Climatic changes on hydrological cycles in Pakistan
Climate is the statistics of weather over long periods of time. It is different from the weather in the sense that it is measured through variations in a given region over long periods of time.
Human history is filled with such climatic changes mainly owing to the small changes in the Earth Orbit that leads to alteration in received solar radiations by the earth’s atmosphere. On the other hand, the devastating effects of global warming we are witnessing now have their roots in human activities. Since the dawn of the industrial revolution in the 20th century, numbers of industries established and the magnitude of traffic on roads have skyrocketed without putting any checks and balances in place to evaluate and contain their harmful effects on our climate.
According to a definition, Global warming is termed as the general increase in the average temperature of the earth affecting ecological systems across the globe, and besides having several direct impacts on human species, it also threatens the very existence of fauna and flora that guarantees human survival possible in the first place. Scientists have observed an increase of 1.62 degrees Fahrenheit (0.9 degrees Celsius) in Earth’s surface temperature due to the surge in the emissions of carbon dioxide and other greenhouse gases like Methane CH4, Nitrous Oxide N2O, and Water vapors H20) with most of the increase occurred in the last 35 years while 2016 was recorded as the warmest years. Due to the incredible and unmatched ability of water to take in the heat, there has been a 0.4 degrees Fahrenheit increase in the temperature of oceans since 1969. Scientists have predicted a rise of 1.5 1.5° and 5.3°C (34.7° to 41.5°F) in average temperature by 2100 if the CO2 emissions keep on rising at current momentum.
According to European Environment Agency,
The hydrological cycle is the continuous circulation of water within the Earth’s hydrosphere and is driven by solar radiation. This includes the atmosphere, land, surface water, and groundwater.
It entails the continuous water movement from across various small and large water reservoirs and storehouses, like rivers, seas, oceans, and the atmosphere and ground, and includes the processes like precipitation, condensation, surface runoff, subsurface flow, infiltration, and evaporation, and also from different physical forms of water. Climate change has been expediating the water cycles, leading to soared amounts of evaporated water to the atmosphere as hotter airs can store far more water bringing extreme weather events like floods and typhoons in some areas while some others face intense drought and water shortages. These asymmetrical changes also contribute to the erosion of the upper beneficial layer of lands dried up by temperature rise.
In the last century, global sea levels have risen up to 8 inches but this rate went double in the last two decades and its pace isn’t changing.
Industrialization caused a 30 percent increase in the acidity of ocean surfaces owing to the increased carbon absorptions due to inflated carbon emissions by humans. Oceans have been taking in almost 2 billion tons of CO2 per year. Besides being an environmental and societal catastrophe, climate change is also at the roots of shocking economic damages due to its effects on the hydrological cycles. It’s also a major concern for Pakistan with altered patterns of river flows, melting glaciers, more Glacier Lake Outburst Floods (GLOFs), and other intense climatic events accompanied by the reduced water storage capacities of our water reservoirs caused by siltation and sedimentation, which is leading deteriorating water quality, dropping areas of wetlands and an impending water crisis at our hands. Floods are one of the major natural calamities in Pakistan. These are mainly caused by heavy concentrated rainfall over the upper catchments of the main rivers. Pakistan has a unique flood-related problem in the sense that the greater part of the flood generating upper catchments of the rivers. All of this demand gathering date from different but particular sites in the upper riparian country India, for which an excellent platform has already been provided, Commissioners of Indus water treaty but severe deep-rooted political conflicts between both countries have diminished any hopes for a constructive dialogue, even in the face of climate change.
Pakistan’s canal irrigation system or formally known as Indus River System was originally developed under British rule a hundred years ago and is recognized as World’s largest irrigation system gets 65% of its freshwater massive glaciers located in the Karakorum-Hindukush-Himalaya (KHH) ranges. Mismanagement and incompetent water policies have added to the impacts of climate change which has made water shortages a prime issue for the present and future governments. It has also endangered the livelihoods of our 60 % population residing in the rural areas which directly and indirectly is linked with Agriculture.
Few recommendations from our side have been enlisted to counter the effects of the water crisis due to climate change knocking at our doors.
The first and foremost priority of the Government of Pakistan should be the acknowledgment of the water crisis as a serious threat to our future generations, that recognition can pave the way for further dialogue and accompanied decisive actions.
Recently, Prime Minister Shahid Khaqan Abbasi announced Pakistan’s First ever National Water Policy which is a positive development in the way of facing this challenge.
The fragmented and multi-layered regulatory structure of the Pakistan government in the water sector calls for streamlining the bureaucracy as it has been hindering the development of water policies due to different points of view on various issues regarding the water crisis held by different departments.
A crucial and much-needed requirement to cope with the effects of climate change is countrywide Reforestation campaigns as put in place by Prime Minister Imran Khan.
Raising awareness in the population regarding the judicious application of water in day-to-day tasks.
Putting an end to the unrestricted flow of industrial waste into the freshwater reservoirs and that needs to be addressed at the highest possible levels in Federal and Provincial governments.
Reducing the annual water losses of Pakistan which currently stands at 48maf which demands the adoption of Sprinkler and Drip Irrigation Systems facilitated by government and private sector cooperation.
An increase in water prices and their efficient collection should also be considered to improve the infrastructure of water reservoirs and distribution channels.
Immediate need to built new small and large dams on an emergency basis before it gets too late to recover the damage done at the hand of climate change
Deepened coordination between the various governmental institutions like ministries of water and agriculture which initiate and carry out the water projects.
Authors: Dr Harron Zaman, Muhammad Atif Shabir, Muhammad Bilal Farooq, Anas Afzal, Asif Iqbal ,Nadeem Akbar