Assessment of Snow Cover Vulnerability over the Qinghai-Tibetan Plateau

由在 Qinghai 西藏的高原(QTP ) 上从 98 个气象学的车站使用每日的空气温度和降水数据，和每日的降雪的天气现象数据，这份报纸在温暖状况的当前的气候状况和未来气候下面在 QTP 上在降雪和积累的雪上执行在风险评估。当降雨，降雪，或积累的雪天气现象发生时，批评价值为当前的气候条件基于每日的空气温度和降水被决定。0 潣摮瑩潩敮 ? 湩畤瑳祲愠摮愠慮祬敺 ? 桴 ? 湥楶潲浮湥慴? 敢敮楦獴漠 ? 捡散敬慲楴杮琠敨瀠慨敳漭瑵漠 ? 的空气温度 ?? 木′湩 ?

By using daily air temperature and precipitation data, and the weather phenomena data of daily snowfall from 98 meteorological stations over the Qinghai-Tibetan Plateau （QTP）, this paper performs an ＂at-risk＂ evaluation on snowfall and accumulated snow over the QTP under current climate situation and future climate warming condition. When rainfall, snowfall, or accumulated snow weather phenomena occur, critical values are determined based on dally air temperature and precipitation for current climate conditions. Air temperature of 0 ℃ is defined as the critical value of temperature for rainfall or snowfall, while 0 ℃ air temperature and 4.0 mm （autumn） or 3.0 mm （spring） snowfall amounts are defined as the critical values for accumulated snowfall. Analyses based on the above critical values disclose that under current climate condition, stations with ＂at-risk＂ accumulated snow account for 33% and 36% of all stations, and the ＂at-risk＂ snowfall stations reach 78% and 81% in autumn and spring, respectively. Spatially, most stations with ＂at-risk＂ accumulated snow are located on the southern and eastern edge of the QTP, and stations with ＂at-risk＂ snowfall are also apparent at the northern edge. If the air temperature increases by 2.5 ℃ in 2050, only the snowfall at a few ＂at-risk＂ snowfall stations will transform into rainfall, while most ＂at-risk＂ accumulated snow stations will face the problem that snowfall is hardly accumulated. Additionally, most stations will become ＂at-risk＂ accumulated snow stations, indicating that both the snow depth and the snow cover duration will decline in most areas of the QTP, including a delay of the start date and an advancing of the end date of snow cover.