Heat waves will make regions uninhabitable

“There are clear limits beyond which people exposed to extreme heat and humidity cannot survive,” the report said. File Photo

By Agence France-Presse October 12, 2022 

HEAT waves will become so extreme in certain regions of the world within decades that human life there will be unsustainable, the United Nations and the Red Cross said Monday (Tuesday in Manila).

Heat waves are predicted to "exceed human physiological and social limits" in the Sahel, the Horn of Africa and south and southwest Asia, with extreme events triggering "large-scale suffering and loss of life," the organizations said.

Heat wave catastrophes this year in countries like Somalia and Pakistan foreshadow a future with deadlier, more frequent and more intense heat-related humanitarian emergencies, they warned in a joint report.

The UN's Office for the Coordination of Humanitarian Affairs (OCHA) and the International Federation of Red Cross and Red Crescent Societies (IFRC) released the report in advance of next month's COP27 climate change summit in Egypt.

"We don't want to dramatize it, but clearly the data shows that it does lead toward a very bleak future," said IFRC Secretary-General Jagan Chapagain.

They said aggressive steps needed to be taken immediately to avert potentially recurrent heat disasters, listing steps that could mitigate the worst effects of extreme heat.

Limits of survival

"There are clear limits beyond which people exposed to extreme heat and humidity cannot survive," the report said.

"There are also likely to be levels of extreme heat beyond which societies may find it practically impossible to deliver effective adaptation for all.

"On current trajectories, heat waves could meet and exceed these physiological and social limits in the coming decades, including in regions such as the Sahel and south and southwest Asia."

It warned that the impact of this would be "large-scale suffering and loss of life, population movements and further entrenched inequality."

The report said extreme heat was a "silent killer," claiming thousands of lives each year as the deadliest weather-related hazard — and the dangers were set to grow at an "alarming rate" due to climate change.

According to a study cited by the report, the number of poor people living in extreme heat conditions in urban areas will jump by 700 percent by 2050, particularly in West Africa and Southeast Asia.

"Projected future death rates from extreme heat are staggeringly high — comparable in magnitude by the end of the century to all cancers or all infectious diseases — and staggeringly unequal," the report said.

Agricultural workers, children, the elderly, and pregnant and breastfeeding women are at higher risk of illness and death, the report claimed.

"As the climate crisis goes unchecked, extreme weather events, such as heat waves and floods, are hitting the most vulnerable people the hardest," said UN humanitarian chief Martin Griffiths.

"The humanitarian system is not equipped to handle crisis of this scale on our own."

'Previously unimaginable'

Chapagain urged countries at COP27 to invest in climate adaptation and mitigation in the regions most at risk.

CHA and the IFRC suggested five main steps to help combat the impact of extreme heat waves, 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 organizations testing more "thermally appropriate" emergency shelter and "cooling centers," while getting communities to alter their development planning to take 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.

If emissions of the greenhouse gases which cause climate change are not aggressively reduced, the world will face "previously unimaginable levels of extreme heat."

Coral Reefs rapidly die from marine heat waves

I love swimming and diving. In the Philippines, we have innumerable possibilities to swim and dive. Having fun while doing this wonderful sports. But during the last months, one observed the sad situation: yes, coral reefs rapidly die because of more and more marine heat waves all over the globe.

Scientists have published new findings on the impact of global warming on the world's coral reefs. They found that severe marine heat waves can completely destroy coral and threaten other marine species. Isn't that so very sad?
   
Scientists concluded that increasing sea temperatures can completely destroy coral reefs through a process called bleaching. Marine heat waves are killing coral reefs far quicker than scientists previously believed, this new study has found. From the news agencies AFP and dpa (German) on my desk this morning... .

Researchers from Australia, the UK and the US studied the impact of global warming in Australia's Great Barrier Reef and published their findings on Friday (yesterday, August 9, 2019) in the Current Biology Journal.

The scientists concluded that severe and frequent marine heat waves can destroy corals through a process called "bleaching."

Repeated "bleaching events" kill the colorful algae covering and nourishing the coral, thereby destroying the coral in a matter of months or years. If sea temperatures decrease, bleached corals can be revived.  If sea temperatures decrease. And if not??

The researchers also have evidence that the skeleton of corals, also an animal species, begins to decay within weeks of a marine heat wave. The degradation also puts at risk many other sea creatures that live in the sea coral.

"The severity of these heat wave events is beyond the bleaching process; it's actually a point where the coral animal itself is dying," said Tracy Ainsworth, a co-author of the study from the University of New South Wales.

Funny and discouraging at the same time: Great Barrier Reef: 'Last-chance' tourists flock to wonder as coral disappears. Try to explain it to your children. The size of the Great Barrier Reef covers an area larger than Italy and is one of earth's most bio-diverse ecosystems. Imagine, we are talking about the loss of a World Heritage Site.

The Great Barrier Reef, which is listed as a UNESCO World Heritage Site, is the world's biggest coral system. The reef covers an area larger than Italy and is one of earth's most biodiverse ecosystems.

However, the reef's Marine Park Authority predicts that if current greenhouse gas emissions are not curbed, the coral is projected to bleach twice a decade from 2035 and annually after 2044. In the past 20 years, the reef has suffered from four mass bleaching events due to global warming. Mass bleaching in 2016-2017 affected up to half of the coral in the 2,300-kilometer reef.

Study Links Heat Waves in Asia to Climate Change

The report, published in the Bulletin of the American Meteorological Society, investigates the causes of a wide variety of extreme weather and climate events from around the world in 2013. Titled "Explaining Extreme Events of 2013 from a Climate Perspective" the 84-page document examines the causes of 16 individual extreme events - including heat waves, rain, flood, droughts and storms - that occurred on four continents in 2013. 

Thirteen independent studies mentioned in the report - compiled by 92 scientists from around the globe – determined there was a link between extreme weather and the burning of fossil fuels. But while the authors found that human influence had substantially increased both the likelihood and severity of heat waves in places like Asia and Australia, it was more difficult to measure the influence of human activity on other events like droughts, heavy rain and storms.

Thomas Peterson, principal scientist at NOAA's National Climactic Data Center and one of the report's lead editors, says in an interview with  Deutsche Welle TV Berlin, that while scientists could not identify a linkage between human-caused global warming and some extreme weather events, the data gathered provides evidence that human activity has increased the intensity and likelihood of heat waves in Asian countries such as China, Japan and Korea.

Peterson: 'Human activity has influenced the strength of extreme weather or increased its likelihood'

Which extreme weather events did you focus on in Asia and why?

Thomas Peterson: Each of the four topics evaluated in Asia was selected by the author team for subjective reasons. Often because the event was of interest to them on a personal level, as it impacted them, their families and their friends. For instance, the report focuses on Japan, Korea and China which all experienced extremely hot summers in 2013.

The fourth topic focused on heavy rain in India. With an early arrival of monsoon-like atmospheric circulation in June, the heavy precipitation that occurred in northern India was a once-in-a-century event.

What were the key findings of the report?

The report found that long duration heat waves during the summer and prevailing warmth for annual conditions are becoming increasingly likely due to a warming planet, as much as 10 times more likely due to the current cumulative effects of human-induced climate change, as found for the Korean heat wave of summer 2013.

Extreme precipitation events of last year were found to have been much less influenced by human-induced climate change than extreme temperature events. Furthermore, prolonged cold waves have become much less likely, such that the severely cold 2013 winter over the United Kingdom was perhaps the most remarkable event of all those studied in 2013 - its probability of occurrence may have fallen 30-fold due to global warming alone.

However, there was no clear evidence of human influence on any of the three very intense storms examined, which included a surprising winter-like storm during autumn in the Pyrenees, an extreme blizzard across the US High Plains, and Cyclone 'Christian' that delivered damaging winds across northern Germany and southern Denmark.

To which extent did climate role play a role in extreme weather events in Asia last year?

All four events evaluated in Asia were found to indicate that human activity had influenced the strength of extreme weather or increased its likelihood. For instance, analyses of observed and simulated June precipitation provided evidence that human-caused climate change has increased the likelihood of much stronger precipitation in northern India, and made heat waves more likely to occur in Japan, Korea and Easter China.

How come human factors were found to have influenced some weather events, but not others? 

Natural variability was a prime cause of all events, just the randomness of the weather. For some of these events, in addition to the natural causes, human influence helped make the events stronger or more likely. But for some events in other regions, the analyses that scientists conducted could not identify a linkage. For a few events, greenhouse gases actually made the extreme event less likely.

Three independent studies which examined Pacific Sea surface temperatures and atmospheric anomalies, found some, but not conclusive, evidence for the impact of human-caused climate change on the ongoing rainfall deficit in the US state of California. For example, one paper found evidence that atmospheric pressure patterns related to the drought increased due to human causes, but their exact influence on the California drought remains uncertain.

So, in your view, which weather events are more likely to be influenced by human factors than others?

Three papers with different methodologies looking at the Chinese, Korean and Japanese heat waves reached the same conclusion. This is a very powerful message. If increases in greenhouse gases are making an event more likely, then it implies that we should expect events like that more often in the future.

The study examined the causes of 16 individual extreme weather events around the world in 2013.

If some extreme weather events could be linked directly to climate change, what does this tell us about the urgency to tackle the issue?

It tells us that climate change is not just in the future but, for example, for the people in eastern China, Korea and Japan, climate change is in their own backyards.

Thomas C. Peterson is President of World Meteorological Organization's Commission for Climatology and the Principal Scientist at the National Climatic Data Center of the National Oceanic and Atmospheric Administration (NOAA) in the United States.

(C) 2014 Deutsche Welle TV Berlin/Germany