Lok Sabha Question No. 5528 (UNSTARRED), answered on 2022-04-06
Subject: Melting of Himalayan Glaciers
Ministry: EARTH SCIENCES
Asked by: Debasree Chaudhuri

## GOVERNMENT OF INDIA MINISTRY OF EARTH SCIENCES LOK SABHA UNSTARRED QUESTION NO. 5528

## TO BE ANSWERED ON WEDNESDAY, 6 TH  APRIL, 2022

## MELTING OF HIMALAYAN GLACIERS

## 5528.  MS. DEBASREE CHAUDHURI:

Will the Minister of EARTH SCIENCES be pleased to state:

- (a) whether the Government has any data or has conducted any study on the rate at which  the glaciers in Indian Himalayan region are melting;
- (b) if so, the details thereof and if not, the reasons therefore;
- (c) whether the Government has done any assessment on the impact of increase in the melting rate of glaciers on the lives of the people in the adjoining States;
- (d) if so, the details thereof;
- (e) whether the Government has taken any action to mitigate such natural calamities; and
- (f) if so, the details thereof and if not, the reasons therefore?

## ANSWER

## THE MINISTER OF STATE (INDEPENDENT CHARGE) FOR MINISTRY OF SCIENCE AND TECHNOLOGY AND EARTH SCIENCES (DR. JITENDRA SINGH)

- (a) Yes,  Sir.  The  government  has  carried  out  studies  and  maintains  data  regarding  melting  of glaciers in the Indian Himalayan region.
- (b) Several Indian institutes/universities/organizations (Geological Survey of India (GSI), Wadia Institute  of  Himalayan  Geology(WIHG),  National  Centre  for  Polar  and  Ocean  Research (NCPOR), National Institute of Hydrology(NIH), Space Application Centre (SAC), Indian Institute  of  Science  (IISc)  etc.)  monitor  Himalayan  glaciers  for  various  scientific  studies including glacier melting  and have  reported  accelerated  heterogeneous  mass loss in Himalayan glaciers.The mean retreat rate of Hindu Kush Himalayan glaciers is 14.9 ± 15.1 meter/annum (m/a); which varies from 12.7 ± 13.2 m/a in Indus, 15.5 ± 14.4 m/a in Ganga and 20.2 ± 19.7 m/a in Brahmaputra river basins. However, glaciers in the Karakoram region have  shown  comparatively  minor  length  change  (-1.37  ±  22.8  m/a),  indicating  the  stable conditions.

Ministry of Earth Sciences (MoES) through its center National Centre for Polar and Ocean Research (NCPOR) has been monitoring six glaciers in the Chandra basin (2437km 2 area) in western Himalaya since 2013. A state-of-the-art field research station 'Himansh' established in Chandra basin and operational since 2016 for conducting field experiment and expeditions to glaciers. The rate of annual mass balance (melting) ranging from  -0.3±0.06 meter water equivalent per year (m  w.e.y -1 )to -1.13±0.22mw.e.y -1 during 2013-2020  is observed. Similarly, a mean thinning of ~50±11 m with a mean annual mass loss of -1.09± 0.32 mw.e. a -1 was observed for the Baspa basin during 2000-2011.

GSI has conducted studies on melting of the glaciers by assessment of mass balance on nine glaciers  and  also  carried  out  monitoring  the  recession/  advancement  of  76  glaciers  in Himalayan  region.  Majority  of  Himalayan  glaciers  are  observed  melting/  retreating  at varying rates in different regions.

Department  of  Science  and  Technology  (DST)  has  supported  various  R&D  projects  for studying Himalayan  Glaciers under the National Mission for Sustaining  Himalayan Ecosystem  (NMSHE)  and  National  Mission  on  Strategic  Knowledge  for  Climate  Change (NMSKCC).  The  mass  balance  studies  conducted for some  Himalayan  glaciers by University  of  Kashmir,  Sikkim  University,  IISc  and  WIHG,  revealed  that  majority  of Himalayan glaciers are melting or retreating at varying rates.

WIHG is monitoring a few glaciers in Uttarakhand, which reveal that the Dokriani Glacier in the Bhagirathi basin is retreating at 15-20 m/a since 1995, whereas Chorabari Glacier in the Mandakini  basin  is  retreating  at  9-11  m/a  during  2003-2017.  WIHG  is  also  monitoring Durung-Drung and Pensilungpa glaciers  in Suru basin, Ladakh, which are retreating at 12 m/a and ~ 5.6 m/a, respectively.

NIH  has  been  conducting  several  studies  for  the  assessment  of  runoff  from  melting  of glaciers at catchment and basin scales across Himalaya.

- (c) Yes Sir.
- (d) Melting  glaciers  have  significant  impact  on  water  resources  of  Himalayan  rivers  due  to change in glacier basin hydrology, downstream water budget, impact on hydropower plants due  to  variation  in  discharge,  flash  flood  and  sedimentation.  They  also  increase  in  risk related to glacier hazards due to enhanced number and volume of glacier lakes, accelerated flash  flood  and  Glacial  Lake  Outburst  Floods  (GLOFs),  impact  on  agro  practices  in  high Himalayan region etc.

Divecha Centre for Climate Change, IISc Bangalore under the aegis of DST has investigated Satluj  River  basin  and  reported  that  there  will  be  an  increase  in  glacier  melt  contribution until  the  middle  of  the  century  and  then  there  will  be  a  decline.  Numerous  small  glaciers located in the low altitude region of the Satluj basin indicate significant loss in the area till the middle of the century, creating a scarcity of water during the dry summer season.

- (e) Yes, Sir.
- (f) The melting of glaciers is a natural process and cannot be controlled. However, melting of glaciers  does  increase  the  risks  related  to  glacier  hazards.    Various  Indian  institutes, organizations  and universities  are  monitoring  the  Himalayan  glaciers  using  remote  sensing data at large scale to assess the calamities associated with the melting. Recently, the National Disaster  Management  Authority  (NDMA)  in  collaboration  with  the  Swiss  Development Corporation (SDC), prepared the Guidelines, Compendium and Summary for Policy Makers on the management of the Glacial Lake Outburst Floods (GLOFs).

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