El Ni\u00f1o and mega ocean warming events were key in driving the largest extinction of life on planet Earth some 252 million years ago, according to new research <\/p>
El Ni\u00f1o and mega ocean warming events were key in driving the largest extinction of life on planet Earth some 252 million years ago, according to new research<\/strong><\/p> Over 250\u00a0million years ago, long before dinosaurs evolved, nine out every 10 plant and animal species were\u00a0wiped out in the largest extinction of life on planet Earth.<\/p> New research has shed light on how ocean warming El Ni\u00f1o<\/a> events were key in driving this mass extinction. The study, published in\u00a0Science<\/em>\u00a0and co-led by the University of Bristol and China University of Geosciences (Wuhan), reveals why the effects of rapid climate change in the Permian-Triassic warming were so devastating for all forms of life in the sea and on land.<\/p> The reasons behind this mass extinction have long been attributed to vast volcanic eruptions in what is now Siberia. The resulting CO2 emissions rapidly accelerated climate warming, causing widespread stagnation and the collapse of marine and terrestrial ecosystems.<\/p> But what caused life on land, including plants and usually resilient insects<\/a>, to suffer just as badly has remained a source of mystery.<\/p> \u201cIncreased weather and climate variability\u00a0de\u00a0it even more\u00a0\u2018wild\u2019\u00a0and difficult for life to survive.\u201d<\/em><\/p><\/blockquote> Co-lead author Dr Alexander Farnsworth, Senior Research Associate at the University of Bristol, said:\u00a0\u201cClimate warming alone cannot drive such devastating extinctions because, as we are seeing today, when the tropics become too hot, species migrate to cooler, higher latitudes. Our research has revealed that increased greenhouse gases don\u2019t just make the majority of the planet warmer, they also increased\u00a0weather and climate variability making it even more\u00a0\u2018wild\u2019\u00a0and difficult for life to survive.\u201d<\/p> The Permian-Triassic catastrophe shows the problem of global warming as not just a matter of it becoming unbearably hot, but also a case of conditions swinging wildly over decades.<\/p> \u201cMost life failed to adapt to these conditions, but thankfully a few things survived, without which we wouldn\u2019t be here today,\u201d\u00a0said co-lead author Professor Yadong Sun at China University of Geosciences, Wuhan.<\/p> \u201cIt was nearly, but not quite, the end of the life on Earth\u201d<\/em><\/p><\/blockquote> Part of the study involved analysing oxygen isotopes in the fossilised tooth material of tiny extinct organisms called conodonts. By studying the temperature record of conodonts from around the world, the researchers were able to show a remarkable collapse of temperature gradients in the low and mid latitudes.<\/p> \u201cEssentially, it got too hot everywhere,” said Dr Farnsworth, who used pioneering climate modelling to evaluate the findings. “The changes responsible for the climate patterns identified were profound because there were much more intense and prolonged El Ni\u00f1o events than witnessed today. Species were simply not equipped to adapt or evolve quickly enough.\u201d<\/p> In recent years El Ni\u00f1o<\/a> events have caused major changes in rainfall patterns and temperature. For example, the weather extremes that caused the June 2024 North American heatwave when temperatures were around 15\u00b0C hotter than normal. 2023-2024 was also one of the hottest years on record globally due to a strong El Ni\u00f1o in the Pacific, which was further exacerbated by increased human-induced CO2 driving catastrophic drought and fires around the world.<\/p> \u201cMass extinctions, although rare, are integral to the Earth\u2019s natural system\u201d<\/em><\/p><\/blockquote> \u201cFortunately such events so far have only lasted one to two years at a time. During the Permian-Triassic crisis, El Ni\u00f1o persisted for much longer resulting in a decade of widespread drought, followed by years of flooding. Basically, the climate was all over the place and that makes it very hard for any species to adapt,\u201d\u00a0co-author Paul Wignall, Professor of Palaeoenvironments at the University of Leeds<\/a>.<\/p> Researchers observed that the scale of the Permian-Triassic extinction was so massive because these Mega-El Ni\u00f1os created positive feedback on the climate, which led to incredibly warm conditions starting in the tropics and then beyond. This resulted in the dieback of vegetation. Plants are essential for removing CO2 from the atmosphere, and if they die so does one of the Earth’s mechanisms to stop CO2 building up in the atmosphere.<\/p> \u201cWhilst the oceans were initially shielded from the temperature rises, the mega-El Nino\u2019s caused temperatures on land to exceed most species thermal tolerances at rates so rapid that they could not adapt in time,\u201d\u00a0explained Dr Sun.<\/p> \u201cOnly species that could migrate quickly could survive, and there weren\u2019t many plants or animals that could do that.\u201d<\/p> Mass extinctions, although rare, are integral to the Earth\u2019s natural system, resetting life and evolution<\/a> along different paths.<\/p> \u201cThe Permo-Triassic mass extinction, although devastating, would ultimately see the rise of dinosaurs<\/a> becoming the dominant species thereafter as would the Cretaceous mass extinction<\/a> lead to the rise of mammals<\/a>, and humans,\u201d\u00a0Dr Farnsworth concluded.<\/p>Unstable conditions<\/h2>
Today’s climate<\/h2>
Death on land,\u00a0followed by the oceans<\/h2>