Mass wasting and erosion in different morphoclimatic zones of the Makalu Barun region, Nepal Himalaya

Abstract

ABSTRACT Mountain regions of the world face unprecedented climate-induced changes and associated sustainable development challenges. Retreating glaciers, degrading permafrost and rapid mass movements on the one hand and glacier-related disasters, on the other hand, are the sentinels of these phenomena. In this study, we focus our attention on the Makalu Barun region in the Nepal Himalaya, and characterize four main morphoclimatic zones, building on repeated field surveys and interpretation of remote sensing imagery. We distinguish four distinct zones: (i) extreme glacial zone; (ii) glacial zone; (iii) periglacial zone; and (iv) seasonally cold/warm humid zone. While extreme glacial zone is stagnant in its area, remaining three zones have been experiencing areal/location changes associated with changing climate, glacier extent and permafrost distribution. We describe dominant geomorphic processes and typical landforms of these zones in detail, highlighting the role of mass wasting processes and far-reaching process chains acting across distinct morphoclimatic zones. The study provides evidence of very dynamic landform evolution which indicates extreme geomorphological hazards in the Nepal Himalaya.