摘要
积雪是冰冻圈最重要的组成部分,影响着大气环流和区域水量平衡,对气候变化十分敏感。本文基于2000—2019年MODIS/Terra积雪产品数据,探讨了青藏高原近20年积雪的年内、年际和季节性时空特征及其变化趋势。结果表明:(1)2000—2019年青藏高原积雪以短期积雪为主,积雪期在1个月及以下时间段内的积雪空间分布范围最广,占积雪总面积的72.91%;积雪期越长,多年平均积雪率(SCR)越高,SCR呈高原四周山脉高,而羌塘高原、江河源区、柴达木-黄湟高中盆地等地低的特点。(2)2000—2019年积雪面积呈反复的先波动增加再波动减少,距平变化率在-15.97%~11.52%之间。横断山区、帕米尔高原以及羌塘高原大部分地区的SCR呈明显减少趋势;高原四周极大/大起伏高山/极高山区、江河源丘状高山原和江河上游中/大起伏高山区的SCR呈显著增加趋势。(3)年内积雪面积呈双峰型周期变化趋势,3月和11月达到峰值,8月达到谷值,与该区域多年平均气温、降水等气候因子的年内周期性变化相反。青藏高原冬季积雪分布最广,秋季和春季积雪范围次之,夏季积雪范围最小;2000—2019年,青藏高原东部和南部冬季积雪显著增加、秋季和春季积雪显著减少,青藏高原整体夏季积雪显著减少。(4)近20年,青藏高原积雪与气温、降水的相关程度均较强,积雪覆盖范围与气温呈负相关关系,与降水呈正相关关系。研究结果有助于掌握青藏高原冰雪融水变化情况,对区域水量平衡和气候变化有重要指示作用。
Snow cover,as the most important component of the cryosphere,affects the atmospheric circulation and regional water balance,and is very sensitive to climate change.Using 8-day snow cover data of the Moderate Resolution Imaging Spectro-radiometer/Terra(MODIS/Terra)from 2000 to 2019,the interannual,annual,and seasonal spatiotemporal characteristics of snow cover in the Qinghai-Tibetan Plateau(QTP)and its variation trends were discussed.The results show that:(1)In recent 20 years,the snow cover in the QTP consisted largely of short-term snow.The spatial distribution of snow cover with one month or shorter duration was the widest,accounting for 72.91%of the total snow-covered area.The longer the snow duration,the higher the snow cover ratio(SCR).The multi-year mean SCR in the mountains surrounding the QTP was high,while the SCR was low in the Qiangtang Plateau,the source region of the rivers,and the QaidamHuanghuang high-medium basin,among others.(2)Snow cover area showed repeated fluctuating increase and then decrease with a relative change rate of-15.97%~11.52%during 2000-2019 in the QTP.Snow cover ratio in most areas of the Hengduan Mountains,the Pamirs Plateau,and the Qiangtang Plateau showed an obvious decreasing trend.In the areas surrounding the QTP with high mountains and extremely high mountains of huge difference in relief,hilly mountain plain in the source area of the Yangtze River and the Yellow River,and high mountain areas of medium or great difference in relief of the upper reaches of the Yangtze River and the Yellow River,a significant increasing trend of SCR in recent 20 years was observed.(3)The snow-covered area showed a bimodal cyclical trend annually,reaching the peak in March and November and the lowest in August,which was in contrary to the periodic change of air temperature,precipitation,and other climate factors in this region.The widest spatial distribution of snow cover was in the winter,followed by the autumn and the spring,and the smallest was in the summer.In recent 20 years,the snow cover increased significantly in the winter in eastern and southern QTP,and decreased significantly in the autumn and the spring.The snow cover decreased in the summer in the whole QTP.(4)The correlations between snow cover and air temperature and precipitation were strong.Snow cover had a negative correlation with air temperature and a positive correlation with precipitation.The results of the study are useful for understanding the situation of ice and snow melting water change and are indicative of the regional water balance and climate change of the QTP.
作者
叶红
易桂花
张廷斌
周小兵
李景吉
别小娟
申一林
杨正兰
YE Hong;YI Guihua;ZHANG Tingbin;ZHOU Xiaobing;LI Jingji;BIE Xiaojuan;SHEN Yilin;YANG Zhenglan(College of Earth Science,Chengdu University of Technology,Chengdu 610059,China;College of Tourism and Urban and Rural Planning,Chengdu University of Technology,Chengdu 610059,China;State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil&Water Pollution,Chengdu 610059,China;Geophysical Engineering Department,Montana Tech of the University of Montana,Butter 59701,USA;College of Ecological Environment,Chengdu University of Technology,Chengdu 610059,China)
出处
《资源科学》
CSSCI
CSCD
北大核心
2020年第12期2434-2450,共17页
Resources Science
基金
国家自然科学基金项目(41801099)
第二次青藏高原综合科学考察研究项目(2019QZKK0307)。
