographic and meteorological factors were closely related to snow cover,especially changes of temperature and precipitation would lead to significant change in snow depth,and influence of altitude on snow phenology was more obvious than those of the meteorological factors.