Assessment of glacier status and its controlling parameters from 1990 to 2018 of Hunza Basin, Western Karakorum

Abstract

Ice masses and snow of Hunza River Basin (HRB) are an important primary source of fresh water and lifeline for downstream inhabitants. Changing climatic conditions seriously put an impact on these available ice and snow masses. These glaciers may affect downstream population by glacial lake outburst oods (GLOF) and surge events due to climatic variation. So, monitoring of these glaciers and available ice masses are important. This research delivers an approach for selected glaciers of the Hunza river basin. An attempt is made in this study using Landsat (OLI, ETM, ETM+, TM), digital elevation model (DEM), Geographic Information System and Remote Sensing techniques (RS&GIS) techniques. We delineated 27 glaciers within HRB from the period of 1990-2018. These glaciers' total area is about 2589.75 ±86km 2 in 1990 and about 2565.12 ±68km 2 in 2018. Our results revealed that from 2009 to 2015, glacier coverage of HRB advanced with a mean annual advance rate of 2.22±0.1 km 2 a -1 . Conversely, from 1994 to 1999, the strongest reduction in glacier area with a mean rate of -3.126±0.3km 2 a -1 is recorded. The glaciers of HRB are relatively stable compared to Hindukush, Himalayan and Tibetan Plateau (TP) region of the world. The steep slope glacier's retreat rate is more than that of gentle slope glaciers, and the glaciers below elevation of 5000 m above sea level change signi cantly. Based on climate data from 1995-2018, HRB shows a decreasing trend in temperature and increasing precipitation. The glacier area's overall retreat is due to an increase in summer temperature while the glacier advancement is induced possibly by winter and autumn precipitation.

Trend of snow cover under the influence of climate change using Google Earth Engine platform: A case study of Astore (Western Himalayas) and Shigar (Karakoram region)

“…Fowler and Archer, (2006) stated that the summer season's temperature plays a key role in SCA and glacier melt; another study also stated that the pre-monsoon and monsoon temperature of the high mountain area is decreasing (Hussain et al, 2005). The elevation and SCA were also analyzed, and it was found that zone 1 of both regions has a decreasing trend (Qureshi et al, 2017;Ali et al, 2021), while zone 4 has a slightly increasing trend of SCA because the high-altitude region is less exposed to solar radiation as compared to foothills (Saydi and Ding, 2020). The higher altitude regions have consistently below-freezing temperatures throughout the year; therefore, increasing precipitation can possibly feed the high-altitude region, and hence SCA expands (Tahir et al, 2011;Hasson et al, 2014b).…”

Assessing the Karakoram Anomaly from long-term trends in earth observation and climate data

“…The eastern Karakoram (i.e., Shyok sub-basin) receives water input mainly from the summer monsoon while, in the western Karakoram (i.e., Hunza and Shigar sub-basins), precipitation comes mainly during winter and spring via the winter westerly disturbances (WWD; Dahri et al, 2016Dahri et al, , 2018Hasson et al, 2014;Hewitt, 2011;Rees and Collins, 2006). In recent decades, there has been an increasing trend in precipitation amounts observed over the western Karakoram (Ali et al, 2021).…”

Anthropogenic climate change drives melting of glaciers in the Himalaya

“…One of the notable impacts of climate change in the Himalaya is the signi cant glacier thinning and melting (Shrestha and Aryal 2011;Ali et al 2021;Dixit et al 2021). However, the observed thinning and melting is characterized by heterogeneity across the Himalaya (Abdullah et al 2020;Sakai and Fujita 2017;Farinotti et al 2020).…”