Declining snowfall fraction in the alpine regions, Central Asia
Declining snowfall fraction in the alpine regions, Central Asia
复制标题
中亚高山地区降雪量下降
DOI：
10.1038/s41598-020-60303-z
复制
发表时间：
2020
影响因子：
4.6
通讯作者：
Wang Yang
中科院分区：
文献类型：
--
作者：
Li Zhi;Chen Yaning;Li Yupeng;Wang Yang
在气候变暖的情况下，降水（P）不太可能以降雪（S）的形式出现。目前认为降雪分数（S/P）的变化不仅影响冰川的积累和消融，而且对山区的径流和水资源也有显着影响。然而，到目前为止，大多数研究都集中在降水量及其频率变化，而降水类型的季节变化大多被忽视。本文采用阈值温度法结合多源数据集（APHRODITE、CPC和气象站）分析确定了中亚天山地区1960-2017年降雪量占降水的比例。结果表明，温度引起的降水由雪转为雨。标准普尔经历了整体下降趋势，在 20 世纪 90 年代中期之前以 0.6%/十年的速度上升，随后以 -0.5%/十年的速度下降。 S/P下降主要发生在中低海拔地区（1500~3500米）。在海拔较高（超过3500米）时，由于温度始终低于冰点，S/P比下降的幅度较小甚至有所增加。 S/P 的减少总是与冰川/雪融补给河流中年流量的减少有关。
In a warming climate, precipitation (P) is less likely to occur as snowfall (S). Change in the snowfall fraction (S/P) is currently assumed not only influences the accumulation and ablation of glaciers, but also influences the streamflow and water resources significantly in mountainous regions. However, until now, most studies have focused on precipitation magnitude and its frequency changes, while seasonal shifts in precipitation types have been mostly neglected. This paper employs the threshold temperature method in combination with multi-source dataset (APHRODITE, CPC and meteorological stations) analysis to determine snowfall proportions in precipitation in the Tienshan Mountains, Central Asia, during 1960–2017. The results indicated that temperature-induced precipitation shifting from snow to rain. The S/P experienced an overall declining trend, increasing at a rate of 0.6%/decade prior to the mid-1990s, followed by a downward trend at a rate of −0.5%/decade. The S/P decreased mainly at low and middle altitudes (between 1500 and 3500 m). At higher altitudes (over 3500 m), the magnitudes of the decreased S/P ratios were small or even increased due to the temperature always being below freezing. Decreases in S/P are always associated with decreases in annual streamflow in the glacier/snow melt recharged rivers.