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Heatwaves will become so extreme in certain regions of the world within decades that human life there will be unsustainable, say UN, Red Cross.

GENEVA A HOW United Nations Red Cross report into climate change alludes to certain parts of the world becoming so hot within a matter of decades that human beings will be unable to survive there.

The bleak joint report predicts extreme heatwaves could become so fierce that they exceed human physiological and social limits in parts of Latin America, central Africa and south and southwest Asia.

 The world's lowest-income countries- those least responsible for climate change-are already experiencing a disproportionate increase in extreme heat, as was witnessed this year with the heatwave catastrophes in Somalia and Pakistan

The report is published by the UN's Office for the Coordination of Humanitarian Affairs (OCHA) and the International Federation of Red Cross and Red Crescent Societies (IFRC) ahead of Novembers COP27 climate change summit in Egypt.

What can be done?

IFRC secretary-general Jagan Chapagain urged countries at COP27 to: invest in climate adaptation and mitigation in the regions most at risk.

OCHA and the IFRC suggested five main steps to help combat the impact of extreme heatwaves, including: providing early information to help people and authorities react in time and finding new ways of financing local-level action.

They also included humanitarian organisations testing more "thermally-appropriate emergency shelter and "cooling centres, while getting communities to alter their development planning to account of likely extreme heat impacts.

OCHA and the IFRC said there were limits to extreme heat adaptation measures. Some, such as increasing energy-intensive air conditioning, are costly, environmentally unsustainable and contribute themselves to climate change. The report concludes that if greenhouse gas emissions, which cause climate change, are not aggressively reduced now, the world will face previously unimaginable levels of extreme heat.

Picture Credit : Google 

Alaska's snow crabs are named so for their love of cold water, which they inhabit. But, due to the heatwaves in 2018 and 2019, their habitats were not cold enough, and this is suspected to be the "key culprit in the mass die-off. The warmer are believed to have affected the species in more ways than one.

Recently, the Alaska Department of Fish and Game announced that the Bering Sea snow crab season will stay closed for catching during 2022-23 to conserve and rebuild the species. (Though they are found in a couple of other places too, it is in Bering Sea that these crabs are abundant and also grow to reach "fishable sizes".) The announcement follows an annual survey by the National Oceanic and Atmospheric Administration, which discovered that the crustacean numbers "fell to about 1.9 billion in 2022, down from 11.7 billion in 2018", a reduction of nearly 85%. What caused this dramatic loss, and how will closing the season help the species? Come, let's find out.

Alaska's snow crabs are named so for their love of cold water, which they inhabit. But, due to the heatwaves in 2018 and 2019, their habitats were not cold enough, and this is suspected to be the "key culprit' in the mass die-off. The warmer temperatures are believed to have affected the species in more ways than one. For instance, studies "have pointed toward a higher prevalence of Bitter Crab Disease as the temperature heats up". Further, unlike in cold waters, these crabs "need more energy to stay alive" in warmer waters, causing them "metabolic stress", which likely led to limited movement, and eventual starvation. Apart from this, young crabs require low temperatures of water where their mobility is high, helping them evade predation. When the waters warm, they slow down, and their chances of being targeted by their major predator- the Pacific cod - are higher. 5

However, it is interesting to note that a marine biologist has said that the current predicament was linked more to climate change rather than to overfishing because fishing "removes only large adult males" but the decline in population appears across all sizes of snow crabs. If that's the case, what explains closing the area for catching these crabs?

Because, the temperature of the water has now returned to normal; closing will help the reproduce and recover. Comfortingly, "this years survey saw significant increases in the immature crabs compared to last year".

Picture Credit : Google