2000~2010年吉林省积雪时空变化特征及其与气候的关系

利用Terra卫星提供的2000年10月1日到2010年4月30日每日雪覆盖产品MOD10A1,提取研究区积雪覆盖指数SCI、积雪日数SCD、积雪初日SCOD及积雪终日SCMD遥感信息,结合同期吉林省界内23个地面气象观测站的同期气温和降水资料,分析该区积雪的变化特征与气温和降水的关系。结果表明:① 吉林省大部分地区积雪日数为30~90 d,东部山区积雪持续时间长、积雪初日日期早以及积雪终日日期晚,中西部地区变化情况相反;② 积雪覆盖指数SCI呈波浪式变化,与积雪季气温呈负相关;③ 积雪日数与气温呈反相关、与降水量呈正相关,与积雪季气温、夏季降水量的相关系数分别为-0.7407、0.6875;积雪初日情况相反,与积雪季气温、夏季平均气温为0.743、0.5479;积雪终日与气温呈反相关、与降水量呈正相关,与积雪季气温、夏季降水量为-0.5214、0.4647。积雪指数均对气温的变化更敏感,气温升高导致积雪初日推迟、积雪终日提前,从而使积雪日数减小;积雪季降水量的增加有利于积雪日数增大,而积雪终日的推迟有利于夏季降水量的增加。

Spatio-temporal Variation of Snow Cover in Jilin Province and Its Relationships to Climate Change in Recent 10 Years

Based on MODIS/Terra Snow Cover Daily Data MOD10A1,the snow spatial-temporal information of Jilin province including snow cover duration(SCD),snow cover onset dates(SCOD) and snow cover melting date(SCMD),are extracted and the variation characteristics are also analyzed.Then,the relationship between snow cover and climate are analyzed.And the climate data covers the temperature and precipitation data of 23 base stations in recent 10 years.The result shows that snow cover duration spans from 30 to 90 days in most regions of Jilin;it is in the eastern area that snow cover lasts for a longer time,SCOD begins earlier and SCMD ends later.There is a negative relationship between SCD and temperature and a positive relationship between SCD and precipitation,with coefficients of-0.7407 and 0.6875 of temperature in snow season and precipitation in summer respectively;there is a negative relationship between SCMD and temperature and a positive relationship between SCMD and precipitation,with coefficients of-0.5414 and 0.4647;on the contrary,with coefficients of 0.7430 and 0.5479 respectively.In all,snow remote sensing information were more sensitive to temperature than to precipitation,as well as to snow season than to summer;The lower the temperature was and the more the precipitation was,the longer the duration of snow cover.Temperature is more essential for maintaining snow cover.