Analysis on lake changes since ancient and modern ages using remote sensing in Dagze Co,Tibetan Plateau

Abstract

青藏高原湖泊受人类活动干扰较少,主要受气候变化导致的冰川融化和蒸发的影响,是气候变化直观敏感的反映区。因此,研究青藏高原湖泊变化对区域以至全球气候、环境变化的研究具有深远意义。本文在遥感影像的基础上发展了综合指数计算与空间分异的现存湖迭代提取方法,对影像数据上的湖泊进行动态监测;并结合DEM数据发展了半自动化的古岸线提取方法,进而分析古湖泊的变化,二者相结合直观全面地反映出了青藏高原湖泊的古今变化情况。并以达则错湖为例进行提取,分析了其近25年以来以及大湖期以来的缩减情况.;Lakes on the Tibetan Plateau, which are rarely influenced by disturbance of human activities and mainly controlled byglacier melting and evaporation caused by climate change, are a typical study area of global climate and environment change. Re-mote sensing technology to monitor lake changes across the plateau has important significance to global climate and environmentchange research. This paper developed an iterative modern lake extraction method on remote sensing images using index calculationand spatial difference comprehensively, to detect lake changes dynamically; and developed a semi-automatic paleo-shoreline extrac-lion method combined with DEM, so as to analyze paleo-lake change. Combining the two methods, we can clearly and completely getthe lake changes across the Tibetan Plateau since the ancient and modern ages. Finally, we task Dagze Co as an example to proceedwith the methods, and analyzed its shrinkage conditions since the latest 25 years and since the Great Lake Period.