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1 Introduction
The majority of mountain glaciers, including those from the Himalaya, are experiencing an accelerated recession during the last few decades. Changes in glaciers and
ice caps provide some of the clearest evidence of climate change, and as such, they
constitute key variables for early detection strategies in the global climate-related
observations. These changes have impacts on global sea level fluctuations, the
regional to local natural hazard situation, as well as on societies dependent on glacier meltwater (Zemp et al. 2008).
Glaciers also act to buffer short-term changes by providing a steady, reliable
source of sustenance, even in periods of reduced precipitation (Ren et al. 2006).
Since the highest ablation and the Indian Summer Monsoon (ISM) happen almost
simultaneously, the high discharge in the rivers downstream often leads to floods
whereas during winters the discharge reduces considerably due to little contribution
from snow and glaciers.
The Himalayan glaciers are considered as water towers of Asia (Immerzeel et al.
2010) as snow and glacial melt waters make an important contribution to the drinking water, agriculture, and hydropower supply of densely populated regions in
South and Central Asia (Scherler et al. 2011; Barnett et al. 2005; Bookhagen and
Burbank 2010). These water resources are very important for a country like India
where the agriculture and allied activities play a dominant role in the economy.
Measurement of runoff from a glacier melt assumes considerable importance in
understanding the influence of microclimatic parameters on the glacier melt and its
role in generation of consequential melt runoff. In order to understand the process
of generation of glacier melt from the glacier and its appearance at the snout, glacier
discharge measurements were undertaken, during part of the ablation season, on
Hamtah glacier, Lahaul & Spiti district, Himachal Pradesh (Table 1). In this paper,
we present glacier meltwater discharge characteristics of Hamtah glacier, from July
to September, the role of glacier ablation and meteorological parameters including
storage characteristics of the glacier.
2 Study Area
Hamtah (5Q212 12 180), is a northwesterly flowing small valley glacier which lies
in Chandra fifth order basin (5Q212 12), of fourth order Chenab basin (Sangewar
and Shukla 2009), covering part of the Lahaul & Spiti district of Himachal Pradesh
(Fig. 1). Originating at an elevation of ~5000 m above sea level (asl), 6.0 km long
Hamtah glacier has an average width of 0.50 km and covers an area of about 3.3 sq
km. The glacier descends with a gentle gradient and terminates at ~4000 m asl
(Shukla et al. 2015). The glacier has a large ablation zone covered with thick blanket
of supra-glacial moraines. It is known that the precipitation in the catchment area of
Hamtah glacier is controlled by Indian Summer Monsoon (ISM) in summer and by
S. P. Shukla et al.
1 Introduction
The majority of mountain glaciers, including those from the Himalaya, are experiencing an accelerated recession during the last few decades. Changes in glaciers and
ice caps provide some of the clearest evidence of climate change, and as such, they
constitute key variables for early detection strategies in the global climate-related
observations. These changes have impacts on global sea level fluctuations, the
regional to local natural hazard situation, as well as on societies dependent on glacier meltwater (Zemp et al. 2008).
Glaciers also act to buffer short-term changes by providing a steady, reliable
source of sustenance, even in periods of reduced precipitation (Ren et al. 2006).
Since the highest ablation and the Indian Summer Monsoon (ISM) happen almost
simultaneously, the high discharge in the rivers downstream often leads to floods
whereas during winters the discharge reduces considerably due to little contribution
from snow and glaciers.
The Himalayan glaciers are considered as water towers of Asia (Immerzeel et al.
2010) as snow and glacial melt waters make an important contribution to the drinking water, agriculture, and hydropower supply of densely populated regions in
South and Central Asia (Scherler et al. 2011; Barnett et al. 2005; Bookhagen and
Burbank 2010). These water resources are very important for a country like India
where the agriculture and allied activities play a dominant role in the economy.
Measurement of runoff from a glacier melt assumes considerable importance in
understanding the influence of microclimatic parameters on the glacier melt and its
role in generation of consequential melt runoff. In order to understand the process
of generation of glacier melt from the glacier and its appearance at the snout, glacier
discharge measurements were undertaken, during part of the ablation season, on
Hamtah glacier, Lahaul & Spiti district, Himachal Pradesh (Table 1). In this paper,
we present glacier meltwater discharge characteristics of Hamtah glacier, from July
to September, the role of glacier ablation and meteorological parameters including
storage characteristics of the glacier.
2 Study Area
Hamtah (5Q212 12 180), is a northwesterly flowing small valley glacier which lies
in Chandra fifth order basin (5Q212 12), of fourth order Chenab basin (Sangewar
and Shukla 2009), covering part of the Lahaul & Spiti district of Himachal Pradesh
(Fig. 1). Originating at an elevation of ~5000 m above sea level (asl), 6.0 km long
Hamtah glacier has an average width of 0.50 km and covers an area of about 3.3 sq
km. The glacier descends with a gentle gradient and terminates at ~4000 m asl
(Shukla et al. 2015). The glacier has a large ablation zone covered with thick blanket
of supra-glacial moraines. It is known that the precipitation in the catchment area of
Hamtah glacier is controlled by Indian Summer Monsoon (ISM) in summer and by
S. P. Shukla et al.