A simple model to evaluate ice melt over the ablation area of glaciers in the Central Karakoram National Park, Pakistan

U Minora,G Diolaiuti,A Senese,R Ambrosini,D Bocchiola,A Soncini,E Vuillermoz,C Mayer,A Lambrecht,C D’Agata,C Smiraglia

doi:10.3189/2015aog70a206

Abstract

AbstractThis study provides an estimate of fresh water derived from ice melt for the ablation areas of glaciers in the Central Karakoram National Park (CKNP), Pakistan. In the CKNP there are ~700 glaciers, covering ~4600 km2, with widespread debris cover (518 km2). To assess meltwater volume we applied a distributed model able to describe both debris-covered and debris-free ice ablation. The model was calibrated using data collected in the field in the CKNP area and validated by comparison with ablation data collected in the field, independent of the data used in building the model. During 23 July–9 August 2011, the mean model-estimated ablation in the CKNP was 0.024 m w.e. d–1 in debris-covered areas and 0.037 m w.e. d–1 in debris-free areas. We found a mean error of +0.01 m w.e. (corresponding to 2%) and a root-mean-square error equal to 0.09 m w.e. (17%). According to our model, the ablation areas of all the glaciers in the CKNP produced a water volume of 1.963 km3 during the study period. Finally, we performed several sensitivity tests for assessing the impact of the input data variations.

Highlights

The largest glacierized region outside the Arctic and the Antarctic is High Mountain Asia (HMA), which covers an area of 118 200 km2 (Gardner and others, 2013)
This study focuses on the glacier ablation areas within the Central Karakoram National Park (CKNP), with the aim of assessing the magnitude and rate of ice ablation and evaluating the derived meltwater amount
Since snow depth data in the CKNP area are scant and spotty, our study focused on modeling ice melt only, neglecting snowmelt

Summary

Introduction

The largest glacierized region outside the Arctic and the Antarctic is High Mountain Asia (HMA), which covers an area of 118 200 km (Gardner and others, 2013). Advances of individual glaciers have been reported in the Shyok valley (eastern Karakoram) during the last decade (Raina and Srivastva, 2008). These individual advances and mass gain episodes could be attributed to surging (Barrand and Murray, 2006; Hewitt, 2007; Copland and others, 2011; Quincey and others, 2011), temperature drops (Shekhar and others, 2010) and increased solid precipitation in the accumulation areas (Fowler and Archer, 2006; Bocchiola and Diolaiuti, 2013). The glacierized Karakoram is a key area for studying the effects of ongoing climate change on present and future meltwater discharge

Methods

Results

Discussion

Conclusion