hydrology of mountainous areas in the upper indus basin ... indus...hydrology of mountainous areas...

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

Zulfiqar Ahmad & Mohsin Hafeez &

Iftikhar Ahmad

Received: 10 October 2010 /Accepted: 29 August 2011 /Published online: 23 November 2011# Springer Science+Business Media B.V. 2011

Abstract Mountainous areas in the northern Pakistanare blessed by numerous rivers that have greatpotential in water resources and hydropowerproduction. Many of these rivers are unexploitedfor their water resource potential. If the potentialof these rivers are explored, hydropower produc-tion and water supplies in these areas may beimproved. The Indus is the main river originatingfrom mountainous area of the Himalayas ofBaltistan, Pakistan in which most of the smallerstreams drain. In this paper, the hydrology of themountainous areas in northern Pakistan is studiedto estimate flow pattern, long-term trend in riverflows, characteristics of the watersheds, and vari-ability in flow and water resource due to impact of

climate change. Eight watersheds including Gilgit,Hunza, Shigar, Shyok, Astore, Jhelum, Swat, andChitral, Pakistan have been studied from 1960 to2005 to monitor hydrological changes in relationto variability in precipitation, temperature andmean monthly flows, trend of snow melt runoff,analysis of daily hydrographs, water yield and runoffrelationship, and flow duration curves. Precipitationfrom ten meteorological stations in mountainous areaof northern Pakistan showed variability in the winterand summer rains and did not indicate a uniformdistribution of rains. Review of mean monthlytemperature of ten stations suggested that the UpperIndus Basin can be categorized into three hydrolog-ical regimes, i.e., high-altitude catchments with largeglacierized parts, middle-altitude catchments south ofKarakoram, and foothill catchments. Analysis ofdaily runoff data (1960–2005) of eight watershedsindicated nearly a uniform pattern with much of therunoff in summer (June–August). Impact of climatechange on long-term recorded annual runoff of eightwatersheds showed fair water flows at the Hunza andJhelum Rivers while rest of the rivers indicatedincreased trends in runoff volumes. The study of thewater yield availability indicated a minimum trend inShyok River at Yogo and a maximum trend in SwatRiver at Kalam. Long-term recorded data used toestimate flow duration curves have shown a uniformtrend and are important for hydropower generation forPakistan which is seriously facing power crisis in last5 years.

Environ Monit Assess (2012) 184:5255–5274DOI 10.1007/s10661-011-2337-7

Z. Ahmad (*)Department of Earth Sciences,Quaid-i-Azam University Islamabad,Islamabad 45320, Pakistane-mail: [email protected]

M. HafeezInternational Centre of water for food security (IC Water),Charles Sturt University,Wagga Wagga, NSW, Australiae-mail: [email protected]

I. AhmadCollege of Earth and Environmental Sciences,Punjab University,Lahore, Pakistane-mail: [email protected]

Keywords Eight watersheds . Climate change .

Himalayan Regions . Hunza . Shyok . Astore . Recentfloods . 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 andcarry appreciable glaciers melt water that is ultimatelyused for the sustainable development of the country. Themain river in which most of the smaller streams drain isthe longest Indus River originating from mountainousareas of Himalayas of Baltistan, Pakistan. The IndusRiver provides a major source of water for agricultureand hydropower in Pakistan. Hydrology ofmountainousareas in Northern Pakistan is studied to estimate flowpattern, long-term trend in river flows, and othercharacteristics of the watersheds.

Location of study area

The Indus River originates from the Karakoram,Hindukush, and Himalayan regions in north and flowstoward south with an annual average volume of 178billion m3 which is to be discharged into the IndusPlains while remaining flow drains into the ArabianSea. A major part of the runoff for the sustainabledevelopment of food production in Pakistan is contrib-uted from northern area. Location of study area isshown in Fig. 1.

Research Objectives

The main objective of the study includes investigationof hydrology of the mountainous areas of northernPakistan over the period of 1960–2005. The watershedshave been identified to investigate the characteristics ofthese mountains (Fig. 2), hydrometeorological studies

Fig. 1 Location map of study area

5256 Environ Monit Assess (2012) 184:5255–5274

including estimation of precipitation and temperatureover the area, and hydrological studies comprisingestimation of mean monthly flows, trends of long-termannual flows, flow durations and water yield of thewatersheds. Flood studies include estimation of peakdischarges and their frequencies in various mountainousrivers of northern Pakistan. Sediment transport studiesare composed of estimation of sediment yields and theirrelationships with discharge and area of watersheds.

Data collection

Mountainous rivers in northern area of Pakistan havegreat potential for hydropower generation. Therefore,these rivers have been gauged by Water and PowerDevelopment Authority (WAPDA) since 1960. Mete-orological data were being observed by the PakistanMetrological Department since 1955. Data collectionwas carried out from these agencies for the presentstudy. Procurement of data from these agencies hasbeen a difficult task because most of the reliable datafor the region is available commercially. Satellite datawere downloaded from public domain websites freeof charge (e.g., http://glcf.umiacs.umd.edu and http://glovis.usgs.gov). Available data in published materialprovided important source for this study (PARC 2005and PARC et al. 2005). Climate data were obtainedfor ten stations in the region. Location of hydrologicalstations is shown in Fig. 3. Prior to utilizing data forhydrological analysis, quality of data was checkedapplying statistical tests. These tests include consis-tency, double mass curve and test for outliers. Most ofthe data was found consistent and free of outliers.

These results indicated that data is reliable and maybe used for further analysis.

Literature review

Hydrological aspects of the Himalayan region werestudied by Alford (1992) and Ali (1989). Theagriculture use of melt water was investigated byButz (1989), while Butz and Hewitt (1986) describedinventory of weather stations in Upper Indus Basin.Effect of avalanche snow transport on runoff wasstudied by de Scally and Gardner (1988) and deScally (1992). Ferguson et al. (1984) investigated theuseful techniques for estimating snow melt waterrunoff. Hewitt (1985, 1986, and Hewitt 1988)presented extensive work on Upper Indus Basinincluding snow and ice hydrology and sources ofwater yield. Hewitt and Young (1993) worked fortraining in water resources development in UpperIndus Basin. Hydrological investigations were carriedout at Biafo Glacier Indus River by Hewitt et al.(1989). Hydrological features of the Batura Glacierwere studied by Li and Cai (1981). Makhdoom andSolomon (1986) and Kirch (1987) described runoffforecasting methods in Upper Indus Basin. Evolutionof lakes in the Karakoram was described in detail (Liet al. 1991). Snow and Ice Hydrology Project ofWAPDA (1987) provided detail information on theIndus Basin. The core source of hydrological andmeteorological data is available in the form of publica-tions of WAPDA (1961–2005a, vol. I, 1961–2005b,vol. II, 1961–2005c, vol. III), WAPDA (2003) thatinclude river discharge data, precipitation, temperature,relative humidity, wind speed, and sediment transport.Details of runoff hydrology in cold regions were wellexplained by Hewitt and Young (1990). A character-ization of streams temperature in Pakistan was inves-tigated by Steele (1982). Yang (1981) and Yang andHu (1992) worked on the study of glacier snowmeltresources and characterization of runoff in glaciatedareas of China. A comprehensive work on climate andhydrology in mountainous areas was carried out by deJong et al. (2005), which included snow and ice melt,soil water and permafrost, evapotranspiration and waterbalance, interaction of meteorology and hydrology, andclimate change impact on mountain hydrology (Youngand Hewitt 1990; Singh and Kumar 1997). Seasonalinflow forecasting with a hydrological model wasFig. 2 Selected watersheds in present study

Environ Monit Assess (2012) 184:5255–5274 5257

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http://glovis.usgs.gov

investigated by Druce (2001). Khan (1995) studied theeffect of snow avalanches on hydrology of the KunharRiver in Pakistan. A rainfall and snowmelt runoffmodeling approach was carried out for estimating flowin ungauged sites (Micovic and Quick 1999). Quick(1995) developed watershed model of University ofBritish Columbia for its application to snowmelt areas.Inventory of glaciers and glacial lakes and theidentification of Potential Glacial Lake Outburst

Floods in the Mountains of the Himalayan Regionwere studied by PARC (2005).

The watershed areas

Eight watersheds have been selected to determine thehydrology of mountainous area of northern Pakistan.These watersheds include Gilgit, Hunza, Shigar, Shyok,

Fig. 3 Location of hydrological stations

River Gauge Catchment

Basin Location Latitude Longitude Elevation (masl) Area (km2)

Gilgit Gilgit 35°–55′–35″ 74°–18′–25″ 1,430 12,095

Hunza Dainyor 35°–55″–40′ 74°–22″–35′ 1,350 13,157

Shigar Shigar 35°–20″–00′ 75°–25″–00′ 2,438 6,610

Shyok Yogo 35°–11″–00′ 76°–06″–00′ 2,469 33,670

Astore Doyian 35°–32″–42′ 74°–42″–15′ 1,583 4,040

Jhelum Azad Pattan 33°–43″–47′ 73°–36″–10′ 485 26,485

Swat Kalam 35°–28″–10′ 72°–35″–40′ 1,921 2,020

Chitral Chitral 35°–51″–48′ 71°–47″–15′ 1,500 11,396

Table 1 List of selectedwatersheds


Astore, Jhelum, Swat, and Chitral as shown in Fig. 2.Some physical features of these watersheds weregathered from the available topographic data andpresented in Table 1.

Precipitation

Precipitation is not uniform over the upper Indus Basin.Annual precipitation ranges between 100 mm in theGilgit area to a maximum of 1,500 mm on the mountainslopes at Murree. Snowfall at higher altitudes accountsfor most of the river runoff. An isohyetal map of meanannual precipitation (1954–2004) was constructed andshown in Fig. 4, which indicated that lowest precipi-tation occurs at Gilgit and highest at Murree. Similarlymean monthly distribution of precipitation (1954–2004) of ten stations in mountainous area of theNorthern Pakistan is shown in Fig. 5, which indicatedthat at certain stations (e.g., at Skardu) winter rainfall ishigher while at other station summer rainfall is higher(e.g., at Muzaffarabad). The monthly distribution ofrainfall in the northern area shows a great variabilityand does not exhibit a uniform pattern. The averagemonthly temporal distribution of precipitation revealsthe highest in the months of March to April (e.g., atChitral station) while the lowest in the months ofJanuary and December at most of the stations.

Temperature

In contrast to non uniform pattern of precipitation inthe region, mean temperature shows comparativelyuniform patterns. In the present study, the distributionof mean monthly temperature of the ten selectedstations for the period 1954–2004 is shown in Fig. 6.Analysis of the climatic influence on hydrologicalregimes in the northern Areas is investigated byArcher (2003, 2004) who suggested that the UpperIndus Basin can be divided into three hydrologicalregimes. First one refers to high-altitude catchmentswith large glacierized parts (e.g., Hunza and Shyokwatersheds) with summer runoff that is stronglydependent on concurrent energy input represented bytemperature. Second one refers to middle-altitudecatchments south of the Karakoram (e.g., AstoreWatershed) that have summer flow mostly dependenton preceding winter precipitation while the third one isthe foothill catchments (Khan 1995) that have a runoffregime controlled mainly by current liquid precipitation,predominantly in winter but also during the monsoon.Fowler and Archer (2005) indicated that in Upper IndusBasin during period of 1961–1999, there were signif-icant increases in winter, summer and annual precipi-tation and significant warming occurred in winter whilstsummer showed a cooling trend. The impact of these

Fig. 4 Isohyetal map of mean annual precipitation (1954–2004)


climate changes will directly bear upon water resourceavailability.

Runoff

Recorded daily runoff data (1960–2005) for eightwatersheds have been processed to determine themonthly distribution of flows in the region. At certainlocations the data collected was of shorter duration asthe gauging stations were installed in later period(Fig. 7). In contrast to precipitation, these graphsshowed nearly a uniform pattern indicating much ofthe runoff in summer (June–August) except Jhelum atAzad Pattan which showed to be early riser. Theeffect of climate change has been investigated pickingup simple trend lines on long-term recorded annualrunoff in the selected eight watersheds (Fig. 8).

Except Hunza and Jhelum rivers, rest of the riversshowed increased trends in runoff volumes. Archer(2003) mentioned that summer runoff on the high-altitude glacier-fed catchments is positively correlatedwith summer temperatures. He suggested a 17%increase in summer runoff for Shyok for 1°C tempera-ture rise. However, runoff and temperature are nega-tively correlated onmiddle-altitude snow-fed catchments.He demonstrated that in such a variety of runoffresponses to changes in the climatic variables means thatit would be complicated to predict runoff response toclimate change.

Variation in daily discharges

Daily recorded data of selected stations wereanalyzed to determine any significant variations in

Jan

Feb

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Apr

May

Jun

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GilgitGupis

BunjiSkardu

ChitralAstor

NaltarKalam

MuzaffarabadMurree

-10

10

30

Tem

pera

tute

(Deg

ree

C)

Fig. 6 Mean monthlytemperatures (1954–2004)

Jan

Feb

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Gilgit

Gupis

Bunji

Skardu

Chitral

Astor

Naltar

Kalam

Muzaffarabad

Murree

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100

Pre

cipi

tatio

n(m

m)

Fig. 5 Mean monthlyprecipitations (1954–2004)


Fig. 7 Variability of mean monthly discharge in eight watersheds of Northern Pakistan


Trend of Flows in Hunza River at Dainyor Annual Flows (1966-2004)

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Trend of Flows in Shigar River at Shigar Annual Flows (1985-2001)

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(m

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Annual Flows (1966-2004)

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Trend of Flows Shyok River at Yogo Annual Flows (1973-2004)

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Trend of Flows in Swat River at Kalam Annual Flows (1961-2005)

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Trend of Flows in Chitral River at Chitral Annual Flows (1964-2006)

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Trend of Flows in Astore river at Doiyan Annual Flows (1974-2005)

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Trend of Flows in Jhelum River at Azad Pattan Annual Flows (1978-2005)

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Fig. 8 Trend of runoff in eight watersheds of Northern Pakistan


flows. Hydrographs shown in Fig. 9 exhibit consis-tent trend in daily values, however, except in Jhelumat Azad Patten where an extreme flood of about10,000 m3/s was recorded in September 1992 at thislocation.

Water yield, runoff relationships, and rise and fallin watersheds

One of the important factors for better availability of waterin a region refers to water yields of its watershed. Water

Fig. 9 Yearly hydrographs for selected periods in watersheds of Northern Pakistan


yield map and bar graph were therefore constructed toinvestigate this parameter (Fig. 10a, b). On comparativebasis, water yield is found to be maximum in Swat River(>1.3 million m3 (mcm)/km2) at Kalam while it is mini-mum in Shyok River at Yogo. The water yields in rest ofthe watersheds are comparable and uniform. Relationshipbetween water yield and watershed area has shown adecreasing trend in water yield with the increase inwatershed area on the semi log plot (Fig. 11). Annualvolume of runoff relationship shows a good correlation(R2=0.95) in Fig. 12 and may be used for estimatingrunoff in the region where it is not recorded. Rise andfall of monthly discharges are quite similar in these water-sheds except Jhelum at Azad Pattan where high peak isshown in the months of May, June, and July (Fig. 13).Whereas specific monthly runoff shows uniform rise andfall in these rivers including Jhelum at Azad Pattan

(Fig. 14). The long-term recorded daily data (1968–2005) was used to estimate flow duration curves in these

Water Yield in WatershedsNorthern Pakistan

y = 4.9284x-0.1858

R2 = 0.5087

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unof

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q km

)

WatershedsHunzaGilgitShigarSwatChitralAstoreJhelum

Fig. 11 Water yield relationship (semi log plot)

Water yield in watersheds

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Fig. 10 a Water yield map.b Water yield bar graph inNorthern Pakistan


selected watersheds (Fig. 15), which has indicated auniform trend in these curves. These curves play an im-portant role for hydropower development of the region.

Inferences from floods

Frequencies of long-term recorded instantaneous floods(1960–2005) were estimated and presented in Fig. 16.

The floods in the Indus River result from intensemonsoon rainfall supplemented by melt flood includingoutburst 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 largelandslide dams. Therefore, the Indus basin above BashaDam is protected from penetration of monsoon rains bythe western extremity of the Himalayan mountain range.

Statistical flood estimation

The records of annual maximum daily instantaneousfloods in Gilgit at Gilgit and Hunza at Kalam for theperiod 1960 to 2005 were analyzed using variousfrequency distributions that include Gumbel, Log-Pearson, Lognormal, observed frequency and Pearson(Fig. 17). Skewness is one of the important factorswhile fitting various theoretical frequency distribu-tions. Because the plots in Fig. 17 show greatvariation in the tails of the curves, therefore a mapof coefficient of skewness is prepared and shown inFig. 18 with its three dimension view in Fig. 19. Mapshowing specific maximum discharge (in m3/s/km2) is

Jan

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Gilgit at Gilgit

Hunza at Dainyor

Shigar at Shigar

Shyok at Yogo

Chitra at Chitrall

Swat at Kalam

Astore at Doyian

Jhelum at azadPattan

Fig. 13 Comparison of mean monthly discharges

Runoff RelationshipWatersheds in Northern Pakistan

y = 4.9284x0.8142

R2 = 0.9521

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Fig. 12 Runoff relationship (linear plot)


also constructed to identify the variation in thequantum of floods in the region. Specific maximumdischarge tends to decrease in north of the region asshown in Fig. 20 with its three dimension view inFig. 21.

Satellite image

A wide range of remote sensing data is available inpublished material (PARC 2005). The mosaic ofLandsat-7 images covering the glaciated region ofPakistan shown in Fig. 22 is obtained from previouslypublished material (PARC et al. 2005).

Glaciers

In the upper Indus Basin of northern Pakistan 5,218glaciers with their total area coverage of about15,040 km2 were identified and mapped by Campbell(2005) (Fig. 23). Occurrences of glaciers in eachRiver Basin are variable but the areal coverage by theHunza River Basin (4,677 km2) is the largest amongothers.

Climate change and water shortages

Akhtar et al. (2008) presents estimates of water resourceschanges in three river basins in the Hindukush–Karakorum–Himalaya region associated with climatechange. Generally, temperature and precipitation wouldshow an increase towards the end of the twenty-firstcentury, and their results indicated higher risk of floodproblems due to climate change.

The findings of the present study have also indicatedincrease in runoff in rivers of the Upper Indus Basin,Northern Pakistan, which may be attributed to apreliminary evidence of the climate change in Pakistan.

Approximately 70% of the freshwater are frozen inglaciers in Pakistan, which buffer ecosystems againstclimate variability by releasing water during dry seasonsor years. In tropical areas, glaciers contributing to streamflow often provide the only source of water for humansand wildlife during dry parts of the year. Freshwater isalready a limiting resource in Pakistan and in the next25 years population growth is likely to far exceed thanany potential increases in available water.

Aquifers of the Lower Indus Basin (federal capital ofIslamabad and Rawalpindi cities) are rapidly depleting

Jan

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ShyokChitral

HunzaGilgit

JhelumAstor

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Gilgit at Gilgit

Hunza at Dainyor

Shigar at Shigar

Shyok at Yogo

Chitra at Chitrall

Swat at Kalam

Astore at Doyian

Jhelum at azadPattan

Fig. 14 Comparison of specific monthly runoff in the watersheds


Hunza River at DainyorFlow Duration (1975-2004)

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Gilgit River at GilgitFlow Duration (1968-2005)

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Swat River at KalamFlow Duration (1976-2005)

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Shyok River at YogoFlow Duration (1976-2005)

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Shigar River at ShigarFlow Duration (1985-2005)

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Chitral River at ChitralFlow Duration (1976-2005)

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Astore River at DoiyanFlow Duration (1976-2005)

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Jhelum River at Azad PattanFlow Duration (1976-2005)

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Fig. 15 Flow duration of eight watersheds in Northern Pakistan. Percent time represents time percentage a discharge remains in a year


2000.001800.001600.001400.001200.001000.00800.00600.00

Shigar

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2000.001750.001500.001250.001000.00750.00

Chitral

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3500.003000.002500.002000.001500.001000.00500.00

Gilgit

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6000.005000.004000.003000.002000.001000.00

Dainyor

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4000.003500.003000.002500.002000.001500.001000.00

Yogo

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Fig. 16 Frequency of instantaneous floods in the watersheds. All floods values along x-axes are given in m3/s


due to excessive pumping round the clock without havingappreciable annual recharge from rainfall. As a resultannual water balance of hydrological budget has neverbeen equalized and therefore a drastically decline in waterlevels is beingmonitored for more than one decade. On anaverage basis about 60% of the country’s water require-ment is met by the melt water of glaciers and remainingby the annual amount of rainfall (shortfall of 30% in rainsobserved in 2009) (Ahmad and Ahmad 2008). Most ofour large cities are dependent on melt water fromglaciers for their water supply and hydroelectric power,

and communities are already experiencing shortages andconflicts over use. (Ashraf and Ahmad 2008).

Impact of climate on flooding

Rapid melting of glaciers can lead to flooding ofrivers 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 lakescan cause catastrophic glacial lake outburst floods.

Fig. 18 Map showing coefficient of skewness of flood peaks

Flood Frequencies Gilgit River at Gilgit (1960-2006)

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5000

6000

7000

0.1 1 10 100 1000 10000Period of Return (Years)

Pea

k D

isch

arge

(m

3 /se

c)

Gumbel

LogPearson

Lognormal

Observed Frequency

Pearson

Flood Frequencies Hunza River at Dainyor (1966-2003)

0

2000

4000

6000

8000

10000

12000

0.1 1 10 100 1000 10000

Period of Return (Years)

Gumbel

LogPearson

lognormal

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3 /se

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Fig. 17 Flood frequency curves based on Gumbal, Log-Pearson, Lognormal, observed frequency and Pearson


Recent rainfall in Pakistan in the months of July–August, 2010, which delivered unprecedented cumu-lative rainfall of 9,988 mm in Pakistan, has set aunique example leading to the impact of climatechange. Floods killed several people and destroyedbridges, houses, and arable land. Fertile lands in thecities of Sawat and Nowhera have completedundulated with the deposition of layers of trans-ported debris as much as that owners are unable to

even recognize their lands. About 20.5 millionpeople have been affected by flooding acrossPakistan as per estimates of the European Commis-sion’s Aid and Civil Protection Unit (ECHO). Whilethe floods in Pakistan cannot be attributed entirely toclimate change, the intensity of this disaster isconsistent with predictions that global warming willincrease the severity and frequency of extremeweather events.

Fig. 20 Map showing specific maximum discharge (m3/s/km2)

-0.200.20.40.60.811.21.41.61.822.22.42.62.833.23.4

Coefficient of Skew

Fig. 19 Three dimensionview of coefficient ofskewness of flood peaks


The devastating floods in Pakistan highlight thestark reality of the world’s changing climatic patternsand the impact of this will have on vulnerablepopulations. Most recent rainfall data of 15 July2010 to 25 August 2010 is shown in Table 2. Risingsea level is one of the most widely discussed andpotentially significant problems associated with glob-al warming. Not only does a large proportion of theglobal population live in areas likely to be affected bysea-level rise, but the long adjustment time of the

world’s oceans means that, in principle, the processwill be difficult to reverse (Khan et al. 2002).

Sea-level changes at the shoreline due to tidal motiontake place over a period of hours; those changes that aredue to movements of continental plates take place overmillennia. Between these two extremes, the timescale onwhich rises in sea-level attributed to climate change arelikely to occur will be decades to centuries.

In August 2010, tidal rise in sea level at the shoresof Arabian Sea, Karachi which posed a bigger threat

Fig. 21 Three-dimensionalview of specific maximumdischarge (m3/s/km2)

Fig. 22 Mosaic of Landsat-7 ETM+ images of thenorthern glaciated regionof Pakistan (PARCet al. 2005)


of not accommodating the flood water of the IndusRiver at the outfall region into the sea.

Conclusions

The conclusions drawn from this study are based onlong-term recorded hydrometeorological, hydrologi-cal, and flood data procured from various agenciesthat are given.

1. Comparison of rain data from ten meteorologicalstations in mountainous area of northern Pakistanhas indicated extreme variability in the winter andsummer rains and a uniform distribution of rainshave not been observed. The average monthlytemporal distribution of precipitation reveals a

highest peak in the months of March and April (atChitral station) and lowest rain in the months ofJanuary and December at most of the other stations.

2. As compared with the no uniform pattern ofprecipitation in the region, mean temperatureshows almost a uniform pattern. Review of meanmonthly temperature of ten stations (1954–2004)suggests that the Upper Indus Basin can be dividedinto three hydrological regimes as given below:

(a) High-altitude catchments with large glacierizedparts (e.g., Hunza and Shyok) with its summerrunoff strongly dependent on concurrent energyinput by temperature.

(b) Middle-altitude catchments south of Karakoram(e.g., Astore) that regulates summer flowmostlydependent on preceding winter precipitation.

(c) Foothill catchments that regulates flowsmainlycontrolled by current liquid precipitation pre-dominantly in winter as well as in monsoon.

3. Since 1961 to 1999, significant increases in winter,summer and annual precipitation, and significantwarming occurred in winter while summer showeda cooling trend may be referred to phenomena ofclimate change will have its impact on waterresource availability.

4. Recent floods in Pakistan in one way or anotherappear to be related to the impact of climatechange. During July–August 2010, a cumulativerainfall of 9,988 mm fell over Pakistan is quite

Fig. 23 Glaciers of the Upper Indus Basin

Table 2 Cumulative Rainfall (15 July 2010 to 25 August2010)

Country and provinces Rainfall (mm)

Pakistan 9,988

Punjab 5,897

Sindh 1,038

Baluchistan 166

Khyber Pakhtunkhwa (formerly knownas North Western Frontier Province)

1,621

Gilgit Baltistan 565


unique and has caused humongous damages tostructures and mankinds.

5. Analysis of daily runoff data (1960–2005) for theeight selected watersheds indicated nearly a uni-form pattern with much of the runoff in summer(June–August) except Jhelum at Azad Pattan thathas shown an early rise in the runoff commencingfrom April.

6. Impact of climate change has been studied byvisual examination of trend lines on long-termrecorded annual runoff (1960–2005) of eightwatersheds. Except the Hunza and Jhelum Riv-ers, rest of the rivers showed increased trends inrunoff volumes. However, runoff and tempera-ture are negatively correlated on middle-altitudesnow-fed catchments. As a matter of fact, due tovariety of runoff responses to changes in theclimatic variables it is complicated to predictrunoff to climatic change.

7. The study of the water yield availability indicated aminimum trend in Shyok River at Yogo and amaximum trend in Swat River at Kalam. The wateryields in rest of the watersheds are comparable anduniform.

8. Long-term recorded data (1960–2005) used toestimate flow duration curves for the eightwatersheds has shown a uniform trend and areimportant for hydropower generation of Pakistan.

Acknowledgments The authors gratefully acknowledge Aus-training International and the Department of Education,Employment and Workplace Relations (DEEWR) for providingpost-selection support services and funding the research underthe executive Endeavour Award 2010. We also acknowledgeLauren Fyfe—case manager of Austraining—and Sue Kendallof the International Centre of water for food security (ICWater), Charles Sturt University, Wagga Wagga, for timelysupport and provision of the essentials of research. Water andDevelopment Authority, Pakistan Meteorology Development,Department of Earth Sciences, Quaid-i-Azam University, andCollege of Earth and Environmental Sciences, Punjab Universityare highly acknowledged for providing access to reliable data towork on and to publish valuable information.

References

Ahmad, Z., & Ahmad, I. (2008). Groundwater modeling studyof the Potowar area, Rawalpindi using Visual Modflowmodel, Rawalpindi environmental improvement project(REIP) of Water and Sanitation Agency (WASA), unpub-lished report (by Asian Development Bank)

Akhtar, M., Ahmad, N., & Booij, M. J. (2008). The impact ofclimate change on the water resources of Hindukush–Karakorum–Himalaya region under different glacier coveragescenarios. Journal of Hydrology, 355(1–4), 148–163.

Alford, D. (1992). Hydrological Aspects of the HimalayanRegion. ICIMOD Occasional Paper, no. 18. Kathmandu.

Ali, G. (1989). Some Hydrological Aspects of snowmelt runoffunder summer conditions in the Barpu Glacier Basin,Central Karakoram, Himalaya, Northern Pakistan. Unpub-lished M.A. thesis. Waterloo: Wilfrid Laurier University.

Archer, D. R. (2003). Contrasting hydrological regimes in theupper Indus Basin. Journal of Hydrology, 274(198–2), 10.

Archer, D. R. (2004). Hydrological implications of spatial andaltitudinal variation in temperature in the Upper IndusBasin. Nordic Hydrology, 35(3), 213–227.

Ashraf, A., & Ahmad, Z. (2008). Regional groundwaterflowmodeling of upper Chaj Doab, Indus Basin. GeophysicalJournal International (GJI), 173, 17–24. doi:10.1111/j.1365-246X.2007.03708.x.

Butz, D. A. O. (1989). The agricultural use of meltwater inHopar settlement, Pakistan. Annals of Glaciology, 13, 35–39.

Butz, D. A. O., & Hewitt, K. (1986). A note in the Upper IndusBasin Weather Stations. In K. Hewitt (Ed.), Snow and icehydrology project: annual report (pp. 64–76). Waterloo:Wilfrid Laurier University.

Campbell, J. G. (2005) Inventory of Glaciers, Glacial Lakesand the Identification of Potential Glacial Lake OutburstFloods (GLOFs) Affected by Global Warming in theMountains of India, Pakistan and China/Tibet. Interna-tional Centre for Integrated Mountain Development, G. P.O. Box 3226, Kathmandu

De Jong, C, Collins, D., & Ranzi, R. (2005) (Eds) Climate andhydrology in mountain areas. Wiley, Chichester.

de Scally, F. A. (1992). Influence of avalanche snow transport onsnowmelt runoff. Journal of Hydrology, 137(1–4), 73–97.

de Scally, F. A., & Gardner, J. S. (1988) The hydrologicalimportance of avalanche snow, Kaghan Valley, Himalayanmountains, Pakistan. In Proceedings of the InternationalSnow Science Workshop, pp. 277–283. Vancouver: CanadianAvalanche Association

Druce, D. J. (2001). Insights from a history of seasonal inflowforecasting with a conceptual hydrologic model. Journalof Hydrology, 249, 102–112.

Ferguson, R. I., Collins, D. N., & Whalley, W. B. (1984).Techniques for investigating meltwater runoff and erosion.In K. J. Miller (Ed.), The International Karakoram Project(pp. 374–382). Great Britain: Cambridge University Press.

Fowler, H. J., & Archer, D. R. (2005). Hydro-climatologicalvariability in the Upper Indus Basin and implications forwater resources. In Regional Hydrological Impacts ofClimatic Change—Impact Assessment and Decision Making(Proceedings of symposium S6 held during the SeventhIAHS Scientific Assembly at Foz do Iguaçu, Brazil,April 2005). IAHS Publ. 295

Hewitt, K. (1985) Snow and ice hydrology in remote, highmountain basins: the Himalayan sources of the RiverIndus. In Snow and Ice Hydrology Project Working PaperNo. 1. Waterloo: Wilfrid Laurier University

Hewitt, K. (1986). The Upper Indus snow belts: SNOWFALLand sources of water yield. In K. Hewitt (Ed.), Snow and


http://dx.doi.org/10.1111/j.1365-246X.2007.03708.x

http://dx.doi.org/10.1111/j.1365-246X.2007.03708.x

ice hydrology project: annual report 1985 (pp. 58–63).Waterloo: Wilfrid Laurier University.

Hewitt, K. (1988). The snow and ice hydrology project:research and training for water resource development inthe Upper Indus basin. Journal of Canada—PakistanCooperation, 2(1), 63–72.

Hewitt, K., Young, G. J. (1990) Snow and ice hydrology project:handbook of snow and ice hydrology IV: runoff hydrology.Waterloo: Cold Regions Research Centre, Wilfrid LaurierUniversity

Hewitt, K., Young, G. J. (1993). The Snow and Ice HydrologyProject: a Pakistan-Canada research and training programme.In: Young, G. J. (ed.), Snow and Glacier Hydrology.International Symposium, Kathmandu, Nepal, 16–21November 1992. Proceedings. International Associationof Hydrological Sciences. IAHS/AISH Publication, no.218: 49–58.

Hewitt, K., Wake, C., Young, G. J., & David, C. (1989).Hydrological investigations at Biafo Glacier, KarakoramHimalaya, Pakistan: an important source of water for theIndus River. Annals of Glaciology, 13, 103–108.

Khan, M. I. (1995) The effects of snow avalanches on thehydrologic regime of the Kunhar river, Western Himalayan,Pakistan: analysis and application to river flow forecasting.M.A.Sc. Thesis, Department of Civil Engineering, Universityof British Columbia, Vancouver, p. 148.

Khan, T. M. A., Razzaq, D. A., Chaudhry, Q., Quadir, D. A.,Kabir, A., & Sarker, M. A. (2002). Sea level variations andgeomorphological changes in the coastal belt of Pakistan.Marine Geodesy, 25(1), 159–174. 1521-060X.

Kirch, J. (1987) Upper Indus Basin, Snow and Ice RunoffForecasting Project. Project Identification Mission Report,714/0014720 to C.I.D.A

Li, N., & Cai, X. (1981). Discussion on some hydrologicalfeatures of the Batura Glacier, Karakoram. Journal ofGlaciology and Cryopedology, 3(2), 7–12.

Li, B., Zharng, Q., & Wang, F. (1991). Evolution of lakes in theKarakoram-west Kunlun mountains. Quaternary Sciences,1, 64–71.

Makhdoom, M. T. A., & Solomon, S. I. (1986). Attemptingflow forecasts of the Indus River, Pakistan using remotelysensed snow cover data. Nordic Hydrology, 17, 171–184.

Micovic, Z., & Quick, M. C. (1999). A rainfall and snowmeltrunoff modeling approach to flow estimation at ungaugedsites in British Columbia. Journal of Hydrology, 226, 101–120.

Pakistan Water and Power Development Authority (WAPDA)(1987) Snow and Ice Hydrology Project Annual Report 1985,1986, 1987. Lahore: Hydrology and Research Directorate.

Pakistan Water and Power Development Authority (WAPDA).Hydrology and System Analysis Organization (1961–2005)

Annual Report of River and Climatological Data ofPakistan: Vol. I: River Discharge, Sediment and QualityData. Lahore: Surface Water Hydrology Project.

Pakistan Water and Power Development Authority (WAPDA).Hydrology and System Analysis Organization (1961–2005)Annual Report of River and Climatological Data ofPakistan: Vol. II: Daily and Hourly Precipitation Data.Lahore: Surface Water Hydrology Project.

Pakistan Water and Power Development Authority (WAPDA).Hydrology and System Analysis Organization. (1961–2005) Annual Report of River and Climatological Dataof Pakistan: Vol. III: Precipitation, Evaporation, Temper-atures, Relative Humidity, Solar Radiation and WindMovement Data. Lahore: Surface Water HydrologyProject.

Pakistan Water and Power Development Authority (WAPDA).Hydrology and System Analysis Organization. (2003).Sediment appraisal of Pakistan rivers 1960–1990. Lahore:Surface Water Hydrology Project.

PARC (2005). Inventory of Glaciers and Glacial Lakes and theIdentification of Potential Glacial Lake Outburst Floods(GLOFs) Affected by Global Warming in the Mountainsof Himalayan Region, Pakistan Agricultural ResearchCouncil Islamabad.

PARC, APN, UNEP, START, and ICIMOD (2005) Inventory ofGlaciers and Glacial Lakes and the Identification of PotentialGlacial Lake Outburst Floods (glofs) Affected by GlobalWarming in the Mountains of Himalayan Region

Quick, M. C. (1995). U.B.C. Watershed Model Manual-Version4. Vancouver: Department of Civil Engineering Universityof British Columbia.

Singh, P., & Kumar, N. (1997). Impact assessment of climatechange on the hydrological response of a snow and glaciermelt runoff dominated Himalayan river. Journal ofHydrology, 193, 316–350.

Steele, T. D. (1982). A characterization of streams temperaturesin Pakistan using harmonic analysis. Hydrological SciencesJournal, 27(4), 451–467.

Yang, Z. (1981). Basic characteristics of runoff in contemporaryglaciated areas of China. Scientia Sinica, 24(10), 1418–1430.

Yang, Z, & Hu, X. (1992). Study of glacier meltwater resourcesin China. In Hooke RL (ed.), Symposium on MountainGlaciology, Lanzhou, Gansu Province, China, 26–30August 1991. Proceedings. Annals of Glaciology, vol. 16.pp. 141–145.)

Young GJ, Hewitt K (1990) Hydrology research in the upperIndus basin, Karakoram Himalaya, Pakistan. InternationalAssociation Hydrological Sciences. International Associa-tion of Hydrological Sciences. IAHS Publication No. 190,139–152


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