期刊
GLOBAL AND PLANETARY CHANGE
卷 181, 期 -, 页码 -出版社
ELSEVIER
DOI: 10.1016/j.gloplacha.2019.102999
关键词
Rock glacier; Debris-covered glacier; Transitional processes; Clast form; Transport pathways; Landscape continuum
资金
- Natural Environment Research Council [NE/L002434/1]
- Royal Geographical Society through a Dudley Stamp Memorial Award
- IBG
In many of the world's high mountain systems, glacier recession in response to climate change is accompanied by a paraglacial response whereby glaciers are undergoing a transition to rock glaciers. We hypothesise that this transition has important implications for hydrological resources in high mountain systems and the surrounding lowlands given the insulating effects that debris cover can have on glacier ice. Despite this, however, little is known about how this transition occurs nor how quickly, which glaciers are liable to transition, the factors driving this process and the water supply implications that follow. This paper assesses the role of glacier and rock glacier textural properties from a deglaciating region of the Himalayas to begin to address some of these issues. We investigated six landsystems on the spectrum from glaciers-to-rock glaciers in the Khumbu Himal, Nepal, and sampled for clast shape and roundness during 2016 and 2017. Kite aerial photography was additionally used to capture aerial images of an ongoing glacier-to-rock glacier transitional landform (Chola Glacier) to elucidate the surface geomorphic features of a fully transitioned landform. This image data, processed using a structure-from motion multi-view stereo photogrammetry approach, revealed the presence of a spatially coherent ridge-and furrow surface morphology in the lower reaches of Chola Glacier, which is potentially indicative of an ongoing glacier-to-rock glacier transition. We show that glacier-derived and slope-derived clast roundness significantly statistically different (Kolmogorov Smimov two-sample test: D-max = 0.62, two-tail p <.001; n = 1650) and suggest that sediment connectivity (i.e. linkage between sediment sources and downslope landforms) is one of the drivers of the transition process. Consequently, we hypothesise that the presence of well-developed lateral moraines along glacier margins serves to reduce this connectivity and thus the likelihood of glacier-to-rock glacier transition occurring. Understanding such processes has implications for predicting the geomorphological evolution of deglacierizing mountains under future climate warming and the water supply consequences that follow.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据