A new study shows that climate change is a definite doom. It shows five dangerous tipping points may already have been passed due to the 1.1C of global heating caused by humanity to date.
At 1.5C of heating, the minimum rise now expected, four of the five tipping points move from being possible to likely, the analysis said.
In total, the researchers found evidence for 16 tipping points, with the final six requiring global heating of at least 2C to be triggered, according to the scientists’ estimations.
“The Earth may have left a ‘safe’ climate state beyond 1C global warming,” the researchers concluded, with the whole of human civilization developed in temperatures below this level. Passing one tipping point is often likely to help trigger others, producing cascades. But this is still being studied and was omitted, meaning the analysis may present the minimum danger.
Prof Johan Rockström, the director of the Potsdam Institute for Climate Impact Research, who was part of the study team, said: “The world is heading towards 2-3C of global warming.
“This sets Earth on course to cross multiple dangerous tipping points that will be disastrous for people across the world. To maintain liveable conditions on Earth and enable stable societies, we must do everything possible to prevent crossing tipping points.”
Dr. David Armstrong McKay at the University of Exeter, a lead author of the study, said: “It’s really worrying. There are grounds for grief, but there are also still grounds for hope.
“We’re not saying that, because we’re probably going to hit some tipping points, everything is lost and it’s game over. Every fraction of a degree that we stop beyond 1.5C reduces the likelihood of hitting more tipping points.”
The analysis, published in the journal Science, assessed more than 200 previous studies on past tipping points, climate observations, and modeling studies. A tipping point is when a temperature threshold is passed, leading to an inevitable change in a climate system, even if global heating ends.
The nine global tipping points identified are the collapse of the Greenland, west Antarctic, and two parts of the east Antarctic ice sheets, the partial and total destruction of Amoc, Amazon dieback, permafrost collapse, and winter sea ice loss in the Arctic.
The scientists define crossing a tipping point as “possible” when its minimum temperature threshold is passed and “likely” beyond the central threshold estimate.
At the Technical University of Munich, Prof Niklas Boers said: “The review is a timely update on the Earth’s potential tipping elements, and the threat of tipping events under further warming is real.”
A special IPCC report on climate tipping points was proposed in May by the Swiss government.
“Our new work provides compelling evidence that the world must radically accelerate decarbonizing the economy. To achieve that, we need to trigger positive social tipping points.”