How could the global warming that our Earth experienced some 252 million years ago have wiped out nearly all life on our planet? Researchers may finally have the answer. And it should worry us.
The largest mass extinction in our Earth's history occurred about 252 million years ago. PaleontologistsPaleontologists Talk about the Permian-Triassic crisis. It is the period in which at least 90% of the land and marine species living on our planet disappeared. The reason: the great volcanic eruptions that occurred in present-day Siberia. BroadcastBroadcast From carbon dioxide (CO2)2)) Who accompanied them caused Global warmingGlobal warming Large size.
But this scenario has left experts baffled. According to them, it is not enough to explain such a massive extinction. “It was almost the end of life on Earth.”“The study's co-author, Yadong Sun, confirms in a press release From the University of Bristol. So what was this little extra something that, at that time, led to the downfall of so many species? Now researchers from the University of Bristol (UK) and the China University of Geosciences (Wuhan) have shed new light on this question.
Unstable climate and weather
Let us first point out that researchers were able to assess the extent of global warming from the Permian-Triassic period by studying IsotopesIsotopes Oxygen found in the fossilized teeth of tiny, extinct swimming creatures called conodonts. “Suddenly it's very hot everywhere.”Alexander Farnsworth, another co-author of the study published in the journal, says, sciences. “But our work shows that greenhouse gas emissions are not only warming much of the planet, they are also increasing weather and climate variability, making our Earth more difficult to live in.”
What the researchers are referring to is above all an intensification of events. El NiñoEl NiñoIn the context of global warming, this phenomenon is already noticeable. Stronger El Niño events than in the past are causing major changes in weather patterns. FallingFalling And temperatures. A wavewave to heatheat Which caused temperatures to rise 15 degrees Celsius above normal in North America a few weeks ago, for example.
The massive El Niño phenomenon is fueled by global warming.
“Fortunately, such events have only lasted for a year or two at a time so far. During the Permian-Triassic crisis, the El Niño lasted much longer, resulting in a decade droughtdrought Widely, followed by years ofFloodsFloodsBasically, climateclimate It was unstable and this made it very difficult for any species to adapt.“It is a very interesting discovery,” explains Paul Wignall, Professor of Palaeoecology at the University of Leeds.
Did you know?
Researchers from the University of Bristol (UK) and the Chinese University of Geosciences (Wuhan) recall that in the history of our Earth, mass extinctions have allowed life to reset and give evolution new directions. The Permian-Tertiary gave way to dinosaurs. The Cretaceous extinction gave rise to mammals and humans.
This massive El Niño was the origin of the Positive feedbackPositive feedback On the climate. Temperatures have risen again. Plants have withered. However, plants are essential because they remove carbon dioxide.2 appendix inAtmosphereAtmosphere Because they are the foundation Food chainFood chain. This may be why extinctions are starting to happen on dry lands. Especially since forest fires have become the norm during drought years caused by the massive El Niño phenomenon.
Our planet found itself in a state of crisis. The lands were burning, then the oceans began to overheat. “Life has no place to find refuge”Ultimately, only species that can migrate rapidly survive, says David Bond, a paleontologist at the University of Hull (UK). And few species can.
Let's remember that scientists still don't know how global warming caused by human activities will affect El Niño.No NinaNo NinaBut they warn that even a fraction of the disruption seen during the worst of times mass extinctionmass extinction The events that our land has witnessed will put us in very difficult living conditions.
