Jour. Ind. Geol. Cong., Vol.4(1), May 2012, pp.125-128. Meteorological observations at Chorabari and Dokriani glaciers, Garhwal Himalaya, India Kapil Kesarwani*, Bhanu Pratap, Rakesh Bhambri, Manish Mehta, Amit Kumar, Indira Karakoti, Akshay Verma & D.P. Dobhal* Centre for Glaciology, Wadia Institute of Himalayan Geology, Dehradun - 248 001 *Emails : kapilcfg@gmail.com, dpdobhal@wihg.res.in Abstract : Meteorological observations and characteristics of daily meteorological variables were carried out in the Chorabari (30°41’- 30°48’N and 79°1’-79°6’E) and Dokriani (30°49'-30°52’N and 78°47'-78°51’E) glaciers, Garhwal Himalaya since October, 2011. A network of three sets of Automatic Weather Stations (AWS) (Campbell Scientific) in Chorabari Glacier and three in Dokriani Glaciers were established at different altitudes to collect the meteorological parameters at hourly basis for round the year viz. air temperature, wind speed and direction, relative humidity, vapour pressure, sun duration, net radiation, albedo, precipitation and snow surface temperature. We now compare the changes in surface air temperature on both the glaciers as 65% of Chorabari Glacier ablation area is covered with debris whereas 20-25% ablation area of Dokriani Glacier is debris covered. It has been well-recognized that the albedo in the debris covered area was lower than the debris free area. To understand the macro-variability in prevailing weather a comparisons of meteorological parameters for both the glaciers were made. Characteristics of seasonal and diurnal variations of meteorological elements were also examined. The air temperature in the debris-covered area is higher than that in the debris free area. It is found that the wind speed (3-5 m/s) in the winter is more than in the summer (2-3 m/s). However, the rainfall recorded for both of the glaciers is more or less same and measured between 1200 and 1350 mm. The observation of different meteorological parameters in different glaciers and there variability at macro-scale has been analyzed and the preliminary result discussed in this paper. INTRODUCTION The Southern slope of the Himalaya (Indian part) is dependent on monsoon rains together with snow and glacier melt, to supply life-sustaining water to one of the world’s most densely populated areas (Dhar et al., 2006). Here, we provide the meteorological conditions which affect the mass balance of glaciers and a consequence, the availability of water in the downstream regions. A long-term time series of meteorological observations thus proves fundamental in the study of glacier fluctuation as a response to global climate change (Bollasina et al., 2002). Meteorological variables (precipitation, air temperature and wind speed) and their interaction with glaciers are the main factors that can control the development of glacier (Pellicciotti et al., 2011). Glacier accumulation depends on the amount of precipitation, whereas ablation depends upon the air temperature (Paterson, 1994). Therefore, a continuous collection of meteorological parameters is essential to know the impact of variation in air temperature and precipitation on the glacier health. To fulfill this objective, meteorological observations and characteristics of daily meteorological variables were carried out in Chorabari (30°41’-30°48’N and 79°1’-79°6’E) and Dokriani (30°49'- 30°52'N and 78°47'-78°51’E) glaciers, Garhwal Himalaya since October, 2011 (Fig.1). METHODOLOGY A network of three Automatic Weather Stations (AWS) (Campbell Scientific) in Chorabari Glacier, Mandakini basin and three in Dokriani Glacier, Bhagirathi basin were established at different altitudes to collect the meteorological parameters at hourly basis round the year (Fig.1). Air temperature, wind speed, wind direction, relative humidity, vapour pressure, sun shine duration, net radiation, albedo, precipitation and snow surface temperature are being continuously monitored since October 2011. The meteorological elements and instruments are summarised in Table 1. RESULTS The average wind speed was recorded 1.4 ms -1 for Chorabari Glacier and 2.0 ms -1 for Dokriani Glacier (Fig.2). The minimum temperature was recorded -14.2°C and -15.4°C for Chorabari and Dokriani glaciers, respectively. Similarly, maximum air temperature was recorded 7.1°C for Chorabari Glacier and 6.9°C for