Climate Change in Third Pole

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    • The two lakes — Chibzhang Co and Dorsoidong Co — in the Hindu Kush Himalaya region grew larger between October 1987 and 2021. 
      • But much of these glaciers are retreating due to rising temperatures, accelerating ice loss and meltwater runoff.

    Climate Change

    • United Nations-backed research in June 2021 flagged that 
      • Up to 2 billion people in southeast Asia can face food and water shortages 
        • even as the Hindu-Kush-Himalayan (HKH) Region mountain ranges lose up to two-thirds of their ice by 2100.
      • In the future, even if global warming is kept to 1.5 degrees C above the pre-industrialisation levels, 
        • warming in the HKH region is likely to be at least 0.3 degrees C higher, and 
        • In the northwest Himalaya and Karakoram at least 0.7 degrees C higher.

    Third Pole and the Worrying Signs

    • The climate crisis is altering the geography of the Third Pole.
      • The region’s glaciers have been melting faster than any other part of the world.
      • A study published in 2019 on the ice thickness of glaciers estimated that 
        • Glaciers in the HKH may contain 27 per cent less ice than previously suggested.
    • Reasons of retreating, thinning and shrinking of Glaciers 
      • rising temperatures 
      • accelerating ice loss 
      • meltwater runoff.
    • This region also accounts for the largest reserve of freshwater lakes
      • Satellite images from the region have reported growth in the size of its lakes.

    Third Pole

    • Hindu-Kush-Himalayan (HKH) Region is often referred to as the Third pole.
    • It spans over countries like Afghanistan, Bangladesh, Bhutan, China, India, Kyrgyzstan, Mongolia, Myanmar, Nepal, Pakistan, Tajikistan, and Uzbekistan.
    • It traverses about 5 million square kilometres and hosts a large and culturally diverse population.
    • It divides the valley of the Amu Darya (the ancient Oxus) to the north from the Indus River valley to the south.
    • It contains vast cryospheric zones and is also the world’s largest store of snow and ice outside the polar region.

    Observations of  NASA’s Earth Observatory 

    • Two lakes Chibzhang Co and Dorsoidong Co 
      • Location: to the west of the Tanggula Mountains.
        • a small range in the central part of the Tibetan Plateau. 
      • Increase in size 
        • Grew larger between October 1987 (when the first image was acquired) and October 2021 (when the second image was acquired).
        • The area of the lakes grew by 23 per cent between 1976 and 2017, according to the researchers. 
      • Increased Depth
        • The lakes have become much deeper over time.
        • The depth of the channel that connects the two main lobes of the lake increased. 
          • According to data from NASA’s global water monitor, the increase is by about 26 feet between the early 1990s and 2021
      • Water Levels
        • Water levels were much steadier in the lakes that received water from glacial melting than in the lakes that received water from precipitation.
        • About half of the overall increase in the size of lakes was driven by glacial melting.

    Processes that affect the size of the lakes

    • Amount of annual precipitation
    • Rate of evaporation
    • Amount of runoff from melting glaciers
    • Permafrost during summer months.

     

    (Image: October 12, 1987. Source: NASA: The colour difference between the two lakes in the 1987 image was caused by the two lakes being separated by a thin strip of land. The two lakes merged into one in the mid-2000s when rising water levels submerged the strip of land.)

     

    (Image: October 9, 2021. Source: NASA)

    Way Ahead

    • The world needs to mitigate the climate change crisis by Policies and actions as described below
      • Net Zero targets
        • The countries need to push for net-zero rather than the targets of gross zeros as per IPCC’s 6th Assessment Report.
      • Food Security 
        • Farmers will need support to design and invest in locally appropriate agricultural practices.
      • Energy Security
        • New hydropower plants and grids will need to take into account the changing climate and water availability.
        • India can be a model in utilising Solar and other Renewable Energy.
      • Information dissemination
    • Early warning systems need to be improved and upgraded. 
    • More R&D and Investment 
      • Higher spending in discovering novel techniques for capacity building and infrastructure design can go miles in mitigating climate change.

    Source: DTE