Extreme temperatures, radiation and collapse of food supply created by merging of continents would cause mass extinction
Mon 25 Sep 2023 16.00 BST
The formation of a supercontinent on Earth could wipe out humans and any other mammals that are still around in 250m years, according to a study.
The mass extinction would be caused primarily by heat stress as a result of greater volcanic activity that would put twice as much carbon dioxide into the atmosphere as current levels, an older sun that would emit more radiation and the extent of inland deserts in the tropics.
The supercontinent Pangea Ultima is expected to take shape when all the current continents merge together in the distant future. The paper, which was published on Monday in Nature Geoscience, is the first attempt to model how extreme the climate might become from that geological rearrangement.
Using a UK Met Office climate model and the University of Bristol supercomputer, the simulation also provided tectonic clues to past extinction events and data that could be of use to astronomers looking for other habitable planets.
In the era of Pangea Ultima, the temperature extremes are expected to be dramatic, with more humidity than now along the coasts and extremely arid conditions in the vast inland deserts. In this world, global temperatures could rise 15C (and up to 30C on land) above pre-industrial levels, which would return the world to the extreme heat it last went through in the Permian–Triassic era, 260m years ago, when more than 90% of species were eradicated. Protracted periods of heat in excess of 40C would be beyond the tolerance levels of many life forms.
Read more: https://www.theguardian.com/science/202 ... y-predicts
Credit: Dmitry Rukhlenko/Travel Photos/Alamy
