Climate researchers from France fear the effects of global warming by 2100 will be more severe than previously thought. Worst-case-scenario models suggest global temperatures will rise by 6C to 7C degrees by the end of the century. The French National Center for Scientific Research (CNRS) warned 2012 climate models underestimated the disastrous effect of human-induced greenhouse gas emissions. More than 100 scientists representing a wide field of scientific backgrounds were involved in the dire climate study.
Although the exact reasons for the disparity in results are unknown, scientists in part attribute some outcomes to “rapid economic growth driven by fossil fuels”.
The CNRS said in a release: “Simulations with the two new French models, as well as with models from other countries that are already available, predict that by 2100 warming will be more severe than that forecast in previous versions in 2012, especially for the most pessimistic emission scenarios.
“This could be explained by a more pronounced climate response to the increase in human-induced greenhouse gases than in the 2012 simulations.
“However, the reasons for this increased sensitivity and the degree of confidence to be attributed have yet to be assessed.”
The climate models required the use of France’s most powerful supercomputers, generating 20 petabytes of data after 500 million computing hours.
To prevent the catastrophic impact of climate change, scientists estimate temperature need to be limited to 1.5C of warming above pre-industrial levels.
Warming of just 1.5C is expected to raise average surface temperatures, increase the number of heatwaves, accelerate the melting of the ice caps and disrupt the frequency of rainfall.
The melting of the ice caps, in particular, threatens shorelines around the globe with high sea levels and the loss of land.
As little as 10 inches to 30 inches of sea-level rise can put more than 10 million people at risk.
The IPCC states: “Overshooting poses large risks for natural and human systems, especially if the temperature at peak warming is high, because some risks may be long-lasting and irreversible, such as the loss of some ecosystems.”
Researchers in France believe a strong investment in sustainable development can help mitigate some of the effects of climate change.
The CNRS said: “These results were obtained thanks to improvements made to climate models since the previous programme.
“Their spatial resolution is greater, the modelling of the different physical compartments of the climate system – ocean, atmosphere, land surfaces, ice, etc. – is more advanced and ongoing assessments show that the French models simulate observed climate characteristics better than older versions.”
The CNRS study was carried out with Meteo France and the European Center for Research and Advanced Training in Scientific Computing (CERFACS).
The findings were presented as part of the World Climate Research Programme (CMIP6).
The findings will also inform the conclusions of the United Nation’s next IPCC climate change report in 2021.