Glacier area stability in the Central Karakoram National Park (Pakistan) in 2001–2010

Abstract

The Karakoram Range is one of the most glacierized mountain regions in the world, and glaciers there are an important water resource for Pakistan. The attention paid to this area is increasing because its glaciers remained rather stable in the early twenty-first century, in contrast to the general glacier retreat observed worldwide on average. This condition is also known as “Karakoram Anomaly”. Here we focus on the recent evolution of glaciers within the Central Karakoram National Park (CKNP, area: *13,000 km2) to assess their status in this region with respect to the described anomaly. A glacier inventory was produced for the years 2001 and 2010, using Landsat images. In total, 711 ice-bodies were detected and digitized, covering an area of 4605.9 ± 86.1 km2 in 2001 and 4606.3 ± 183.7 km2 in 2010, with abundant supraglacial debris cover. The difference between the area values of 2001 and 2010 is not significant (+0.4 ± 202.9 km2), confirming the anomalous behavior of glaciers in this region. The causes of such an anomaly may be various. The increase of snow cover areas from 2001 to 2011 detected using MODIS snow data; the reduction of mean summer temperatures; and the augmented snowfall events during 1980–2009 observed at meteorological stations and confirmed by the available literature, are climatic factors associated with positive mass balances. Because the response of glacier area change to climate variation is very slow for large glaciers, the presence of some of the largest glaciers of the Karakoram Range in this region might have delayed observed effects of such climate change so far, or alternatively, the change may not be sufficient to drive an actual area increase. In this context, improved understanding the role of debris cover, meltwater ponds, and exposed ice cliffs on debris-covered glaciers, and surging glaciers (which are also found abundant here), are required is still an issue to clarify the mechanisms behind the Karakoram Anomaly.

Future Water Availability from Hindukush-Karakoram-Himalaya upper Indus Basin under Conflicting Climate Change Scenarios

“…Worth noting fact is that substantial reduction in the glacier melt, aside changes in precipitation that are also positive, indicates a positive change in the frozen water resources of the UIB. Such finding is largely consistent with the prevailing changes depicted from the long-term observed streamflow record ( Figure 5) and with the reports of anomalously positive or stable glacial mass balances and extents [20,22,[27][28][29]31,[33][34][35], increasing snow covers and falling end-of-summer regional snow line altitudes [20,22,25,26], and subsequent reduction in the melt season discharges [4,19]. On the other hand, a decrease in the glacier melt and in the overall discharge is in direct contrast to the reports from earlier studies, which addressing only partially the climatic uncertainty over the UIB assess its future water availability under warmer climates [5][6][7][8]90], and suggest rather enhanced glacial melt and rise in the water availability throughout the 21st century.…”

“…Such debris-covered glacial extent appears to be stable over time as either no or near-zero change has been reported for 93 Karakoram glaciers investigated over the 1977-2014 period [69]. Further, the analysis over more than 700 CKNP glaciers since early 21st century also suggests insignificant changes in the supraglacial debris extent [20,22].…”

“…Thus, it is important to incorporate changes in the future cryosphere that are plausible under anticipated climate change scenario, while assessing the future water availability from a glacerized basin. Since the overall glacial extent of the UIB somewhat remained stagnant since 1980s [28][29][30]65] and particularly since early 21st century [20,22] under the ongoing regional warming, no change in the present-day glacial extent has been assumed for the near-future scenario (2013-2030), as also adopted by several studies [5,9,11] (Table 2). In view of obtaining a far-future climate change scenario, projections for an extreme emissions scenario of RCP 8.5 are considered for the last decade of the 21st century.…”

Climate–Glacier Dynamics and Topographic Forcing in the Karakoram Himalaya: Concepts, Issues and Research Directions

“…Given such complex geodynamics, there is an urgent need to better understand the Karakoram Anomaly [30][31][32]. To do so, we must account for a variety of controlling factors, such as climate-system interactions between the monsoon and the westerlies, climatic teleconnections (such as those produced by ENSO), the anisotropic nature of topography, and debris-load dynamics that modulate the influence of climatic variables.…”

“…The Karakoram Mountain Range in Pakistan features some of the largest glaciers on Earth outside of the Polar Regions. Most of these glaciers are heavily debris-covered and avalanche-fed, and some of them appear to be departing from the global trend of recession [27][28][29][30][31][32][33][34]. Moreover, a controversial and incorrect statement about the disappearance of Himalayan glaciers by the year Advancing glaciers and positive mass balance conditions in the Karakoram are related to the region's unique snowfall regime [61].…”