Firdos Khan Yousafzai, PhD student, University of Klagenfurt, Austria, and YSSP 2012 participant
In Pakistan, water supply fell from 5,260 cubic meters per capita in 1951 to 1,050 cubic meters per capita in 2010 according to the World Bank, and is likely to further fall in the future. According to the Falkenmark Water Stress Indicator, a country or a part of a country is said to experience “water stress” when the annual water supplies drop below 1,700 cubic meters per capita per year, and “water scarcity” if the annual water supplies drop below 1,000 cubic meters per capita per year. Water scarcity is especially critical for Pakistan because agriculture contributes 25% of the GDP and 36% of energy is obtained from hydropower.
In terms of geography, Pakistan is incredibly diverse, ranging from plain to desert, hills, forest, and plateaus from the Arabian Sea in the south and to the mountains of Karakorum in the north of the country. It has 796,096 square kilometers area—about the same size as Turkey–and approximately 200 million inhabitants.
Water availability is also different in different parts of the country. While various studies showed that climate change is happening all over Pakistan, research shows that the northern areas are more vulnerable. Possible reasons include the increasing population and deforestation, among others. Therefore, in my PhD work, which was also the subject of my work in the 2012 IIASA Young Scientists Summer Program, I am investigating that how fast climate is changing and exploring its impacts on availability of water.
In a recent study we investigated this issue under four different climate change scenarios, from 2006 to 2039 in the future. Different scenarios have different assumptions about population growth, use of energy type, environmental protection, economic development, technological changes, etc. We calculated the changes on the basis of baseline and future time periods for climate and hydrological projections. We found an increasing trend in maximum and minimum temperature, while precipitation is also changing under each scenario.
To assess water availability and investigate the impacts of changing climate on the operation of reservoirs, we used Tarbela Reservoir as a measurement tool, developing hydrological projections for the reservoir under each scenario. Tarbela Dam is one of the biggest dams in the world, and has a storage capacity of approximately 7 million acre feet and the potential to produce 3,400 megawatts of electricity.
In our study, we considered all the relevant parameters related to water shortages and surpluses. To compare the status of water availability, we compared the baseline period and future time period. The results show an increasing trend in water availability, however, water scarcity is observed during some months under each scenario. Further, we also observed that there is a 23-40% increase in river flow under the considered scenarios while the average increase is approximately 35% during the future time period.
As a conclusion we can say that enough water is available in Pakistan, and will continue to be available in the future. Instead, the study confirms previous reports that the major problem is mismanagement.
The possible solution may include constructing more dams and storage capacity to store extra water during high river flow which then can be utilized during low river flow. This could probably also be helpful in flood control, raise the groundwater level, and provide cheap and clean electricity to national electricity grid—providing multiple benefits, in view of the fact that the country has faced ongoing energy crises for many years.
Ali S, Li D, Congbin F, Khan F (2015). Twenty first century climatic and hydrological changes over Upper Indus Basin of Himalayan region of Pakistan. Environmental Research Letters10 (2015) 014007. DOI:10.1088/1748-9326/10/1/014007.
Khan F, Pilz J, Ali S (2017). Improved hydrological projections and reservoir management in the Upper Indus Basin under the changing climate. Water and Environmental Journal. Vol. 31, No. 2, pp. 235-244. DOI:10.1111/wej.12237.
Khan F, Pilz J, Amjad M, Wiberg D (2015). Climate variability and its impacts on water resources in the Upper Indus Basin under IPCC climate change scenarios. International Journal of Global Warming, Vol. 8, No. 1, pp. 46-69. DOI:10.1504/IJGW.2015.071583.
This article gives the views of the author, and not the position of the Nexus blog, nor of the International Institute for Applied Systems Analysis.