| 1981-2010年青藏高原降雪日数时空变化特征 |
| |
| 引用本文： | 除多,洛桑曲珍,杨志刚,杨勇.1981-2010年青藏高原降雪日数时空变化特征[J].应用气象学报,2017,28(3):292-305. |
| |
| 作者姓名： | 除多 洛桑曲珍 杨志刚 杨勇 |
| |
| 作者单位： | 1.中国气象局成都高原气象研究所拉萨分部, 拉萨 850000 |
| |
| 基金项目： | 公益性行业（气象）科研专项（GYHY201206040，GYHY201306054），国家自然科学基金项目（41561017） |
| |
| 摘 要： | 利用青藏高原气象站降雪日数观测资料，分析1981-2010年青藏高原降雪日数的时空变化特点和主要影响因素。结果表明:降雪日数总体上呈青藏高原中东部高寒地区、喜马拉雅山脉南麓和祁连山脉流域降雪日数多，南部河谷和北部湖盆区降雪日数少的空间分布格局；春季降雪日数占全年的45%，其次是冬季（28%）和秋季（22%），夏季最少（5%）；30年内青藏高原平均年降雪日数呈明显减少趋势，降幅达10.5 d/（10 a），其中，春季降幅最大（4.8 d/（10 a）），夏季最小（1.2 d/（10 a））；年降雪日数在1997年发生了由多到少的气候突变；降雪日数年内分布呈双峰型，峰值出现在冬夏大气环流的转换季节，青藏高原大气环流的转换期与上升运动相联系的低值天气系统和高空温湿条件均有利于降雪出现；青藏高原降雪日数的明显减少与气温的显著上升呈线性关系。
|
| 关 键 词： | 降雪日数 时空变化 地面观测 青藏高原 |
| 收稿时间： | 2016/10/20 0:00:00 |
| 修稿时间： | 2017/1/20 0:00:00 |
Spatiotemporal Variations of Snowfall Days over the Tibetan Plateau from 1981 to 2010 |
| |
| Chu Duo,Luosang Quzhen,Yang Zhigang and Yang Yong.Spatiotemporal Variations of Snowfall Days over the Tibetan Plateau from 1981 to 2010[J].Quarterly Journal of Applied Meteorology,2017,28(3):292-305. |
| |
| Authors: | Chu Duo Luosang Quzhen Yang Zhigang and Yang Yong |
| |
| Affiliation: | 1.Lhasa Campus of Institute of Plateau Meteorology, CMA, Lhasa 8500002.Tibet Institute of Plateau Atmospheric and Environmental Sciences, Lhasa 8500003.Tibet Climate Center, Lhasa 850000 |
| |
| Abstract: | Snow is a vital component of alpine regions due to its large seasonal variations and distinctive physical properties, it greatly affects climate, hydrology, and ecology at regional and global scales. The Tibetan Plateau (TP), also called "the roof of the world", is the highest land and typical alpine region on the earth with over 4000 m above sea level. Snow on the TP is a vital fresh water source in the Himalayan region and downstream areas, and also a significant indicator of climate change from regional to global scales. Therefore, under global climate warming, the variation of snowfall days over the TP, which is defined as the number of days with snowfall (including sleet) weather at a station from 2000 BT to 2000 BT, is concerned by international scientific community and local people.Spatial and temporal variations of snowfall days over the TP are analyzed using snow observations from 94 meteorological stations for the period from 1981 to 2010, and the following results are obtained. Snowfall days over the TP are generally characterized by more snowfall days in the central and eastern alpine region, southern slope of the Himalayan range and the Qilian mountains in the northeast, and less snowfall days in valleys in south and the Qaidam Basin in the north. The number of averaged annual snowfall days for the TP is 60 days, of which 45% occurs in spring, 28% in winter, 22% in autumn and 5% in summer, respectively. There is a very significant decreasing trend in mean annual snowfall days from 1981 to 2010 over the TP with a rate of 10.5 days per decade. The abrupt climate change of snowfall days from more to less occurs around 1997 and in the later 10 years, annual snowfall days decrease obviously especially in 2010, which is an anomalous snowless year. Intra-annual distribution of snowfall days over the TP is characterized by double-peak type. The first peak occurs during transition period of atmospheric circulation from winter to summer and the second peak takes place in transition period of atmospheric circulations from summer to winter with less peak value. During the transition time of atmospheric circulation, low value weather system along with upward air movement and temperature and humidity conditions in the upper air is favorable for snowfall over the TP. A very significant correlation exists between decrease in snowfall days and increase in temperature from 1981 to 2010 over the TP. Under global warming and more rapid temperature increasing on the TP, the rainfall previously in snow form converts into liquid rainfall, which may significantly contribute to the decrease of snowfall days over the TP in the recent 30 years. |
| |
| Keywords: | snowfall days spatio-temporal variation ground observation the Tibetan Plateau |
|
| 点击此处可从《应用气象学报》浏览原始摘要信息 |
|
点击此处可从《应用气象学报》下载全文 |
|
