235
ism in the area makes room for more vehicular inputs/burning of fossil fuels thereby
increasing the concentration of GHGs in the area which increase the temperature of
the region. It was reported by Bhutiyani (2016) that observatories lying on windward side of Pir Panjal, Great Himalayan range and Karakoram Range have experienced comparatively more warming than those lying on leeward side. They also
reported that annual precipitation and monsoonal rainfall showed declining trend.
Interestingly, maximum decline in annual precipitation was also reported for LH by
ERA-I. However, rate of decline was found to be lesser during 2001–2015 than that
during 1985–2000.
The declining temperature trends and reduced rate of declining precipitation
since 2000 are totally out of phase with warming trends observed elsewhere. Thus,
we attempted to validate these climatic trends with snow cover area (SCA) changes
pre and post year 2000 since temperature and precipitation fluctuations are reflected
in SCA faster than changes in glacier area because of variable response time of
glaciers (more for large glaciers and vice versa). The advent of advanced satellitedriven products with better resolution has led to increase in SCA studies on
Himalayas especially after 2000. Few studies from available literature show coherence to these declining temperature trends by reporting increased wintertime snow
cover area in westerly dominated areas since 2000 (Immerzeel et al. 2009; Hasson
et al. 2014; Wang et al. 2015; Tahir et al. 2016). In addition, Singh et al. (2014)
reported increasing snow cover area (SCA) trend during 2000–2011 for Indus
Basin. Since Indus basin encompasses majority of NWH, the increasing trend in
SCA is in agreement with declining temperature/reduced rate of warming post 2000
as depicted by both ERA-I and CRU-TS. The warming over KH during same period
as observed and estimated by CRU-TS and ERA-I wouldn’t have made significant
impact due to prevalence of sub-zero temperatures over KH round the year.
Long term studies on glacier retreat in Western and Karakoram Himalaya depict
significant loss in glacier area before year 2001 (Azam et al. 2018, TableS-3). But
few recent studies conducted for shorter durations especially after year 2001
reported steady state of glaciers compared to rate of retreat prior to 2001 (Bahuguna
and Rathore 2014). Though the response of glaciers towards changing climate is not
that immediate, but the impacts are surely reflected by smaller glaciers. Such findings about varying rate of glacier retreat pre and post 2000 fortifies the utility of
ERA-I and CRU-TS in precisely capturing short term climatic changes.
Apart from SCA, mass budget of a glacier is also considered sensitive indicator
of climatic changes. Ironically, mass budget assessment studies are not available on
annual basis which if exist doesn’t span a longer duration thereby constraining our
crisp understanding about linkages between climate and glacier mass budget.
However, a review study by Azam et al. 2018 discussed about annual mass budget
of Chhota Shigri glacier (benchmark glacier in Greater Himalayan region) during
2003–2014. One can observe that though overall mass budget of glacier during
2003–2014 indicates a mass loss condition, hitherto the rate of mass loss magnitude
has shifted from more negative values towards less negative values and slight positive (2005, 2010, and 2011) during recent years. Temperature cooling and rise in
precipitation(CRU-TS)/decline (ERA-I) in rate of precipitation decline over GH
An Appraisal of Spatio-Temporal Characteristics of Temperature and Precipitation…
ism in the area makes room for more vehicular inputs/burning of fossil fuels thereby
increasing the concentration of GHGs in the area which increase the temperature of
the region. It was reported by Bhutiyani (2016) that observatories lying on windward side of Pir Panjal, Great Himalayan range and Karakoram Range have experienced comparatively more warming than those lying on leeward side. They also
reported that annual precipitation and monsoonal rainfall showed declining trend.
Interestingly, maximum decline in annual precipitation was also reported for LH by
ERA-I. However, rate of decline was found to be lesser during 2001–2015 than that
during 1985–2000.
The declining temperature trends and reduced rate of declining precipitation
since 2000 are totally out of phase with warming trends observed elsewhere. Thus,
we attempted to validate these climatic trends with snow cover area (SCA) changes
pre and post year 2000 since temperature and precipitation fluctuations are reflected
in SCA faster than changes in glacier area because of variable response time of
glaciers (more for large glaciers and vice versa). The advent of advanced satellitedriven products with better resolution has led to increase in SCA studies on
Himalayas especially after 2000. Few studies from available literature show coherence to these declining temperature trends by reporting increased wintertime snow
cover area in westerly dominated areas since 2000 (Immerzeel et al. 2009; Hasson
et al. 2014; Wang et al. 2015; Tahir et al. 2016). In addition, Singh et al. (2014)
reported increasing snow cover area (SCA) trend during 2000–2011 for Indus
Basin. Since Indus basin encompasses majority of NWH, the increasing trend in
SCA is in agreement with declining temperature/reduced rate of warming post 2000
as depicted by both ERA-I and CRU-TS. The warming over KH during same period
as observed and estimated by CRU-TS and ERA-I wouldn’t have made significant
impact due to prevalence of sub-zero temperatures over KH round the year.
Long term studies on glacier retreat in Western and Karakoram Himalaya depict
significant loss in glacier area before year 2001 (Azam et al. 2018, TableS-3). But
few recent studies conducted for shorter durations especially after year 2001
reported steady state of glaciers compared to rate of retreat prior to 2001 (Bahuguna
and Rathore 2014). Though the response of glaciers towards changing climate is not
that immediate, but the impacts are surely reflected by smaller glaciers. Such findings about varying rate of glacier retreat pre and post 2000 fortifies the utility of
ERA-I and CRU-TS in precisely capturing short term climatic changes.
Apart from SCA, mass budget of a glacier is also considered sensitive indicator
of climatic changes. Ironically, mass budget assessment studies are not available on
annual basis which if exist doesn’t span a longer duration thereby constraining our
crisp understanding about linkages between climate and glacier mass budget.
However, a review study by Azam et al. 2018 discussed about annual mass budget
of Chhota Shigri glacier (benchmark glacier in Greater Himalayan region) during
2003–2014. One can observe that though overall mass budget of glacier during
2003–2014 indicates a mass loss condition, hitherto the rate of mass loss magnitude
has shifted from more negative values towards less negative values and slight positive (2005, 2010, and 2011) during recent years. Temperature cooling and rise in
precipitation(CRU-TS)/decline (ERA-I) in rate of precipitation decline over GH
An Appraisal of Spatio-Temporal Characteristics of Temperature and Precipitation…