Hydrology of mountainous areas in the upper Indus Basin, Northern Pakistan with the perspective of climate change

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1 Environ Monit Assess (212) 184: DOI 1.17/s Hydrology of mountainous areas in the upper Indus Basin, Northern Pakistan with the perspective of climate change Zulfiqar Ahmad & Mohsin Hafeez & Iftikhar Ahmad Received: 1 October 21 / Accepted: 29 August 211 / Published online: 23 November 211 # Springer Science+Business Media B.V. 211 Abstract Mountainous areas in the northern Pakistan are blessed by numerous rivers that have great potential in water resources and hydropower production. Many of these rivers are unexploited for their water resource potential. If the potential of these rivers are explored, hydropower production and water supplies in these areas may be improved. The Indus is the main river originating from mountainous area of the Himalayas of Baltistan, Pakistan in which most of the smaller streams drain. In this paper, the hydrology of the mountainous areas in northern Pakistan is studied to estimate flow pattern, long-term trend in river flows, characteristics of the watersheds, and variability in flow and water resource due to impact of Z. Ahmad (*) Department of Earth Sciences, Quaid-i-Azam University Islamabad, Islamabad 4532, Pakistan fz97@hotmail.com M. Hafeez International Centre of water for food security (IC Water), Charles Sturt University, Wagga Wagga, NSW, Australia mhafeez@csu.edu.au I. Ahmad College of Earth and Environmental Sciences, Punjab University, Lahore, Pakistan hydromod@yahoo.com climate change. Eight watersheds including Gilgit, Hunza, Shigar, Shyok, Astore, Jhelum, Swat, and Chitral, Pakistan have been studied from 196 to 25 to monitor hydrological changes in relation to variability in precipitation, temperature and mean monthly flows, trend of snow melt runoff, analysis of daily hydrographs, water yield and runoff relationship, and flow duration curves. Precipitation from ten meteorological stations in mountainous area of northern Pakistan showed variability in the winter and summer rains and did not indicate a uniform distribution of rains. Review of mean monthly temperature of ten stations suggested that the Upper Indus Basin can be categorized into three hydrological regimes, i.e., high-altitude catchments with large glacierized parts, middle-altitude catchments south of Karakoram, and foothill catchments. Analysis of daily runoff data (196 25) of eight watersheds indicated nearly a uniform pattern with much of the runoff in summer (June August). Impact of climate change on long-term recorded annual runoff of eight watersheds showed fair water flows at the Hunza and Jhelum Rivers while rest of the rivers indicated increased trends in runoff volumes. The study of the water yield availability indicated a minimum trend in Shyok River at Yogo and a maximum trend in Swat River at Kalam. Long-term recorded data used to estimate flow duration curves have shown a uniform trend and are important for hydropower generation for Pakistan which is seriously facing power crisis in last 5 years.

2 5256 Environ Monit Assess (212) 184: Keywords Eight watersheds. Climate change. Himalayan Regions. Hunza. Shyok. Astore. Recent floods. The Indus River Introduction Northern Pakistan is comprised of mountainous areas, which are covered by snow, glacial lakes, and glaciers. Numerous streams originate from these mountains and carry appreciable glaciers melt water that is ultimately used for the sustainable development of the country. The main river in which most of the smaller streams drain is the longest Indus River originating from mountainous areas of Himalayas of Baltistan, Pakistan. The Indus River provides a major source of water for agriculture and hydropower in Pakistan. Hydrology of mountainous areas in Northern Pakistan is studied to estimate flow pattern, long-term trend in river flows, and other characteristics of the watersheds. Location of study area The Indus River originates from the Karakoram, Hindukush, and Himalayan regions in north and flows toward south with an annual average volume of 178 billion m 3 which is to be discharged into the Indus Plains while remaining flow drains into the Arabian Sea. A major part of the runoff for the sustainable development of food production in Pakistan is contributed from northern area. Location of study area is shown in Fig. 1. Research Objectives The main objective of the study includes investigation of hydrology of the mountainous areas of northern Pakistan over the period of The watersheds have been identified to investigate the characteristics of these mountains (Fig. 2), hydrometeorological studies Fig. 1 Location map of study area

3 Environ Monit Assess (212) 184: including estimation of precipitation and temperature over the area, and hydrological studies comprising estimation of mean monthly flows, trends of long-term annual flows, flow durations and water yield of the watersheds. Flood studies include estimation of peak discharges and their frequencies in various mountainous rivers of northern Pakistan. Sediment transport studies are composed of estimation of sediment yields and their relationships with discharge and area of watersheds. Data collection Mountainous rivers in northern area of Pakistan have great potential for hydropower generation. Therefore, these rivers have been gauged by Water and Power Development Authority (WAPDA) since 196. Meteorological data were being observed by the Pakistan Metrological Department since Data collection was carried out from these agencies for the present study. Procurement of data from these agencies has been a difficult task because most of the reliable data for the region is available commercially. Satellite data were downloaded from public domain websites free of charge (e.g., and glovis.usgs.gov). Available data in published material provided important source for this study (PARC 25 and PARC et al. 25). Climate data were obtained for ten stations in the region. Location of hydrological stations is shown in Fig. 3. Prior to utilizing data for hydrological analysis, quality of data was checked applying statistical tests. These tests include consistency, double mass curve and test for outliers. Most of the data was found consistent and free of outliers. Fig. 2 Selected watersheds in present study These results indicated that data is reliable and may be used for further analysis. Literature review Hydrological aspects of the Himalayan region were studied by Alford (1992) and Ali (1989). The agriculture use of melt water was investigated by Butz (1989), while Butz and Hewitt (1986) described inventory of weather stations in Upper Indus Basin. Effect of avalanche snow transport on runoff was studied by de Scally and Gardner (1988) and de Scally (1992). Ferguson et al. (1984) investigated the useful techniques for estimating snow melt water runoff. Hewitt (1985, 1986, and Hewitt 1988) presented extensive work on Upper Indus Basin including snow and ice hydrology and sources of water yield. Hewitt and Young (1993) worked for training in water resources development in Upper Indus Basin. Hydrological investigations were carried out at Biafo Glacier Indus River by Hewitt et al. (1989). Hydrological features of the Batura Glacier were studied by Li and Cai (1981). Makhdoom and Solomon (1986) and Kirch (1987) described runoff forecasting methods in Upper Indus Basin. Evolution of lakes in the Karakoram was described in detail (Li et al. 1991). Snow and Ice Hydrology Project of WAPDA (1987) provided detail information on the Indus Basin. The core source of hydrological and meteorological data is available in the form of publications of WAPDA ( a, vol. I, b, vol. II, c, vol. III), WAPDA (23) that include river discharge data, precipitation, temperature, relative humidity, wind speed, and sediment transport. Details of runoff hydrology in cold regions were well explained by Hewitt and Young (199). A characterization of streams temperature in Pakistan was investigated by Steele (1982). Yang (1981) and Yang and Hu (1992) worked on the study of glacier snowmelt resources and characterization of runoff in glaciated areas of China. A comprehensive work on climate and hydrology in mountainous areas was carried out by de Jong et al. (25), which included snow and ice melt, soil water and permafrost, evapotranspiration and water balance, interaction of meteorology and hydrology, and climate change impact on mountain hydrology (Young and Hewitt 199; Singh and Kumar 1997). Seasonal inflow forecasting with a hydrological model was

4 5258 Environ Monit Assess (212) 184: Fig. 3 Location of hydrological stations investigated by Druce (21). Khan (1995) studied the effect of snow avalanches on hydrology of the Kunhar River in Pakistan. A rainfall and snowmelt runoff modeling approach was carried out for estimating flow in ungauged sites (Micovic and Quick 1999). Quick (1995) developed watershed model of University of British Columbia for its application to snowmelt areas. Inventory of glaciers and glacial lakes and the identification of Potential Glacial Lake Outburst Floods in the Mountains of the Himalayan Region were studied by PARC (25). The watershed areas Eight watersheds have been selected to determine the hydrology of mountainous area of northern Pakistan. These watersheds include Gilgit, Hunza, Shigar, Shyok, Table 1 List of selected watersheds River Gauge Catchment Basin Location Latitude Longitude Elevation (masl) Area (km 2 ) Gilgit Gilgit ,43 12,95 Hunza Dainyor ,35 13,157 Shigar Shigar ,438 6,61 Shyok Yogo ,469 33,67 Astore Doyian ,583 4,4 Jhelum Azad Pattan ,485 Swat Kalam ,921 2,2 Chitral Chitral ,5 11,396

5 Environ Monit Assess (212) 184: Astore, Jhelum, Swat, and Chitral as shown in Fig. 2. Some physical features of these watersheds were gathered from the available topographic data and presented in Table 1. Precipitation Precipitation is not uniform over the upper Indus Basin. Annual precipitation ranges between 1 mm in the Gilgit area to a maximum of 1,5 mm on the mountain slopes at Murree. Snowfall at higher altitudes accounts for most of the river runoff. An isohyetal map of mean annual precipitation ( ) was constructed and shown in Fig. 4, which indicated that lowest precipitation occurs at Gilgit and highest at Murree. Similarly mean monthly distribution of precipitation ( ) of ten stations in mountainous area of the Northern Pakistan is shown in Fig. 5, which indicated that at certain stations (e.g., at Skardu) winter rainfall is higher while at other station summer rainfall is higher (e.g., at Muzaffarabad). The monthly distribution of rainfall in the northern area shows a great variability and does not exhibit a uniform pattern. The average monthly temporal distribution of precipitation reveals the highest in the months of March to April (e.g., at Chitral station) while the lowest in the months of January and December at most of the stations. Temperature In contrast to non uniform pattern of precipitation in the region, mean temperature shows comparatively uniform patterns. In the present study, the distribution of mean monthly temperature of the ten selected stations for the period is shown in Fig. 6. Analysis of the climatic influence on hydrological regimes in the northern Areas is investigated by Archer (23, 24) who suggested that the Upper Indus Basin can be divided into three hydrological regimes. First one refers to high-altitude catchments with large glacierized parts (e.g., Hunza and Shyok watersheds) with summer runoff that is strongly dependent on concurrent energy input represented by temperature. Second one refers to middle-altitude catchments south of the Karakoram (e.g., Astore Watershed) that have summer flow mostly dependent on preceding winter precipitation while the third one is the foothill catchments (Khan 1995) that have a runoff regime controlled mainly by current liquid precipitation, predominantly in winter but also during the monsoon. Fowler and Archer (25) indicated that in Upper Indus Basin during period of , there were significant increases in winter, summer and annual precipitation and significant warming occurred in winter whilst summer showed a cooling trend. The impact of these Fig. 4 Isohyetal map of mean annual precipitation ( )

6 526 Environ Monit Assess (212) 184: Fig. 5 Mean monthly precipitations ( ) Precipitation (mm) 1 5 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Murree Muzaffarabad Kalam Naltar Astor Chitral Skardu Bunji Gupis Gilgit climate changes will directly bear upon water resource availability. Runoff Recorded daily runoff data (196 25) for eight watersheds have been processed to determine the monthly distribution of flows in the region. At certain locations the data collected was of shorter duration as the gauging stations were installed in later period (Fig. 7). In contrast to precipitation, these graphs showed nearly a uniform pattern indicating much of the runoff in summer (June August) except Jhelum at Azad Pattan which showed to be early riser. The effect of climate change has been investigated picking up simple trend lines on long-term recorded annual runoff in the selected eight watersheds (Fig. 8). Except Hunza and Jhelum rivers, rest of the rivers showed increased trends in runoff volumes. Archer (23) mentioned that summer runoff on the highaltitude glacier-fed catchments is positively correlated with summer temperatures. He suggested a 17% increase in summer runoff for Shyok for 1 C temperature rise. However, runoff and temperature are negatively correlated on middle-altitude snow-fed catchments. He demonstrated that in such a variety of runoff responses to changes in the climatic variables means that it would be complicated to predict runoff response to climate change. Variation in daily discharges Daily recorded data of selected stations were analyzed to determine any significant variations in Fig. 6 Mean monthly temperatures ( ) Temperatute (Degree C) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Murree Muzaffarabad Kalam Naltar Astor Chitral Skardu Bunji Gupis Gilgit

7 Environ Monit Assess (212) 184: Fig. 7 Variability of mean monthly discharge in eight watersheds of Northern Pakistan

8 5262 Environ Monit Assess (212) 184: Trend of Flows in Hunza River at Dainyor Annual Flows ( ) 5 Trend of Flows in Gilgit River at Gilgit Annual Flows ( ) Trend of Flows in Shigar River at Shigar Annual Flows ( ) Discharge (m3/sec) Trend of Flows Shyok River at Yogo Annual Flows ( ) Trend of Flows in Swat River at Kalam Annual Flows ( ) Trend of Flows in Chitral River at Chitral Annual Flows ( ) Trend of Flows in Astore river at Doiyan Annual Flows ( ) 14 Trend of Flows in Jhelum River at Azad Pattan Annual Flows ( ) 2 12 Discharge (m3/sec) Fig. 8 Trend of runoff in eight watersheds of Northern Pakistan

9 Environ Monit Assess (212) 184: Fig. 9 Yearly hydrographs for selected periods in watersheds of Northern Pakistan flows. Hydrographs shown in Fig. 9 exhibit consistent trend in daily values, however, except in Jhelum at Azad Patten where an extreme flood of about 1, m 3 /s was recorded in September 1992 at this location. Water yield, runoff relationships, and rise and fall in watersheds One of the important factors for better availability of water in a region refers to water yields of its watershed. Water

10 5264 Environ Monit Assess (212) 184: Fig. 1 a Water yield map. b Water yield bar graph in Northern Pakistan a Runoff per unit Area (m 3 /km 2 ) b Water yield in watersheds Gilgit Danyr Shigar Yogo Chitral Kalam Doyan Azad Pattan yield map and bar graph were therefore constructed to investigate this parameter (Fig. 1a, b). On comparative basis, water yield is found to be maximum in Swat River (>1.3 million m 3 (mcm)/km 2 ) at Kalam while it is minimum in Shyok River at Yogo. The water yields in rest of the watersheds are comparable and uniform. Relationship between water yield and watershed area has shown a decreasing trend in water yield with the increase in watershedareaonthesemilogplot(fig.11). Annual volume of runoff relationship shows a good correlation (R 2 =.95) in Fig. 12 and may be used for estimating runoff in the region where it is not recorded. Rise and fall of monthly discharges are quite similar in these watersheds except Jhelum at Azad Pattan where high peak is shown in the months of May, June, and July (Fig. 13). Whereas specific monthly runoff shows uniform rise and fall in these rivers including Jhelum at Azad Pattan (Fig. 14). The long-term recorded daily data ( ) was used to estimate flow duration curves in these Annual Runoff (mcm/sq km) Watersheds Hunza Gilgit Shigar Swat Chitral Astore Jhelum Water Yield in Watersheds Northern Pakistan y = x R 2 = Watershed Area (Sq km) Fig. 11 Water yield relationship (semi log plot)

11 Environ Monit Assess (212) 184: Annual Runoff (mcm) Runoff Relationship Watersheds in Northern Pakistan y = x.8142 R 2 =.9521 The floods in the Indus River result from intense monsoon rainfall supplemented by melt flood including outburst floods which result from failure of natural dams. Most of the failures of natural dams are of glacier dams ( Jokulhlaups ). Records also exist of failure of large landslide dams. Therefore, the Indus basin above Basha Dam is protected from penetration of monsoon rains by the western extremity of the Himalayan mountain range Watershed Area (Sq km) Fig. 12 Runoff relationship (linear plot) selected watersheds (Fig. 15), which has indicated a uniform trend in these curves. These curves play an important role for hydropower development of the region. Inferences from floods Frequencies of long-term recorded instantaneous floods (196 25) were estimated and presented in Fig. 16. Statistical flood estimation The records of annual maximum daily instantaneous floods in Gilgit at Gilgit and Hunza at Kalam for the period 196 to 25 were analyzed using various frequency distributions that include Gumbel, Log- Pearson, Lognormal, observed frequency and Pearson (Fig. 17). Skewness is one of the important factors while fitting various theoretical frequency distributions. Because the plots in Fig. 17 show great variation in the tails of the curves, therefore a map of coefficient of skewness is prepared and shown in Fig. 18 with its three dimension view in Fig. 19. Map showing specific maximum discharge (in m 3 /s/km 2 )is Gilgit at Gilgit Hunza at Dainyor Shigar at Shigar Shyok at Yogo Chitra at Chitrall Swat at Kalam Astore at Doyian Jhelum at azad Pattan 2 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Disharge (m 3 /sec) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jhelum Shyok Hunza Gilgit Chitral Shigar Astor Swat Fig. 13 Comparison of mean monthly discharges

12 5266 Environ Monit Assess (212) 184: Runoff per unit Area (m3/km2) Gilgit at Gilgit Hunza at Dainyor Shigar at Shigar Shyok at Yogo Chitra at Chitrall Swat at Kalam Astore at Doyian Jhelum at azad Pattan Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Runoff per unit area (m 3 /km 2 ) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Swat Shigar Astor Jhelum Gilgit Hunza Chitral Shyok Fig. 14 Comparison of specific monthly runoff in the watersheds also constructed to identify the variation in the quantum of floods in the region. Specific maximum discharge tends to decrease in north of the region as shown in Fig. 2 with its three dimension view in Fig. 21. Satellite image A wide range of remote sensing data is available in published material (PARC 25). The mosaic of Landsat-7 images covering the glaciated region of Pakistan shown in Fig. 22 is obtained from previously published material (PARC et al. 25). Glaciers In the upper Indus Basin of northern Pakistan 5,218 glaciers with their total area coverage of about 15,4 km 2 were identified and mapped by Campbell (25) (Fig. 23). Occurrences of glaciers in each River Basin are variable but the areal coverage by the Hunza River Basin (4,677 km 2 ) is the largest among others. Climate change and water shortages Akhtar et al. (28) presents estimates of water resources changes in three river basins in the Hindukush Karakorum Himalaya region associated with climate change. Generally, temperature and precipitation would show an increase towards the end of the twenty-first century, and their results indicated higher risk of flood problems due to climate change. The findings of the present study have also indicated increase in runoff in rivers of the Upper Indus Basin, Northern Pakistan, which may be attributed to a preliminary evidence of the climate change in Pakistan. Approximately 7% of the freshwater are frozen in glaciers in Pakistan, which buffer ecosystems against climate variability by releasing water during dry seasons or years. In tropical areas, glaciers contributing to stream flow often provide the only source of water for humans and wildlife during dry parts of the year. Freshwater is already a limiting resource in Pakistan and in the next 25 years population growth is likely to far exceed than any potential increases in available water. Aquifers of the Lower Indus Basin (federal capital of Islamabad and Rawalpindi cities) are rapidly depleting

13 Environ Monit Assess (212) 184: Hunza River at Dainyor Flow Duration ( ) Gilgit River at Gilgit Flow Duration ( ) Percent Time Percent Time Shigar River at Shigar Flow Duration ( ) Shyok River at Yogo Flow Duration ( ) Percent Time Percent Time Swat River at Kalam Flow Duration ( ) Chitral River at Chitral Flow Duration ( ) Percent Time Percent Time Astore River at Doiyan Flow Duration ( ) Percent Time Jhelum River at Azad Pattan Flow Duration ( ) Percent Time Fig. 15 Flow duration of eight watersheds in Northern Pakistan. Percent time represents time percentage a discharge remains in a year

14 5268 Environ Monit Assess (212) 184: Frequency 8 6 Frequency Gilgit Dainyor Frequency 2 Frequency Shigar Yogo Frequency 6 Frequency Chitral Kalam Fig. 16 Frequency of instantaneous floods in the watersheds. All floods values along x-axes are given in m 3 /s 6.

15 Environ Monit Assess (212) 184: Flood Frequencies Gilgit River at Gilgit (196-26) Flood Frequencies Hunza River at Dainyor ( ) Peak Gumbel LogPearson Lognormal Observed Frequency Pearson Period of Return (Years) Peak Gumbel LogPearson lognormal Observed Frequency Period of Return (Years) Fig. 17 Flood frequency curves based on Gumbal, Log-Pearson, Lognormal, observed frequency and Pearson due to excessive pumping round the clock without having appreciable annual recharge from rainfall. As a result annual water balance of hydrological budget has never been equalized and therefore a drastically decline in water levels is being monitored for more than one decade. On an average basis about 6% of the country s water requirement is met by the melt water of glaciers and remaining by the annual amount of rainfall (shortfall of 3% in rains observed in 29) (Ahmad and Ahmad 28). Most of our large cities are dependent on melt water from glaciers for their water supply and hydroelectric power, and communities are already experiencing shortages and conflicts over use. (Ashraf and Ahmad 28). Impact of climate on flooding Rapid melting of glaciers can lead to flooding of rivers and to the formation of glacial melt water lakes, which may pose an even more serious threat. Continued melting or calving of ice chunks into lakes can cause catastrophic glacial lake outburst floods. Fig. 18 Map showing coefficient of skewness of flood peaks

16 527 Environ Monit Assess (212) 184: Fig. 19 Three dimension view of coefficient of skewness of flood peaks Coefficient of Skew Recent rainfall in Pakistan in the months of July August, 21, which delivered unprecedented cumulative rainfall of 9,988 mm in Pakistan, has set a unique example leading to the impact of climate change. Floods killed several people and destroyed bridges, houses, and arable land. Fertile lands in the cities of Sawat and Nowhera have completed undulated with the deposition of layers of transported debris as much as that owners are unable to even recognize their lands. About 2.5 million people have been affected by flooding across Pakistan as per estimates of the European Commission s Aid and Civil Protection Unit (ECHO). While the floods in Pakistan cannot be attributed entirely to climate change, the intensity of this disaster is consistent with predictions that global warming will increase the severity and frequency of extreme weather events. Fig. 2 Map showing specific maximum discharge (m 3 /s/km 2 )

17 Environ Monit Assess (212) 184: Fig. 21 Three-dimensional view of specific maximum discharge (m 3 /s/km 2 ) The devastating floods in Pakistan highlight the stark reality of the world s changing climatic patterns and the impact of this will have on vulnerable populations. Most recent rainfall data of 15 July 21 to 25 August 21 is shown in Table 2. Rising sea level is one of the most widely discussed and potentially significant problems associated with global warming. Not only does a large proportion of the global population live in areas likely to be affected by sea-level rise, but the long adjustment time of the world s oceans means that, in principle, the process will be difficult to reverse (Khan et al. 22). Sea-level changes at the shoreline due to tidal motion take place over a period of hours; those changes that are due to movements of continental plates take place over millennia. Between these two extremes, the timescale on which rises in sea-level attributed to climate change are likely to occur will be decades to centuries. In August 21, tidal rise in sea level at the shores of Arabian Sea, Karachi which posed a bigger threat Fig. 22 Mosaic of Landsat- 7 ETM+ images of the northern glaciated region of Pakistan (PARC et al. 25)

18 5272 Environ Monit Assess (212) 184: Fig. 23 Glaciers of the Upper Indus Basin of not accommodating the flood water of the Indus River at the outfall region into the sea. Conclusions The conclusions drawn from this study are based on long-term recorded hydrometeorological, hydrological, and flood data procured from various agencies that are given. 1. Comparison of rain data from ten meteorological stations in mountainous area of northern Pakistan has indicated extreme variability in the winter and summer rains and a uniform distribution of rains have not been observed. The average monthly temporal distribution of precipitation reveals a Table 2 Cumulative Rainfall (15 July 21 to 25 August 21) Country and provinces Rainfall (mm) Pakistan 9,988 Punjab 5,897 Sindh 1,38 Baluchistan 166 Khyber Pakhtunkhwa (formerly known 1,621 as North Western Frontier Province) Gilgit Baltistan 565 highest peak in the months of March and April (at Chitral station) and lowest rain in the months of January and December at most of the other stations. 2. As compared with the no uniform pattern of precipitation in the region, mean temperature shows almost a uniform pattern. Review of mean monthly temperature of ten stations ( ) suggests that the Upper Indus Basin can be divided into three hydrological regimes as given below: (a) (b) (c) High-altitude catchments with large glacierized parts (e.g., Hunza and Shyok) with its summer runoff strongly dependent on concurrent energy input by temperature. Middle-altitude catchments south of Karakoram (e.g., Astore) that regulates summer flow mostly dependent on preceding winter precipitation. Foothill catchments that regulates flows mainly controlled by current liquid precipitation predominantly in winter as well as in monsoon. 3. Since 1961 to 1999, significant increases in winter, summer and annual precipitation, and significant warming occurred in winter while summer showed a cooling trend may be referred to phenomena of climate change will have its impact on water resource availability. 4. Recent floods in Pakistan in one way or another appear to be related to the impact of climate change. During July August 21, a cumulative rainfall of 9,988 mm fell over Pakistan is quite

19 Environ Monit Assess (212) 184: unique and has caused humongous damages to structures and mankinds. 5. Analysis of daily runoff data (196 25) for the eight selected watersheds indicated nearly a uniform pattern with much of the runoff in summer (June August) except Jhelum at Azad Pattan that has shown an early rise in the runoff commencing from April. 6. Impact of climate change has been studied by visual examination of trend lines on long-term recorded annual runoff (196 25) of eight watersheds. Except the Hunza and Jhelum Rivers, rest of the rivers showed increased trends in runoff volumes. However, runoff and temperature are negatively correlated on middle-altitude snow-fed catchments. As a matter of fact, due to variety of runoff responses to changes in the climatic variables it is complicated to predict runoff to climatic change. 7. The study of the water yield availability indicated a minimum trend in Shyok River at Yogo and a maximum trend in Swat River at Kalam. The water yields in rest of the watersheds are comparable and uniform. 8. Long-term recorded data (196 25) used to estimate flow duration curves for the eight watersheds has shown a uniform trend and are important for hydropower generation of Pakistan. Acknowledgments The authors gratefully acknowledge Austraining International and the Department of Education, Employment and Workplace Relations (DEEWR) for providing post-selection support services and funding the research under the executive Endeavour Award 21. We also acknowledge Lauren Fyfe case manager of Austraining and Sue Kendall of the International Centre of water for food security (IC Water), Charles Sturt University, Wagga Wagga, for timely support and provision of the essentials of research. Water and Development Authority, Pakistan Meteorology Development, Department of Earth Sciences, Quaid-i-Azam University, and College of Earth and Environmental Sciences, Punjab University are highly acknowledged for providing access to reliable data to work on and to publish valuable information. References Ahmad, Z., & Ahmad, I. (28). Groundwater modeling study of the Potowar area, Rawalpindi using Visual Modflow model, Rawalpindi environmental improvement project (REIP) of Water and Sanitation Agency (WASA), unpublished report (by Asian Development Bank) Akhtar, M., Ahmad, N., & Booij, M. J. (28). The impact of climate change on the water resources of Hindukush Karakorum Himalaya region under different glacier coverage scenarios. Journal of Hydrology, 355(1 4), Alford, D. (1992). Hydrological Aspects of the Himalayan Region. ICIMOD Occasional Paper, no. 18. Kathmandu. Ali, G. (1989). Some Hydrological Aspects of snowmelt runoff under summer conditions in the Barpu Glacier Basin, Central Karakoram, Himalaya, Northern Pakistan. Unpublished M.A. thesis. Waterloo: Wilfrid Laurier University. Archer, D. R. (23). Contrasting hydrological regimes in the upper Indus Basin. Journal of Hydrology, 274(198 2), 1. Archer, D. R. (24). Hydrological implications of spatial and altitudinal variation in temperature in the Upper Indus Basin. Nordic Hydrology, 35(3), Ashraf, A., & Ahmad, Z. (28). Regional groundwaterflow modeling of upper Chaj Doab, Indus Basin. Geophysical Journal International (GJI), 173, doi:1.1111/ j x x. Butz, D. A. O. (1989). The agricultural use of meltwater in Hopar settlement, Pakistan. Annals of Glaciology, 13, Butz, D. A. O., & Hewitt, K. (1986). A note in the Upper Indus Basin Weather Stations. In K. Hewitt (Ed.), Snow and ice hydrology project: annual report (pp ). Waterloo: Wilfrid Laurier University. Campbell, J. G. 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