Monitoring of Mountain Glacial Variations in Northern Pakistan, from 1992 to 2008 using Landsat and ALOS Data. R. Jilani, M.Haq, A.

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1 Monitoring of Mountain Glacial Variations in Northern Pakistan, from 1992 to 2008 using Landsat and ALOS Data R. Jilani, M.Haq, A. Naseer Pakistan Space & Upper Atmosphere Research Commission (SUPARCO) SUPARCO HQs, Sector-28, Gulzar-e-Hijri off University Road, Karachi-75270, Pakistan PI # 351 Abstract Glacier changes, especially recent melting, can affect our resources including drinking water supplies, agriculture, hydroelectric power, transportation, tourism, coastlines, and ecological habitats. Glacial changes can also have a more immediate impact on communities that rely on glaciers for their water supply, or on regions susceptible to floods, avalanches, or landslides triggered by abrupt glacial melt. Monitoring of glaciers for estimation of glaciated area is felt essential. Satellite data can be effectively used for such monitoring, where the area is vast and in accessible. Multi temporal data will help in estimation of future changes in glaciated area and also track size and movement of glaciers. In continuation to previous study ( A Study of Glaciers in Northern Pakistan published in proceeding of ALOS First Joint PI Symposium of ALOS Data Nodes for ALOS Science Program in Kyoto), the study has been extended to monitor Ghulkin and Passu Glaciers, situated in the south of Batura Glacier, these glaciers have experienced GLOF on 21 May 2008, causing massive damage to houses and crops and blocked Karakoram Highway. The purpose of this study is to analyze the variations in Ghulkin and Passu Glaciers during 1992 and Analyses of Batura, Biafo, Yazghil and Jutmau have also been included in the study. Landsat (TM Oct 1992, ETM+ Oct 2000) and ALOS (AVNIR Oct 2007) cloud free images were selected for the study. Spectral signatures of glaciated, non glaciated and transition (mixed snow & ice) areas have been identified using supervised, unsupervised and band ratios techniques. The glaciers retreat in the region is due to global warming. Keyword: Ghulkin Glacier, Passu Glacier, ALOS (AVNIR), GLOF, Global Warming Introduction Glaciers serve as the largest source of fresh water on Earth. Pakistan is blessed by nature with abundance of fresh water stored in the form of snow. Assessment of snow cover area of Batura and Biafo Glaciers situated in Northern Pakistan was made, indicating significant decrease in snow cover area [1]. Present study aims at analysis of the situation in Yazghil, Jutmau, Ghulkin and Passu Glaciers. Global Warming Effects on Glaciers Due to greenhouse effect absorption and emission of infrared radiation by atmospheric gases, warm planet's atmosphere and surface. Observations of NASA s Goddard Institute for Space Studies which come from the global series indicate continuous trend of rising global temperatures (Fig. 1). The average temperature of C in the 1970s rose to C in the 1980s. In the 1990s it reached C. And during the first five years of this new decade, it has averaged C. Figure 1: Global temperature (ºC) trend

2 According to UNDP, the global warming in the Himalayas region is causing retreat of glaciers to an average rate of 30 to 60 meters per decades [7]. Fig.2 shows mean temperature trend from 1901 to 2000 for Pakistan. The average temperature of 20 C in the 1901s rose to 21.2 C in the 2000s. The increasing trend in temperature is about 0.6 C which is a clear evidence of temperature rise in Pakistan. Glaciers in Himalayas are receding faster than in any other part of the world and, if the present rate continues, the likelihood of their disappearing by the year 2035 is very high [8]. The study area lies in Gilgit and Baltistan in FANA Province of Pakistan. Its position is between latitude 35º 16-37º 05 N, longitude 74º 02-76º 53 E. Data Landsat TM and ETM+ images were obtained from Earth Science Data Interface (ESDI) and accessed from AVNIR images were acquired from ALOS User Interface Gateway (AUIG) and accessed from Methodology Temperature ºC Source: GCISC Following algorithms have been adopted for identifying snow cover and snow free pixels from Landsat TM & ETM+ and ALOS AVNIR images. Therefore in order to completely identify a snow cover pixels we have used the following methodologies: Year Figure 2: Mean Temperature (ºC) trend for Pakistan Study Area 1. Extraction of the study area from the satellite data 2. Interpreting the images in green and infrared channels separately to roughly identify the snow covered pixels 3. Identifying different cover types on the basis of supervised and unsupervised classification 4. Distinguishing snow covered and transition zones through RGB combination of infrared, red and green channel respectively Figure 3: Geographical location of study area

3 Result & Discussion Yazghil Glacier The Yazghil Glacier is located in Gilgit Agency, Karakoram. The main stream originating from this glacier is Shimshal River,, flows into the Hunza River which in turn is a tributary of the Indus River, located geographically at 36º 15`N to 36º 24`N and 75º 17`E to 75º 23`E and ALOS AVNIR image of Oct 2007 were made which indicates slight decrease in the glacial area of 1.2 sq km during 1992 and 2007 (Fig 4, Table 1). Yazghil Glacier is facing north where the sun rays are falling oblique on its surface. Figure 5: Shows temporal variation in Snow covered area of Jutmau Glacier ( ). White color shows snow and ice covered area and brown color shows snow free area. Jutmau Glacier is facing south hence receives more sun light which may be the cause of more loss of snow cover area. Figure 4: Shows temporal variation in Snow covered area of Yazghil Glacier ( ). White color shows snow and ice covered area and brown color shows snow free area. Passu Glacier The Passu glacier is located in the south of Batura glacier, located geographically 36º 27 N to 36º 28 N and 74º 38 E to 74º 52 E. It feeds River Hunza in northern Pakistan which flows west to east. Jutmau Glacier The Jutmau Glacier is located in the north of Hisper Glacier in Gilgit Agency, located geographically at N to N and E to E and ALOS AVNIR image of Oct 2007 were made which indicates that Jutmau Glacier has lost glacial area of 6 sq km area during 1992 and 2007 (Fig 5, Table 1). Figure 6: Shows temporal variation in Snow covered area of Passu Glacier ( ). White color shows snow and ice covered area and brown color shows snow free area.

4 2001 and ALOS AVNIR image of Sept 2008 were made which indicates that Passu Glacier has lost glacial area of 3.2 sq km area during 1992 and 2008 (Fig 6, Table 1). 199 Batura Glacier, Gilgit Agency 200 Ghulkin Glacier The Ghulkin glacier is located in the south of Batura Glacier, located geographically 36º 24 N to 36º 25 N and 74º 43 E to 74º 52 E. It feeds River Hunza in northern Pakistan which flows west to east. Figure 8: Shows temporal variation in Snow covered area of Batura Glacier ( ) Biafo Glacier- Baltistan, Pakistan Figure 9: Shows temporal variation in Snow covered area of Biafo Glacier ( ) Figure 7: Shows temporal variation in Snow covered area of Ghulkin Glacier ( ). White color shows snow and ice covered area and brown color shows snow free area and ALOS AVNIR image of Sept 2008 were made which indicates that Ghulkin Glacier has lost glacial area of 3.2 sq km area during 1992 and 2008 (Fig 7, Table 1). Previously study of two glaciers named Batura and Biafo was made and presented in The First Joint PI Symposium of ALOS Data Nodes for ALOS Science Program in Kyoto. It was observed from the temporal analysis of Landsat TM and ETM+ data that 17 sq km snow cover area of Batura Glacier and 8.5 sq km area of Biafo Glacier have depleted (Table 1). Temporal analyses of six glaciers situated in Gilgit Agency of Pakistan have been made under the three years ALOS research program (Fig. 10). Fig. 12 represents percent loss in glaciated area experienced by the six glaciers during study period. Batura Biafo Yazghil Jutmau Passu Ghulkin Figure 10: Location of glaciers in study area

5 Figure 11: SRTM DEM of study area Table 1: Depleted area of the glaciers during Name of Glacier Depleted Area (km 2 ) (% loss) Study Period Batura 17 (15 %) Biafo 8.5 (9 %) Yazghil 1.2 (5 %) Jutmau 6 (28 %) Passu 3.2 (7 %) Ghulkin 0.5 (12 %) % Loss in Glaciated Area during Study Period 7% 12% 28% 15% 5% 9% Batura Biafo Yazghil Jutmau Passu Ghulkin Figure 12: Graph shows percent loss in glaciated area during study period Conclusion 1. 20th century was a period of dramatic glacier retreat 2. In the last 25 years +0.3 C warming caused temperatures rise 3. Receding and wasting glaciers are signs of global climate change 4. Due to glacier-melt there could be less amount of melt-water to sustain our agriculture and industrial activities 5. The study shows that glaciated areas of the respective glaciers have decreased near their bases 6. It is noticeable that Jutmau Glacier faces south and receives more sun light suffered more losses than Yazghil Glacier where sun rays fall oblique on its surface Reference 7. A Study of Glaciers in Northern Pakistan, Rahmatullah Jilani, proceeding of first joint ALOS PI symposia from Nov The Effect of Glacier Melt water on an Agro-Pastoral-Society in Himalaya Nepal 9. Yongping SHEN, An Overview of Glaciers, Retreating Glaciers and Their Impact in the Tibetan Plateau 1996 Wake and Mayewski NASA s Goddard Institute for Space Studies, Global Temperature Rise Accelerating, Report by Earth Policy Institute, USA 11. Dorothy K. Hall, Algorithm Theoretical Basis Document (ATBD) for the MODIS Snow and Sea Ice-Mapping Algorithm 12. Impact of climate change on fresh water resources of Pakistan IUCN Climate Change Seminar, Muzaffarabad AJK, 18 March Risk-reduction-project-in-the- Himalayas.html report of the Working Group of Himalayan Glaciology (WGHG) of the International Commission for Snow and Ice (ICSI)