Climate Change

‘Permanently frozen’ Himalayan areas at severe drought risk due to global warming

Report warns of longer-lasting droughts than natural land, urban areas; Will result in less water for rivers

 
By Rohini Krishnamurthy
Published: Thursday 29 September 2022
Severe drought may sweep more than 90% of permanent snow and ice regions. Photo: Wikimedia Commons_

Climate change is likely to trigger severe drought in India’s permanent snow and ice regions, impacting long-term water storage in the Himalayas, a new study has warned. For countries like Egypt, severe droughts may become the new norm. 

Severe drought may sweep more than 90 per cent of these areas if the global mean temperature exceeds 3 degrees Celsius above the pre-industrial era, the paper published in journal Climate Change stated.

These areas may also face prolonged droughts. Areas of permanent snow and ice are likely to have droughts for roughly three years in the 2 degrees Celsius warming scenario. It can go up to four years in 4 degrees Celsius warming scenario, the findings showed.


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The country’s permanent snow and ice regions face a higher drought risk than agricultural, natural land and urban areas, the researchers found.

“The higher probability and length of drought in permanent snow and ice fields means that these snow and ice fields are not replenished,” Jeff Price from the Tyndall Centre for Climate Change Research at the University of East Anglia and the lead author of the study, told Down To Earth.

This, along with a reduced amount of available annual snow and ice for melting, results in low water availability in rivers fed by the snow and ice fields, he added.

Price and his colleagues gauged the drought risk in India and five other nations — Brazil, China, Egypt, Ethiopia, and Ghana — under different global warming scenarios from 1.5 to 4 degrees Celsius.

The team used climate models, drought statistics, population growth projections, and satellite data on land cover for their analysis.

Drought probability is projected to increase in all countries relative to 1961–1990, the paper stated.

In India, drought probability will likely increase slightly under 1.5 degrees Celsius, double at 2 degrees Celsius, increase to 14 per cent at 3 degrees Celsius and rise nearly 20 per cent at 4 degrees Celsius of warming.

In Brazil and China, the probability is projected to triple, quadruple, increase 30-40 per cent, and rise to nearly 50 per cent under 1.5 degrees, 2 degrees, 3 degrees and 4 degrees Celsius of warming, respectively.


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For Ethiopia and Ghana, the probability will nearly double, double, increase 20-23 per cent and 27-30 per cent under the 1.5 degrees, 2 degrees, 3 degrees and 4 degrees Celsius warming scenario.

Egypt will face a higher toll. It will see a substantial increase at 1.5 degrees, 90 per cent at 2 degrees and nearly 100 per cent at both 3 degrees and 4 degrees Celsius.

Egypt, known for its arid conditions, is highly vulnerable to water scarcity, droughts, and rising sea levels, according to the International Monetary Fund, a United Nations agency.

As for duration, droughts lasting two months and longer are projected to occur in Brazil, China, Ethiopia, and Ghana in a 1.5 degrees Celsius warming scenario, the study showed.

“India nears this mark, and in Egypt, severe drought begins to become the new norm,” the paper read.

In a 2 degrees Celsius warming scenario, three-year-long droughts may occur in all countries except India.


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Droughts lasting 4–5 years may occur in a 3 degrees Celsius warming scenario, the study showed. Brazil and China, it added, may have to brace for severe droughts lasting five years and longer in a 4 degrees Celsius warming scenario.

The agricultural sector of all six countries will likely face water stress, the researchers said.

“But meeting the Paris Accords could have major benefits in reducing severe drought risk in these six countries,” Rachel Warren, Professor at the University of East Anglia, said in a statement.

This, the expert added, requires urgent global-scale action to stop deforestation (including in the Amazon) in this decade.

Decarbonising the energy system to keep global net zero greenhouse gas emissions by 2050 within reach, she highlighted.

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