A recent study has painted a concerning picture of Earth's distant future, suggesting that extreme heat could lead to a mass extinction event, potentially ending the reign of humans and mammals. Led by Dr. Alexander Farnsworth, a Senior Research Associate at the University of Bristol, the research explores the formation of a new supercontinent, Pangea Ultima, and its catastrophic impacts on life.
According to scientists, the Earth's tectonic plates are moving in a way that will eventually lead to a single, massive landmass. This supercontinent, named Pangea Ultima, would alter the planet's climate significantly. Using advanced climate models, the study published in *Nature Geoscience* demonstrates how the new configuration could result in extreme heat and arid conditions that challenge most life forms.
Dr. Farnsworth highlights a "triple whammy" of factors that would drive the extreme temperatures. Firstly, the supercontinent's formation would increase the continentality effect, with more land far from the cooling influence of the ocean. Secondly, the sun's gradual increase in brightness over millions of years would heighten warming. Finally, increased volcanic activity due to tectonic shifts would raise atmospheric carbon dioxide levels, trapping more heat.
"The newly-emerged supercontinent would create a climate that could be intolerable for most species," Dr. Farnsworth explained. "Humans and other mammals would face extreme temperatures of 40-50°C (104-122°F) with dangerous humidity levels that prevent cooling through sweating."
While mammals have historically adapted to climate shifts, prolonged exposure to extreme heat could exceed their ability to survive. The study suggests that only 8-16% of land on the supercontinent would remain habitable. As heat and aridity dominate most regions, food and water sources would become scarce, posing further survival challenges for humans and wildlife alike.
To estimate future atmospheric conditions, researchers used models of tectonic movement and ocean chemistry. Professor Benjamin Mills of the University of Leeds noted that carbon dioxide levels could eventually double from today's levels of around 400 parts per million. This rise, coupled with a more radiant sun, would push temperatures to unprecedented highs.
The study also sheds light on the potential habitability of other planets. "This research shows that a world within a star's habitable zone may not actually be suitable for human life if continental arrangements resemble a supercontinent like Pangea Ultima," Dr. Farnsworth noted. This insight could refine our understanding of habitability on exoplanets, helping scientists assess their climates.
Although this scenario is millions of years in the future, co-author Dr. Eunice Lo emphasized the urgency of the current climate crisis. "We shouldn't overlook our current Climate Crisis, which is a direct result of human-generated greenhouse gases," she said. "The extreme heat we see today is already impacting health. Achieving net-zero emissions is crucial."