Humanity is experiencing an unprecedented threat with points of no return triggered by the climate crisis – 12/06/2023 – Environment

Humanity faces an “unprecedented” risk of reaching tipping points that could trigger a domino effect of irreversible planetary catastrophes, warns a scientific report released this Tuesday (5).

The announcement takes place during COP28, the UN climate change summit, in Dubai, in a year that is breaking monthly temperature records and is set to be the hottest year in history.

The report highlights 26 points of no return identified from evidence of changes, observational records and computational models. There are several elements that impact and destabilize systems at risk, such as deforestation; but for most, the climate crisis is one of them.

According to the document, even if the global temperature stopped rising now — the planet is 1.2°C warmer compared to the pre-industrial period — the collapse of some systems may already be underway.

This is likely the case for warm-water coral reefs. The collapse of four other systems also cannot be ruled out: the ice caps of Greenland and West Antarctica, the North Atlantic Gyre current, and parts of permafrost — broadly speaking, frozen layers of land.

Reaching points of no return could result in catastrophic impacts on humanity, the report says.

“The escalation of destabilization of the Earth system threatens to disrupt social cohesion, increase mental disorders and amplify radicalization and polarization. This has the potential to intensify violent conflicts, mass displacement and financial instability”, points out the document.

Tim Lenton, an Earth systems expert at the University of Exeter who led the report, told AFP that these tipping points represent a “threat to humanity of unprecedented magnitude.”

The study also details a series of points that could tip the scales in the other direction, such as the development of electric vehicles, renewable energy and the adoption of vegetarian diets.

“Imagine yourself lying in a chair tilted back, at that point of balance where a slight push can make a big difference,” Lenton said. “You might end up on your back on the floor or, if you’re lucky, on your feet again.”

On the edge

One of the main concerns is whether the West Antarctic and Greenland ice sheets will melt.

If this happens, sea levels could rise by two meters by 2100, exposing around 500 million people to a frequent risk of coastal flooding.

Greenland’s ice sheet has been thinning at such a rapid rate that it may be too late to reverse the process.

“Has the tipping point passed or could it stop? No one is sure,” Lenton said.

The other three most worrying tipping points, given their immediate potential, are the death of tropical coral reefs, the melting of permafrost, and an ocean current called the North Atlantic Gyre.

Another oceanic tipping point is the Atlantic Meridional Overturning Circulation (AMOC), a broad system that regulates global heat transfer from the tropics to the northern hemisphere.

According to the report, it would be likely — although unlikely — that AMOC would collapse this century.

This destabilizing change could result in large regions receiving much less rain, which would potentially halve the global area where wheat and corn are grown, the document indicates.

“If that happens, there will suddenly be a global food crisis and a similar water crisis, as the monsoons in the tropics will virtually disappear in India and West Africa. This will be a humanitarian catastrophe,” Lenton said.

“Terrible” risks

The recent wildfires in the Amazon and boreal forests of Canada are an indication that these systems are also at more immediate risk than previously thought.

Lenton compared the work of the more than 200 researchers who prepared the report, which is more than 400 pages long and titled “Global Tipping Points Report,” to that of risk assessors analyzing a new plane.

AMOC’s collapse would be like detecting something that could cause the plane to “fall out of the sky,” he said.

But there is no way to redesign the Earth to make it safer.

Another study author, Manjana Milkoreit from the University of Oslo, pointed out that “our global governance system is not adequate to deal with the threats that lie ahead and to implement urgently needed solutions.”

The authors call for inflection points to be included in the global balance — called Global Stocktake — discussed in the COP28 negotiations and in national goals to combat climate change. Sarah Das, a scientist at the Woods Hole Oceanographic Institution in the United States who was not involved in the report, said the data is now “clear as water.”

“The risks that humanity will surpass these inflection points […] are terrible, and the impact on human lives is potentially frightening,” he said.