Role of Elevation and Aspect in Snow Distribution in Western Himalaya

Abstract

Snow is a dynamic natural element, the distribution of which is largely controlled by latitude and altitude. In the tropical country like India, snow distribution is mostly controlled by altitude. The present study aims to identify the relationship between snow accumulation with elevation and aspect in rugged terrain in the Himalayan region. The river basins of four tributaries of the River Indus i.e. Satluj, Chenab, Ravi and Beas located in the western Himalaya were considered for study. Snow covered area was estimated for a period of 2 years (01 Jan 2003 to 17 Dec 2004) using MODIS 8 days' maximum snow cover products. Aspect and classified relief maps were prepared using the USGS DEM. The interrelationship between aspect, elevation and snow cover area was determined for all the four river basins and comparative analysis has been made. A 2 years average shows that Satluj has the minimum snow covered area 23%, while Chenab has the highest snow covered area i.e. 42%, Ravi and Beas has 33% and 38% respectively. The minimum elevation from where snow covered area appears has been calculated and it has been observed that in case of Satluj, snow appears at a higher elevation (1,369 m) while in Chenab snow appears at an elevation of 834 m, followed by Ravi (1,058 m) and Beas (1,264 m). It was found that aspect has a major impact on snow accumulation in the lower elevations in all the basins as compared to higher elevations. Snow accumulates most in the northwest and northeast aspect. The rate of change in snow cover with elevation is determined for all the river basins and it has been concluded that Satluj has the lowest rate of change of snow cover with elevation (1.3% per 100 m), Chenab 1.8% per 100 m, followed by Ravi 2% per 100 m and Beas (2% per 100 m).

Assessment of temporal dynamics of snow cover and its validation with hydro-meteorological data in parts of Chenab Basin, western Himalayas

“…To examine in which season the air temperature decreased most, the data set was divided into four seasons: winter (December to March), pre-monsoon (April to June), monsoon (July to September), and post-monsoon (October to November) Jain et al, 2009). Thus, in the study we represent the winter, pre-monsoon, monsoon and post-monsoon seasons by considering the average of mean air temperature during the months of December to March, April to June, July to September and October to November, respectively, of each year.…”

Climate and topographic controls on snow cover dynamics in the Hindu Kush Himalaya

“…Although much is at stake, our understanding of the spatial variability of snow accumulation and melt (altitude, east to west) is limited by a lack of research on an appropriate scale in the HKH region. The bulk of these studies have a regional to sub-regional focus (Zhang et al, 2004;Dahe et al, 2006;Li et al 2008;Zhang et al, 2010;Gurung et al 2011b;Maskey et al, 2011;Jin et al, 2015;Singh et al, 2014), and catchment level research is even more sparse (Jain et al, 2009;Kulkarni et al, 2010;Sharma et al, 2012).…”

Effect of Climate Change on Potential Evapotranspiration in the Upper Beas Basin of the Western Indian Himalaya

“…Thalout station discharge data for the period 1971-2002 was taken from the Ghorpa hydel project report for SWAT model calibration and validation. Seasonal analysis of PET in the study was also carried out by adopting a classification of seasons, namely winter (Dec-March), pre-monsoon (April-June), monsoon (July-Sep) and post-monsoon (Oct-Nov) (Jain et al, 2009).…”