Two children walk past the dry bed of the Jialing River, which flows through the southwestern Chinese city of Chongqing.Image: AP COLOR CHINA PHOTO
Mar 25, 2026, 9:32 p.mMar 25, 2026, 9:32 p.m
Climate science traditionally communicates worst-case scenarios using warming levels: What will the world look like at 3 or 4 degrees above pre-industrial levels? So the average temperature for the years 1850-1900. This serves as a zero point to measure the extent of global warming since fossil fuels began to be burned.
A study published on Wednesday in Specialist journal “Nature” appeared, calls this view into question. It shows that extreme climatic consequences can occur even at temperatures as low as two degrees – the value that cannot be exceeded according to the Paris Climate Agreement.
Higher temperatures can also lead to flooding.Image: keystone
The problem with the model mean
So far, the so-called worst-case climate has mostly been described as an average of several climate model simulations at a high level of warming – around three or four degrees. The research team led by Dr. Emanuele Bevacqua from the Helmholtz Center for Environmental Research in Leipzig and Dr. Jakob Zscheischler from the University of Bern.
Instead of just looking at the global average, their method analyzes worst-case scenarios for critical regions such as important growing areas or densely populated cities. This shows that even a warming of two degrees could have consequences similar to those previously assumed for four degrees.
A forest fire reached the site of a coal-fired power plant in southwestern Turkey, requiring evacuations by boat and car.Image: AP
Droughts, floods and the risk of forest fires
Some models for deep temperature increases are already predicting droughts in important growing regions, flooding in dense cities due to heavy rain and a higher risk of forest fires than research previously expected, even with a significantly greater increase in temperature – an alarming finding given the fact that emissions from forest fires have already increased by 60 percent in the last twenty years.
The uncertainties between the climate models – and not the question of whether the earth will be two or four degrees warmer – are the decisive factor for the actual level of risk. Even if the international community… Paris climate goals achieved, this is no guarantee against extreme climate impacts. The study therefore advocates including extreme scenarios in risk planning in addition to the most likely scenario.