The Indus River, originating in the western part of Tibet, passes through Jammu and Kashmir, from the Kunlun mountain range to the main Great Himalayas to the south, flowing through Ladakh, Gilgit-Baltistan, and KPK, and then flows along the Punjab and Sindh ultimately outfall into the Arabian Sea.
The Indus River is vital for Pakistan and the foundation of the green economy including environmental safeguard, agriculture, food security and hydropower generation.
Economic development, massive degradation of riverine forest and mangroves in the Indus delta, and cultivation of crops are also affect water resources management, Indus river runoff patterns and sedimentation transport, which will change the hydrographs, impacts river morphology, water storage, and other practices.
The glaciers are vital lifelines because 70 to 80 pre cent share of the Indus water is from Himalayan glaciers whose situation is extremely complex due to climate change.
If they melt, water availability will be in jeopardy.
Due to rising of temperature, glaciers will melt rapidly.
This will cause outbursts and bring flash floods in the catchment areas of Indus River.
The consequences of receding glaciers and variation in the timing, duration and intensity of the monsoon precipitation are caused by extreme events.
Riverine forests are significant in reducing the impacts of climate change on Indus river ecology, habitat and can support natural flow regimes particularly prevent to sea water intrusion since the Indus delta has already lost about 75 per cent of its original forest cover due to reduced environmental flows and further upstream diversion would be devastating for Indus Delta.
Salinity on the Sindh coast increased from 35ppt to 45ppt in two decades.
5 Million hectares of fertile land in Thatta district alone (or 12 per cent of the entire cultivated area of the province) is affected by sea intrusion.
Changes in the amount of rainfall, with regard of monsoon seasons in 2010, 2011 have been witnessed.
Recently the amount of snowfall during the winter season in 2012 and 2013 to 2014 and heavy rainfall in India as well as upper/northern areas of Pakistan provide evidence that the water cycle has already changed.
According to Intergovernmental Panel on Climate Change (IPCC) reports, by 2050 the annual run-off is projected to decline by 27 per cent.
Certainly all the impacts of climate change would affect the quantity and quality of Indus water.
These include rising Arabian sea levels causing salinisation of agricultural land and ground water; sinking natural ground levels (land subsidence) along the coastal area by more than 2.
5 inches per decade, the rapid melting of the Himalaya glaciers which initially increase but subsequently decrease the water resource; disruption of the monsoon precipitation patterns which would either cause droughts or flooding; and other extreme events such as earthquakes, storms, tsunamis and violent cyclones which would threaten human settlements and water infrastructure, sea intrusion and submergence of islands including the groundwater aquifers.
Torrential rains and cloud bursts have increased in intensity due to changing weather pattern will create much more frequent and flash flooding as well as drought in the catchment area of Indus river basin.
Predicting future climate conditions have indirectly been signified in the planning and designing, operation and safeguarding of water resource systems.
The Indus River has come under persistent stress due to cumulative climate change; about more than 85 per cent waters used by the agriculture sector, economic development, construction of dams subsequent obstructing environmental flows towards downstream riparian, industrial waste, saline groundwater and agricultural effluents, untreated waste and sewage as well as mismanagement of water.
The less interest has been paid from the policy makers to the climate changes that were occurred in hydrological cycle over the past two decades.
That issue should be taken on a priority basis for implementing.
It is pertinent to mention here that the at some stage, in design and evaluation, hydraulic infrastructures should use the exceptionally high (super-flood) levels.
There is also a need to raise and strengthen dykes along Indus river and include climate change adjustment in design and evaluation in order to improve performance during extreme events.
It is essential to pay much more attention in incorporating climate change considerations and impacts into in operation and management systems as we can face a great challenge of climate change.
National and provincial disaster management and concerned authorities should implement national climate change policy at grass roots level to mitigate the impacts of varying climate patterns and unpredictable monsoon rains.
Climate adaptation plans should be developed for the water, agriculture and irrigation sectors in order to prevent the growing threat of floods in Indus River include efficient watershed management and the restoration of riverine forests, mangroves and associated biodiversity.
There is a dire need for strengthening early warning systems, installation of glacier monitoring stations, modern Doppler weather radars, and automatic weather stations to forecast extreme weather events like torrential rains, floods, earthquakes, glacial lake outburst, droughts and monitor weather phenomena, including storms and tsunamis in advance.
Source: The Nation
Byline: Imran Aziz
December 27, 2016