The chances of a climate catastrophe are being ignored, scientists say

Experts are ignoring the worst possible climate change catastrophic scenarios, including the collapse of society or the potential extinction of humans, albeit unlikely, says a group of high-level scientists.

Eleven scientists from around the world ask the United Nations Intergovernmental Panel on Climate Change, the authoritative world organization of climate sciences, to make a special scientific report on “catastrophic climate change” to “focus on what is at stake in a worst case scenario”. In their perspective piece in the Proceedings of the National Academy of Sciences on Monday in the third sentence they raise the idea of ​​human extinction and the collapse of world society, calling it “a dangerously little explored topic”.

Scientists said they aren’t saying the worst will happen. They say the problem is that no one knows how likely or unlikely a “climate endgame” is and the world needs these calculations to fight global warming.

“I think it’s highly unlikely you’ll see anything close to extinction in the next century simply because humans are incredibly resilient,” said study lead author Luke Kemp at the University’s Center for the Study of Existential Risk. of Cambridge in England. “Even though we have a 1% chance of having a global catastrophe, which will end in the next century, that 1% is too high.”

Catastrophic climate scenarios “seem likely enough to warrant attention” and can lead to prevention and warning systems, Kemp said.

A good risk analysis considers both what is most likely and the worst that could happen, the study authors said. But due to the pushback of non-scientists who reject climate change, traditional climate science has focused on examining what is most likely and even disproportionate to low-temperature warming scenarios. that come close to international goals, said co-author Tim Lenton, director of the Global Systems Institute at the University of Exeter in England.

There is, Lenton said, “there is not enough emphasis on how things, the risks, the big risks, could conceivably go wrong.”

It’s like an airplane, Lenton said. It is extremely likely that it will land safely, but that is only because so much attention has been paid to calculate the worst case scenario and thus figure out how to avoid an accident. It only works if you research what could go wrong and that’s not done enough with climate change, he said.

“The stakes may be higher than we thought,” said Jonathan Overpeck, dean of the environment at the University of Michigan, who was not part of the study. He fears that the world “could stumble” on climate hazards he is unaware of.

When global scientific organizations look at climate change, they tend to look only at what is happening in the world: extreme weather conditionshigher temperaturesmelting ice capsrising sea and extinctions of plants and animals. But they don’t take enough account of how these reverberate in human societies and interact with existing problems – such as war, hunger and disease – the study’s authors said.

“If we don’t look at the intersecting risks, we will be painfully surprised,” said University of Washington public health and climate professor Kristie Ebi, a co-author who like Lenton has been a part of the United Nations global climate assessments.

It was a mistake made by health workers prior to COVID-19 in evaluating possible pandemics, Ebi said. They talked about the spread of the disease, but not about blockages, supply chain problems and spiraling economies.

The authors of the study said they are concerned about the collapse of society – war, famine, economic crises – related to climate change rather than the physical changes of the Earth itself.

Climate scientists and outside risk experts were both welcome and wary of focusing on the worst of the worst, even though many reject talk of climate fate..

“I don’t think civilization as we know it will come out this century,” University of Victoria climate scientist Andrew Weaver, a former British Columbia lawmaker for the Green Party, said in an email. “Resilient humans will survive, but our societies that have urbanized and are supported by rural agriculture will not.”

Climate scientist Zeke Hausfather of technology company Stripe and Berkeley Earth has criticized climate scientists in the past for using future scenarios of soaring carbon pollution when the world is no longer on those roads for faster warming. However, he said it makes sense to look at catastrophic scenarios “as long as we are careful not to confuse the worst case with the most likely outcome”.

Talking about the extinction of humans is not “a very effective communication device,” said Kim Cobb, a climate scientist at Brown University. “People tend to immediately say, well, it’s just, you know, waving or doing apocalypse.”

What is happening before the extinction is bad enough, he said.

Co-author Tim Lenton said worst-case research could find nothing to worry about: “Perhaps a number of these negative scenarios can be completely ruled out. Well, it’s actually really worth taking your time to do this. Then we should all rejoice a little. “


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