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Monitoring and Mapping Batura Glacier using Remote Sensing 1Sarah Hasan, 2Hafiz Usman Ahmed Khan, 3Shahid Iqbal, 4Muhammad Humza, 5Mubashir Hassan, 6Shahid Parvez UNOOSA pu.edu.gov.pk United Nations/Pakistan International Workshop on Integrated Use of Space Technologies for Food and Water Security. Islamabad, 11-15 March 2013 ABSTRACT 3. STUDY AREA Pakistan being a glacier resource rich country always requires proper monitoring, mapping and estimation for better planning and decision making particularly. All these very important areas of natural resources & environmental monitoring & mapping can easily be addressed with the advanced technologies of remote sensing and GIS techniques. The present work on Monitoring and Mapping of Batura Glacier was carried out by using Remote Sensing and GIS techniques. Batura has significant role among the glaciers found in Himalaya region of Pakistan. The purpose of this study is to analyze changes in the area of Batura during melting of ice, extent of Batura during different seasons and area analysis. The area estimation of Batura Glacier was conducted by applying various image processing techniques; including but not limited to image rectification & enhancements, image clipping, unsupervised classification using ISODATA and K-means clustering, and NDSI etc have been utilized on temporal images of LANDSAT acquired from July 1998 to August 2011 of the study area. The Remote Sensing and GIS techniques are found to be very useful in quantifying the snow covered area in Batura Glacier based on Landsat Images. Key Words: 4. METHODS AND PROCESS INPUT Dataset Batura Glacier is one of the largest glaciers outside the polar region. It is 57 km long is one of the eight largest glaciers in the middle and low latitude. It lies in the north of Passu 7,500 meter above sea level, located geographically at 36o 30`N to 36o 40`N and 74o 22` 33``E to 74o 52` 30``E. In northern Pakistan it feeds River Hunza that flows west to east below the north side of the peaks of Batura Muztagh (7,795 m) from the maximum elevation 6,200 m into the upper Hunza valley at 2,516 m. The total drainage area about 690 km2, with about ice covered area is 320 km, although the directly contiguous glaciers of the Batura proper have an area of 285 km2. The glacier consists of five main ice flows and over 20 smaller tributary glaciers. NDSI Landsat Multi-date Imageries Normalized Difference Snow Index Classification Unsupervised Pre-processing Rectification Band Stripping Outputs Image Enhancements Snow Covered Area AOI Subsets Spatial Temporal Change a 1-SATELLITE IMAGE b Remote Sensing, Snow Index, GIS, Landsat, Batura Glacier 7-NDSI c 1.INTRODUCTION Pakistan has a high number of Glaciers that covers an area of some 13,680 sq km which serve as a natural regulator of regional water supplies and are enormous reservoirs of fresh water. The water melt from these glaciers serve as an important resource which feed rivers in Pakistan. By ice flux, ablation and velocity Chinese investigation group concluded that Batura glacier should stop advancing during the period 1997-1999, with a predicted further advance of 180-240 m before that time, taking to within 300 m of the Highway. Starting from the 1990's they predict that the glacier will once again decline and this will last for at least 20 to 30 years. Batura glacier does not have a similar temporal fashion it remained virtually stationary from 1885 to the 1940's and then retreat which occurred in the 1950's and 1960's and the subsequent advance (both real and predicted) perhaps shows a pattern which is related to advanced to larger scale changes in the regional environment. Chinese glaciologists (BGIG, 1979) found evidence that the Batura Glacier was not a surging glacier, but predicted that its terminus would advance in the 1980s to threaten the KKH and then retreat in the 1990s. Our study aims at the analysis of snow covers area and extend of Batura glacier in different season situated in the Northern area of Pakistan. (a) Pakistan with the general study area specified in red color. (b) Study area and adjoining region. (c) Study area – Batura Glacier 5-CLIPPING 5.RESULTS Land cover varies season to season due to temperature differences as shown in the graphs of different years. In the images of July month we have observed the less snow as compared to other seasons due to melting. In 2010 there were very less snow due to high temperature in that year and causes destruction in Hunza valley because Hunza River is the main catchment of BATURA GLACIER. In each year there were gradual changes in glacier melting. The graph shows that Glacier is melting year by year and causing a disturbance in ecosystem. Main catchment of Hunza River is Indus basin which shows the increased level of water in mainly in month of July, which fulfills our water requirement as our country Pakistan is agriculture country and mainly depends upon on melted water and the water is also used for electricity production. 45 40 Sq.miles 35 30 25 20 15 10 5 BATURA GLACIER NORTHERN AREA MAP 0 BATURA GLACIER MAPPING IN 1974 1998 July 2002 July 2009 July 2011 July years 2. DATA Snow covered area Imagery: Landsat Temporal data from 07/28/1998 to 10/12/2011 GIS data: Shape file of Batura Glacier Snow free area The graph shows the trend of Batura Glacier. The graph shows the temporal changes of snow covered area in the month of July in Batura Glacier. It is clear from the images that in 1998, 2002, 2009 and 2011 there is continuous decrease in snow covered area. Landsat TM Landsat ETM+ Operated by NASA NASA Launched 1982 1999 Orbit Sun-synchronous Sun-synchronous Altitude 705 Km 705 Km Temporal resoloution 16 days 16 days Spatial resoloution 30*30 m 30*30 m Temporal Changes of snow in Batura Glacier The water from the Indus River and its tributaries supports the vastness of the agricultural water supply for its 130 million people. Dams on the main branch of the Indus River and its tributaries produce about 45% of the electrical energy for Pakistan. And the main contribution of power generation is from Batura Glacier. Due to melting of Glacier in the summer season the huge amount of water is available in the month of July but the electricity demands is not achieved through this water because we have no more dams on that glacial lakes to produce more electricity. Snow covered area Snow free area 70 60 50 40 30 20 10 0 BATURA GLACIER SATELLITE IMAGE BATURA GLACIER SHAPEFILE Legends Snow covered area in the image Snow free area in classified image Rocks and snow free area in the image Snow covered area in classified image 6. CONCLUSIONS • Based on the processing and analysis of Landsat images acquired from 1998 to 2011 (downloaded from USGS Earth Explorer), it was found that overall there is a fluctuation trend in snow cover of the Batura Glacier. However, this trend was observed decreasingly while analyzing the data for the month of July each year. • Unsupervised classification and NDSI of Landsat images are highly use full for accurate snow cover classification and area estimation. Moreover, Landsat temporal images are highly useful for snow cover monitoring and mapping. • Remote sensing and GIS technologies are highly helpful in identification, mapping, estimation and exploitation of glaciers spread over spatial domain. Moreover, monitoring temporal as well as environmental variations in these glaciers could also be addressed using these technologies.. Snow free area in NDSI image Snow in NDSI image 7. RECOMMENDATIONS • The snow cover trend can better be understood by expanding the time series analysis depending on the availability of historical datasets. • There is a need to conduct comprehensive study about Batura Glacier using Microwave and Hyper-spectral imageries to sort out discrepancies found in optical imageries due to weather and shadowing effects as well as signature limitations of multispectral imageries. • Availability of ground based data e.g water melting, discharge, velocity, snow falling, snow depth, etc would also be helpful for comparison of results in such studies. REFERENCES • Ahmed, A., Iftikhar, H., & Chaudhry, G. M. Water Resources and conservation Strategy of Pakistan. • Allan, N. J. R. (1995). Karakorum Himalaya-A SORCEBOOK FOR A PROTECTED AREA. Karachi: The World Conservation Union, Pakistan. • A study of Glaciers in Northern Pakistan. Karachi: Pakistan Space & Upper Atmosphere Research Commission (SUPARCO). • Jilani, R., Haq, M., & Naseer, A. Monitoring of Mountain Glacial Variations in Northern Pakistan, from 1992 to 2008 using Landsat and ALOS Data. Karachi: Pakistan Space & Upper Atmosphere Research Commission (SUPARCO). • Raina, V.K.(2009). Himalayan Glaciers – Behaviour and Climate Change.