近40年波密县积雪时空分布特征分析

Analysis of Spatial and Temporal Distribution Characteristics of Snow Cover in Bomi County in Recent 40 Years

基于1977—2017年的Landsat卫星数据,研究区域积雪季节变化特征以及积雪变化与气候特征之间的响应机制。对Lantsat数据采用面向对象法、雪盖指数法提取波密县流域的积雪像元,研究结果表明,近40年来波密县流域积雪面积在年际尺度上整体面积急剧下降,40年间积雪覆盖率由67%下降至18%,尤其是2007—2017这10年,波密县流域的积雪面积呈现明显下降的趋势。全球气候变暖可能是波密县流域积雪面积不断变小的主要原因。

Based on Landsat satellite data from 1977 to 2017,the seasonal variation characteristics of regional snow cover and the response mechanism between snow change and climate characteristics are studied.For Landsat data,the snow cover index method is used to extract the snow cover pixels in the basin of Bomi county using the object-oriented method.The results show that the total area of snow cover in the basin of Bomi county has declined sharply in the annual scale in recent 40 years,and the snow coverage rate has decreased to 18%in 40 years.Especially in the decade 2007-2017,the snow cover of the basin in Bomi county has been decreasing obviously.Global warming may be the main reason for the decreasing snow area in the basin of Bomi county.