Investigating the Performance of Snowmelt Runoff Model Using Temporally Varying Near-Surface Lapse Rate in Western Himalayas

Abstract

The present study assesses the effect of accounting the temporal variation of near-surface lapse rate in the conceptual, degree-day snowmelt runoff model simulations in a cold-desert region of Himalayas. The nearsurface lapse rate over Spiti basin shows seasonal variation during a year. The results obtained show that the inclusion of monthly variation of lapse rate in the hydrological modelling is able to capture the observed hydrograph more efficiently than when an annually constant value of lapse rate is employed. Based on our results and considering the available data, a monthly representation of near-surface lapse rates in the temperature index based models is recommended for Himalayan basins.

Maximum and minimum air temperature lapse rates in the Andean region of Ecuador and Peru

“…This stresses that the use of a fixed MELR (i.e., −6.5°C·km −1 ) might lead to gross errors (i.e., slightly during the wet season and strongly in the dry season). A similar finding in relation to MELR has been confirmed in previous studies (e.g., Hubbart et al ., 2007; Blandford et al ., 2008; Gardner et al ., 2009; Minder et al ., 2010; Kulshrestha and Ramsankaran, 2018). All these studies (located in Rocky Mountains, Arctic or Western Himalayas) showed different values (generally weaker) than −6.5°C·km −1 .…”

“…In hydroclimatic research, it is common to apply elevation‐dependent LRs to interpolate air temperature. As such, they have been widely applied in various disciplines, such as glaciology, hydrology and ecology (Immerzeel et al ., 2014; Hanna et al ., 2017; Kulshrestha and Ramsankaran, 2018). Among them, the most used LR is the fixed Mean Environmental Lapse Rate (hereafter MELR: −6.5°C·km −1 ), which assumes free atmospheric conditions (Barry and Chorley, 2003).…”

Estimation of Snow Depletion Curve for Gangotri Basin Using Multi-Source Remote Sensing Data

“…SCA of a glacier plays a key role in estimating and forecasting daily stream flow for a mountainous basin where snow melt is an important runoff factor. Several studies have utilized satellite data for runoff analysis by estimating SCA for different glaciers worldwide (Immerzeel et al, 2009;Aggarwal et al, 2014;Tiwari et al, 2015;Firouzi and Sadeghian, 2016;Steele et al, 2017;Kulshrestha et al, 2018). Immerzeel et al, (2009) used snow cover products available from Moderate Resolution Imaging Spectroradiometer (MODIS) for large scale monitoring of snow cover and simulation of runoff for Himalayan river basins comprising of Indus, Irrawaddy, Ganges, Salween, Brahmaputra, Yangtze, Yellow and Mekong from 2000 to 2008.…”

“…Steele et al, (2017) used MODIS snow products for simulating snowmelt runoff for Upper Rio Grande headwater basin in Colorado from 2001 to 2011. Kulshrestha et al, (2018) studied the effect of temporal variation in near surface lapse rate on degree-day SRM for cold desert region of Spiti river basin in Himalayas by utilizing MODIS Terra 8-day MOD10A2 dataset for 2001, 2002, 2004 and 2005. Hence, monitoring of SCA on a regular interval can be carried out by using satellite data for generation of SDC for the glacier. Due to fixed temporal resolution of a satellite, SCA is estimated only on a periodical time interval.…”