基于微波辐射计的南极冰盖冻融时空变化分析

Analysis of spatio-temporal variation of snowmelt in Antarctica derived from microwave radiometer data

基于改进的小波冻融探测算法,利用SMMR和SSM/I数据对南极冰盖1978年—2010年期间的冻融状况进行监测,分析了南极冰盖近31年(1978—2010)和近10年(2000—2010)的整体和区域冻融时空变化特征,结果表明:南极冰盖冻融变化受南极地区温度变化影响比较明显,两者之间具有一定程度的正相关关系,而且南极冰盖冻融具有南极东部和南极西部两种不同的冻融变化特征,南极西部冰盖冻融变化剧烈,南极东部冰盖冻融变化相对稳定,甚至有减弱趋势。

We derived Melt Extent(ME) and Melt Index(MI) of snowmelt in Antarctica from 1978 to 2010 using satellite passive microwave SMMR and SSM/I data. A modified ice sheet snowmelt detection method based on wavelet transform was developed to determine and characterize melt occurrences. Annual ME and MI data were used to analyze temporal variation in features of snowmelt in Antarctica from 1978 to 2010.In addition, we analyzed variation in snow melt from 2000 to 2010 for comparison; this decade has experienced the greatest changes in global climate. Furthermore, we divided Antarctica into four analysis regions based on the complexity of spatio-temporal variations of snowmelt. We discovered that snowmelt in Antarctica exhibited different temporal patterns in East Antarctica and West Antarctica. The snowmelt in West Antarctica changed dramatically during the first analysis period, while the variations of snowmelt in East Antarctica were more moderate, even appearing to decrease. In addition, we found a positive correlation between variations of snowmelt and variations of temperature in Antarctica, which suggests that temperature changes influenced snowmelt.