Investigation of land–atmosphere interaction at a high altitude (5330 m a.s.l.) snow covered station of East Himalaya

The land-atmosphere interaction of a topographically complex ice surface of high-altitude Yala Glacier station in the east Himalaya is studied. In the study site, shift in wind direction during October and November suggests the dominance of mountain-valley wind circulation. Tunnel effect is evident during the daytime owing to tall mountains, which affect the direction and speed of the wind flow. During the day, the snow cover evaporates and enhances the relative humidity (74%) and mixing ratio (0.005 kg kg^− 1). In October, fresh snow cover reflects maximum amount of incoming shortwave (S_inc) into space than in November. On the other hand, November’s sensible heat flux is higher than that of October, indicating that more heat is transferred from the snow surface to the atmosphere. The difference between Sin-Sout in October and November is 133 ± 63 Wm−2 and 282 ± 130 Wm−2, respectively. Compared to October, the ice cover absorbs more S_inc in November, which increased the melting of ice cover. In October and November, the mean albedo during the day is 0.80 ± 0.06 and 0.57 ± 0.09, respectively. Between 1000 and 1100 local time in October, there is a noticeable shift in the albedo, ranging from 0.5 to 0.9, which reveals that the snowmelt has altered the surface albedo. The mean climate sensitivity in October and November are 0.006 ± 0.001 ºCWm^− 2 and 0.007 ± 0.002 ºCWm^− 2, respectively. Climate sensitivity strongly correlates with day-night temperature variation (dT). It is observed that dT is negatively correlated with relative humidity, incoming longwave (L_inc), and outgoing longwave radiation (L_out) and positively correlated with wind speed, S_inc, and S_out.