In a staggering 250 million years from now, living on the coast may resemble being trapped in a sweltering, humid plastic bag. Surprisingly, this would be considered the best habitat on Earth. Meanwhile, inland areas would experience temperatures hotter than the scorching summers in the Gobi Desert and could be up to four times drier. This is the projected life on Pangea Ultima, a future supercontinent predicted by an international team of scientists.
Alexander Farnsworth, a climatologist at the University of Bristol and the lead author of a newly published paper in Nature Geoscience, describes this future world as extremely inhospitable. According to their calculations, the continents will collide once again in 250 million years, leading to an unbearably hot Earth, rendering much of the land uninhabitable, and causing mass extinction of land mammals. Farnsworth grimly sums it up as a “very bleak” scenario.
The prediction of a future supercontinent is not the surprising aspect of this study. Over long periods of time, continents gradually shift their positions, which can dramatically transform the appearance of the Earth. Damian Nance, a geologist and supercontinent-formation expert at Ohio University, explains that multiple supercontinents have existed in Earth’s history. The most well-known is Pangea, but scientists believe there have been others, such as Rodinia roughly 1 billion years ago and Nuna several hundred million years before that.
The shape of the next supercontinent, however, has been a subject of debate among geologists. One theory suggests that the Americas will drift westward across the Pacific, collide with Asia, and settle near the North Pole, forming “Amasia”. Another theory proposes the squeezing out of the Atlantic Ocean, reuniting the Americas, Africa, and Eurasia along the equator. Pangea Ultima, first described in 2003 by paleogeographer Christopher Scotese (a co-author of the current study), would be the end result of this fusion.
Scotese, Farnsworth, and their colleagues describe life on Pangea Ultima in their paper. The supercontinent, they assert, would suffer from its vast size. Without the temperature-regulating influence of oceans except on the coasts, land temperatures would rise by a staggering 14 degrees Celsius. To put this in perspective, the Paris Agreement aims to limit global temperature increase to 1.5 degrees Celsius above preindustrial levels. The continent’s interior would become a scorching desert, with occasional shrublands and expansive barren stretches. Volcanic eruptions and other geological disturbances would release immense amounts of carbon dioxide, more than doubling current levels and ultimately leading to an 11-degree Celsius increase in global temperature. Additionally, based on previous projections, the team anticipates the sun’s brightness to amplify by 2.5 percent, intensifying the heat reaching the already sweltering Earth.
The model does not factor in all the variables that could influence Pangea Ultima’s climate. Notably, it does not account for additional warming caused by human greenhouse gas emissions. Elena Shevliakova, a climate modeler at NOAA’s Geophysical Fluid Dynamics Laboratory, observes that the model also overlooks potential cooling factors like ice sheets, lakes, and straits. She describes this as the worst-case scenario possible. Nonetheless, the authors argue that sustained temperatures as high as those projected over millions of years could pose a threat to all life on Earth. They predict that only 8 percent of the planet’s land might remain habitable for mammals, should they survive that long.
However, other researchers caution against taking these predictions as definitive. Daniel Schrag, a geologist at Harvard, believes that the formation of Pangea Ultima (which he finds uncertain) does not guarantee the survival of mammals. Mammals have existed for a mere 175 million years, and their continued presence is not assured. Furthermore, life, including mammals, has demonstrated its ability to adapt and evolve in new environments.
While making claims about the state of the world so far into the future may seem speculative, other experts find value in this paper. Shevliakova suggests that long-term projections serve as a stress test for climate projection models. In this study, researchers applied a UK Meteorological Office model, commonly used for near-term climate change projections, to a vastly different time period and question. The fact that the model performed as expected so far into the future exemplifies the robustness of current climate change research and methods, Shevliakova asserts.
Nance, the Ohio University geologist, highlights that long-term predictions can help refine forecasts for the next 50 to 100 years. They allow scientists to consider various processes besides fossil fuel burning that could impact atmospheric carbon dioxide levels, both increasing and decreasing them, and understand the time frame associated with these processes.
Whether the far-future world turns out to be more or less dire than predicted, these potential uses of the study may be its most important lesson. After all, it is impossible for us to verify the accuracy of Farnsworth and his team’s projections in 250 million years, as humorously emphasized by Shevliakova.
Denial of responsibility! Vigour Times is an automatic aggregator of Global media. In each content, the hyperlink to the primary source is specified. All trademarks belong to their rightful owners, and all materials to their authors. For any complaint, please reach us at – [email protected]. We will take necessary action within 24 hours.
