Changes in seasonal snow cover in Hindu Kush-Himalayan region

Abstract

The changes in seasonal snow covered area in the Hindu Kush-Himalayan (HKH) region have been examined using Moderate – resolution Imaging Spectroradiometer (MODIS) 8-day standard snow products. The average snow covered area of the HKH region based on satellite data from 2000 to 2010 is 0.76 million km<sup>2</sup> which is 18.23% of the total geographical area of the region. The linear trend in annual snow cover from 2000 to 2010 is −1.25±1.13%. This is in consistent with earlier reported decline of the decade from 1990 to 2001. A similar trend for western, central and eastern HKH region is 8.55±1.70%, +1.66% ± 2.26% and 0.82±2.50%, respectively. The snow covered area in spring for HKH region indicates a declining trend (−1.04±0.97%). The amount of annual snowfall is correlated with annual seasonal snow cover for the western Himalaya, indicating that changes in snow cover are primarily due to interannual variations in circulation patterns. Snow cover trends over a decade were also found to vary across seasonally and the region. Snow cover trends for western HKH are positive for all seasons. In central HKH the trend is positive (+15.53±5.69%) in autumn and negative (−03.68&plusmn3.01) in winter. In eastern HKH the trend is positive in summer (+3.35±1.62%) and autumn (+7.74±5.84%). The eastern and western region of HKH has an increasing trend of 10% to 12%, while the central region has a declining trend of 12% to 14% in the decade between 2000 and 2010. Snow cover depletion curve plotted for the hydrological year 2000–2001 reveal peaks in the month of February with subsidiary peaks observed in November and December in all three regions of the HKH

The Dynamics of Land Use/Cover and the Statistical Assessment of Cropland Change Drivers in the Kabul River Basin, Afghanistan

“…Permanent snow/ice covered land and unused land were also amongst the LULC types that were more on the decline. This is in consistent with previous studies at regional and national scales [74,75]. The decreasing and increasing rates of snow/ice covered land were 1.5% and 1.3%, respectively.…”

“…There was an increase in water bodies of 1,272,013 ha (55% of 2010) against a On the other hand, the rate of decrease of forest areas (i.e., 5.8%) was about three times higher than the rate of increase (i.e., 1.6%), resulting in a decline of forest covers. The previous studies on Afghanistan's forest change also confirm the rapid rate of forest cover decrease [72][73][74]. Use of wood for fuel and heating, illegal smuggling, instability in the forest-dominant areas, weak management, and urban and cropland expansion were considered to be the main drivers of deforestation [39,71,73].…”

An analysis of snow cover changes in the Himalayan region using MODIS snow products and in-situ temperature data

“…Some studies (e.g. Gafurov and Bardossy, 2009;Gurung et al, 2011) applied different techniques for filtering cloud obscured pixels from the MODIS snow cover products. In this study, we observed that the percentage of cloud covers and its timing varies significantly at different elevation zones.…”

Black carbon aerosols over the Himalayas: direct and surface albedo forcing

“…Hence, the accurate characterisation of absorbing aerosols and spectral surface albedo is essential in understanding the regional heterogeneity of aerosol DRFs at TOA. As the annual mean snow cover accounts for only 18% of the total geographical area of the Himalayas (Gurung et al, 2011), the large heterogeneities in the surface albedos are very important in the estimation of regional climate forcings. A precise analysis of snow cover seasonality is also essential for a better understanding of the DRF over the Himalayan region.…”