Impact of changing climate on glaciohydrology in Baspa basin

Transcription

1 Impact of changing climate on glaciohydrology in Baspa basin Rajesh Kumar1*, Shaktiman Singh1, Shruti Singh1, Ramesh Kumar1, Atar Singh1, Anshuman Bhardwaj1,2 and Surjeet S. Randhawa3 1Dept. of Environmental Science, School of Basic Sciences and Research, Sharda University, India 2Division of Space Technology, Luleå University of Technology, Kiruna, Sweden 3State Council for Science, Technology and Environment, Shimla, India * Conf. on Climate and Environment Change Impact on the Indus Basin Waters ; February 16-18, 216, ICIMOD

2 Overview 1. Indian Himalayan Region Change observed in temperature Change observed in precipitation 2. Baspa basin Comparison of temperature and discharge Comparison of temperature and percentage snow cover Change in annual snowfall 3. Naradu glacier Change in temperature Annual specific mass balance Long-term change in equilibrium line altitude 4. Shaune Garang glacier Annual specific mass balance Long-term simulated monthly discharge Long-term annual melt season discharge 5. Conclusions

3 Introduction

4 Hindu Kush-Himalaya (HKH) have around 5% (by area) of all the glaciers falling outside the polar realm. The rivers originating from these mountains provide freshwater to support livelihood of people (~1.3 billion) living in densely populated downstream regions. studies propose that most of the Himalayan glaciers are retreating in general with exception to Karakoram region. Major river basins and glaciers in Hindu-Kush- Himalayas adjoining Indian Himalayas (Boundary after Bajracharya and Shrestha, 211)

5 IHR area - ~.67 million sq. km (about 2% of country s total geographical area) GSI (28) - estimated 9,575 glaciers in Indus and Ganga (including Bramputra) basins of IHR inventory by (SAC, 211), suggested around 32,392 glaciers in Indus, Ganges and Brahmaputra basins. Map of Indian Himalayan Region (IHR) showing the location of thirteen glaciers for which glaciological mass balance measurements is available for at least five years (Singh et al., 216 ; in press WIREs Climate Change)

6 Annual Specific Mass Balance (meter water equivalent per year) Area (sq. km) Mass Balance and area of glaciers in Indian Himalayan Region with observations > 5Years Nehnar Gara.5 14 Gorgarang Shaune Garang Dunagiri Tipra Bamak Chhota Shigri Dokriani Hydrological Year Hamtah Source: Kumar et al., 27; Wagnon et al., 27; Azam et al., 213; Dhobhal et al., 28; Srivastava et al., 1999; Raina et al., 1977; Ravi Shanker, 21; Singh & Sangewar, 1989; Srivastav & Swaroop, 1989; Gautam & Mukherjee, 1989

7 Zanskar glacier 1 Zanskar glacier 3 Zanskar glacier 4 Zanskar glacier 5 Zanskar glacier 6 Zanskar glacier 8 Zanskar glacier 7 Zanskar glacier 9 Zanskar glacier 1 Zanskar glacier 12 Zanskar glacier 13 Drang Drung Average Retreat (m/year) Period of observation Average retreat (meter/year) observed Average snout retreat rate m/year - Jammu & Kashmir, India Retreat rate (m/year) Period (years) Source: Kamp et al., 211; Kulkarni & Karyakarte, 214

8 Miyar Triloknath Panchi nala I Panchi nala II Beas Kund Sonapani Samudra Tapu Hamtah Jobri Chhota Shigri Sara ugma Bara Shigri Man Talai Bilare Bange Shaune Garang Janapa Garang Average Retreat (m/year) Period of observation Average retreat (meter/year) observed Average snout retreat rate m/year - Himachal Pradesh, India Retreat rate (m/year) Period (years) Source: Sangewar & Kulkarni, 211; Kulkarni et al., 26; Kulkarni & Bahuguna, 22; Kulkarni & Karyakarte, 214

9 Average Retreat (m/year) Period of observation Average retreat (meter/year) observed Average snout retreat m/year Uttarakhand, India Retreat rate (m/year) Period (years) Source: Sangewar & Kulkarni, 211; Naithani et al., 21; Kumar et al., 28; Bhambri et al., 212; Bahuguna et al., 27; Nainwal et al., 28; Cotter & Brown, 197; Tewari, 1966; Bali et al., 28; Oberoi et al., 21; Kulkarni & Karyakarte, 214

10 Fowler and Archer, 26 (1961-2) Station Data (Srinagar) Dash et al., 27 (191-23) Reanalysis Data Bhutiyani et al., 27 (191-2) Station Data Singh et al., 28 (a) (9-1 Years) Station Data Bhutiyani et al., 21 ( ) Station Data Dimri and Dash, 212 ( ) Station Data Kumar et al., 214 ( ) Reanalysis Data Dash et al., 27 (191-23) Reanalysis Data Jhajhaaria and Singh, 21 (196/7's-2) Station Data Immerzeel, 28 (191-22) Reanalysis Data Change in temperature ( C/Decade) Period of Analysis (Years) Tave Tmax Tmin Period of analysis Western IHR Eastern IHR Summary of temperature trend observed by several studies in different parts of IHR. Tave, Tmax and Tmin represent Average Temperature, Maximum Temperature and Minimum Temperature respectively. (Singh et al., 216 ; in press WIREs Climate Change)

11 Increase in extreme rainfall events Decrease in moderate rainfall events Increase in annual precipitation of J&K and other eastern Himalayan states Decrease in annual precipitation of U Khand & HP Gilgit Skardu Srinagar Kanzalwan Gulmerg Haddan Taj Leh Patseo Dhundi Solang Shimla Map of IHR showing trends of precipitation in different parts of IHR. The station data has been shown after Archer and Fowler, (24) and Bhutiyani et al., (21) and state-wise trend has been shown after Guhathakurta and Rajeevan, (28). (Singh et al., 216 ; in press WIREs Climate Change)

12 Baspa basin

13 Location map of Baspa basin with location of weather stations for which meteorological data is available for different time periods The total area of the basin is 11 sq. km with around 89 glaciers (Raina and Srivastava, 28). A tributary to Satluj River

14 Jan-85 Mar-86 May-87 Jul-88 Sep-89 Nov-9 Jan-92 Mar-93 May-94 Jul-95 Sep-96 Nov-97 Jan-99 Mar- May-1 Jul-2 Sep-3 Nov-4 Jan-6 Mar-7 May-8 Jul-9 Sep-1 Nov-11 Temperature ( C) Discharge (cu.m/sec) Average Temperature ( C) Average Discharge (cu.m/sec) Comparison of monthly discharge (at basin outlet) with mean monthly temperature (Rakchham station 313 m asl) in the basin

15 Oct-4 Dec-4 Feb-5 Apr-5 Jun-5 Aug-5 Oct-5 Dec-5 Feb-6 Apr-6 Jun-6 Aug-6 Oct-6 Dec-6 Feb-7 Apr-7 Jun-7 Aug-7 Oct-7 Dec-7 Feb-8 Apr-8 Jun-8 Average Temperature ( C) Snow Cover (%) 25 Average Temperature ( C) Snowcover average (%) Comparison of monthly snow cover % with mean monthly temperature (Rakchham station 313 m asl) in the basin

16 Naradu Glacier

17 Area: 3.7 km 2 Map of Naradu glacier showing different elevation zones

18 Temperature C Annual maximum, minimum and mean air temperature shows a rise of 1.68 C, 1.6 C and 1.62 C during the year Annual Maximum Annual Minimum y =.583x y =.568x These results are in agreement with the warming reported in Himalaya in several studies (Shrestha et al., 1999; Bhutiyani et al., 27) y =.553x Graph showing the annual maximum, minimum and mean temperature ( ) from GIOVAANI (Goddard Earth Sciences Data Information Services Center, 213), downloaded for the Naradu basin (Updated after Kumar et al., 214) Mann Kendall test along with other statistical tests like Spearman Rank Correlation (SRC) test, Sen s Slope (SS) test, Sequential Mann Kendall test (SQMK) were applied to the annual, monthly as well as on seasonal data.

19 Temperature ( C) 2.5 Tmax Tmin Tmean Winter Premonsoon Monsoon Postmonsoon Annual The rise in temperature ( ) in the reanalysis dataset from GIOVAANI(Goddard Earth Sciences Data Information Services Center, 213), downloaded for the Naradu basin and calibrated using the observed data on Naradu glacier. (Updated after Kumar et al., 214)

20 Snowfall (cm) The decrease in annual snowfall ( to ) in 2D monthly snowfall data from GIOVAANI, (Goddard Earth Sciences Data Information Services Center, 213), downloaded for the Naradu basin

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22 Annual specific mass balance (m w.e.) Hydrological Year Graph showing the annual specific mass balance (m w.e.) of Naradu Glacier during 2-1 to 22-3 (Koul and Ganjoo, 21) and to

23 Equilibrium Line Altitude (m asl) Increase in Equilibrium Line Altitude (ELA) (m a.s.l) of Naradu Glacier estimated using multiple linear regression between temperature and precipitation (independent) and ELA (dependent) for which field data of ELA from 21-3 (Ganjoo et al., 21) and has been used.

24 Shaune Garang Glacier

25 Map showing location of Shaune Garang Catchment, the study area and glaciated area in the catchment (Landsat 8, 2 th August, 214) with location of stations and discharge gauge Situated in the Pir Panjal range of Western Himalaya. Influenced by westerlies and monsoon Contributes its discharge to the Baspa river which is a tributary to the Satluj river.

26 Altitude range (m) The total area= 6 km 2. Area of the catchment above discharge gauge (3963 m asl) is km 2, Shaune Garang glacier= 4.94 km 2 Debris-free Glaciated area Debris-Covered Glaciated area Non - Glaciated Area > Area (sq. km) Hypsometric distribution of land cover for Shaune Garang catchment above discharge gauge (mapped on Landsat 8 image acquired on 2th August, 214)

27 Annual specific mass balance (m w.e.) Discharge (million cu.m/day) Annual specific mass balance (m w.e.) Average annual melt season discharge (million cu. m/day) Hydrological Year Graph showing annual specific mass balance (m w.e.) and average annual melt season discharge (million cubic meters per day) of Shaune Garang glacier (Data source: Raina and Srivastava, 28)

28 Basin Area Temperature Precipitation Glacier Free Area Discharge from glacier free area Estimation of losses Debris Covered Ice area Glaciated Area Debris Free Ice area Temperature Index Model Total Melt Snow Covered area Altitudinal Interpolation Form of Precipitation Input Temperature Degree Day Factor (mm C -1 Day -1 ) Total Discharge Schematic flow diagram of temperature index based glacio-hydrological model used in the study

29 11/7/214 18/7/214 25/7/214 1/8/214 8/8/214 15/8/214 22/8/214 29/8/214 5/9/214 12/9/214 19/9/214 Simulated discharge/observed Discharge/ Precipitation (mm) Temperature (mm) 35 Simulated Discharge (mm) Precipitation (mm) Observed Discharge (mm) Temperature ( C) Comparison of observed discharge and simulated discharge with mean daily temperature and daily total precipitation during the validation period (11 th July, 214 to 25 th August, 214)

30 Simulated Discharge (cu.m/sec) y =.7747x R² = VALIDATION OF MODEL S performance Observed Discharge (cu.m/sec) Comparison of observed and simulated discharge in the basin for the validation period (11 th July, 214 to 25 th August, 214)

31 Average monthly discharge (m 3 sec -1 ) Jan/85 Jan/86 Jan/87 Jan/88 Jan/89 Jan/9 Jan/91 Jan/92 Jan/93 Jan/94 Jan/95 Jan/96 Comparison of monthly simulated discharge (using degree day model ) with mean monthly temperature observed at 313 m asl near the basin for period of simulation (January 1985 to December 27) Jan/97 Jan/98 Jan/99 Jan/ Jan/1 Jan/2 Jan/3 Jan/4 Jan/5 Jan/6 Jan/7 Average monthly temperature ( C) 12 1 Simulated Discharge Temperature (313 meter) Linear (Simulated Discharge) y = -4E-5x

32 Discharge (cu.m/sec) Comparison of simulated and observed average melt season (May-October) discharge and net annual mass balance of Shaune Garang Glacier. The data of observed melt season discharge and net mass balance have been represented after Raina and Srivastava, 28. Mass Balance (m w.e.) Net Mass Balance Simulated Discharge Observed Discharge Linear (Simulated Discharge) y = -.245x

33 Discharge (cu.m/sec) 9 8 Ice Snow Rain and Base Flow Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec The average contribution of different components in total stream flow of the basin during simulation period (January 1985 to December 27)

34 Conclusions The climate change signals on glacial environment of IHR - increasing temperature trend. The rate of warming is higher in recent decades. The reanalysis temperature data suggest rise in the average temperatures maximum (.58 C/decade) and minimum (.55 C/decade) in Naradu basin ( ) while maximum (.59 C/decade) and minimum (.68 C/decade) for (Kumar et al, 214) The impact of warming is evident on form of precipitation in Baspa basin through annual snowfall reduction by 21 cm/decade. Negative mass balance on Naradu and Shaune Garang glaciers in Baspa basin. Continuous increase in ELA (total 112 m during ) The simulated long term discharge for Shaune Garang glacier shows slight decreasing trend which is mainly attributed by decreasing glacierised area in the catchment.

35 Conclusions Average snout retreat rate in Jammu and Kashmir, Himachal Pradesh and Uttarakhand is 17.25, and m/year respectively. Average specific mass balance of all the glaciers in Indian Himalayan Region with observed data > 5 Years was found to be -.6 meter w.e. per year. The snow cover, discharge and average temperature in Baspa Basin shows strong correlation. The studies and data available for Indian Himalayan Region is in parts and for smaller periods to many locations; hence not enough to get any conclusion with high confidence regarding impacts of changing climate. But some of the mountain disasters (recently in Uttrakhand) and extreme weather events like torrential rainfall in small pockets are a kind of visible sign of changing climate. Hence it is important to carry out more studies on long term mission rather than a smaller project mode and also promote data sharing for better results.

36 Acknowledgements All the people working in high altitudes who have contributed to the database represented here. Department of Science and Technology (DST), Govt. of India for funding project on Naradu Glacier. United States Agency for international Development (USAID) for funding project on Shaune Garang Glacier entitled Contribution to High Asia Runoff from Ice and Snow (CHARIS) Bhakhra Beas Management Board (BBMB), India Meteorology Department (IMD), Govt. of India and Dr. Hendrik Wulf, Dept. of Geography, University of Zürich, Switzerland for providing meteorological data used in the study. International Centre for Integrated Mountain Development (ICIMOD) for inviting to present this talk. Our co-workers (Porters, Mountaineering Agencies) helping in extreme weather condition and harsh terrain to create database for developing knowledge and better understanding for sustainable environment.

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