Scientists warn that Earth is heading for a future mass extinction event where extreme temperatures make it nearly impossible for mammals, including humans, to survive. The study led by Dr. Alexander Farnsworth, a senior research associate at the University of Bristol, suggests a supercontinent called Pangea Ultima might form someday, driving temperatures to unlivable extremes.

How does a supercontinent spark mass extinction?

Published in the journal Nature Geoscience, it does present a notion that the continents of the Earth are soon to eventually move at a relatively slower rate and will then ultimately unite into one large supercontinent referred to as Pangea Ultima. This would present a new landmass, and according to the forecast of the researchers, the whole planet would become quite hot and dry. 

Dr. Farnsworth explained, "The newly-emerged supercontinent would effectively create a triple whammy, comprising the continentality effect, hotter sun, and more CO₂ in the atmosphere, of increasing heat for much of the planet."

This would isolate more land from the cooling influence of the ocean and, hence, increase inland temperatures. At the same time, a naturally aging sun would become brighter and release more energy, which would warm Earth even more. Also, tectonic shifts would cause volcanic activity to increase, emitting more carbon dioxide into the atmosphere and thus intensifying the heat.

A world too hot to sustain life

In this scenario, most areas are going to record temperature peaks as high as between 40 to 50 degrees Celsius. According to Dr. Farnsworth, in some zones, it is expected to shoot even higher with full-fledged moisture evaporation. That would be deadly for humans along with other species since "Humans—along with many other species—would expire due to their inability to shed this heat through sweat, cooling their bodies."

Food sources for mammals would also decline as extreme dryness sweeps across much of the land. The study calculates that once Pangea Ultima forms, as few as 8 percent to 16 percent of land areas may remain habitable for mammals.

Is this future avoidable?

The supercontinent, they add, is still hundreds of millions of years away. However, the study acts as a cautionary tale, underlining the need to deal with the climate challenges of today."It is vitally important not to lose sight of our current Climate Crisis, which is a result of human emissions of greenhouse gases," said Dr. Eunice Lo, co-author and Research Fellow in Climate Change and Health at the University of Bristol.

Though an uninhabitable Earth maybe 250 million years in the future, extreme temperatures are already affecting human health, says Dr. Lo. "This is why it is crucial to reach net-zero emissions as soon as possible," he added.

So far, the earth has witnessed five huge extinction events. Of the first one, 443 million years ago Ordovician-Silurian Extinction wiped away almost 85 percent of sea life. Another occurred Late Devonian about 360 million years ago, and the biggest ever was the Permian-Triassic Extinction popularly referred to as The Great Dying primarily due to volcanic actions, etc.

Around 200 million years ago, the Triassic-Jurassic Extinction made room for dinosaurs, while the infamous Cretaceous-Paleogene Extinction, which was caused by an asteroid impact, brought about the end of the reign of dinosaurs about 66 million years ago.

This work reminds scientists to urge policymakers for immediate climate change action. Current environmental problems must be overcome to safeguard the future of our planet.