Changes of glaciers and glacial lakes implying corridor-barrier effects and climate change in the Hengduan Shan, southeastern Tibetan Plateau

Changes of glaciers and glacial lakes and their causes were examined in the Hengduan Shan from 1990 to 2014, based on Landsat TM/ETM+/OLI images. A total glacier area of 1298.8 +/- 62.1 km(2) and glacial lake area of 255.8 +/- 31.6 km were inventoried in 2014. The area of glaciers declined at an average rate of -0.40 +/- 0.26% a(-1), while glacial lakes expanded at average rate of +0.12 +/- 0.03% a(-1) over the past 24 years. These changes probably resulted from an observable temperature increase and slight precipitation increase. A 'corridor-barrier' effect formed by the longitudinal range-gorge terrain may have had major impacts on the distributions and changes of glaciers and glacial lakes. The Ningjing-Yunling Shan, where glaciers and glacial lakes are sparsely distributed, are an important geographic transition line in the Hengduan Shan because of the barrier effect of the mountain ranges against moisture from the southwest. In contrast, between the south and north, there were small differences with respect to the distributions and changes of glaciers and glacial lakes, owing to a north-south corridor effect for water and heat transport and diffusion through the longitudinal gorges in the Hengduan Shan.