Global warming like the one we are experiencing has already happened in the past!

56 million years ago, our Earth experienced an exceptional natural global warming. We are talking about greenhouse gas emissions associated with volcanism. And now researchers confirm that this warming was preceded by changes resembling those we are experiencing today. When our planet’s past opens a window to our future…

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[EN VIDÉO] Global warming: our planet is in unknown territory
In a preliminary version that only covers the first nine months of 2021 of its annual report on the state of the global climate, the World Meteorological Organization (WMO) confirms the global warming trend. For the first time in 20 years, the 1°C rise above pre-industrial averages has been surpassed. But above all, the report highlights the many extreme weather events that have occurred in 2021 and their consequences for the planet and humanity. © World Meteorological Organization

56 million years ago our Earth experienced significant global warming and fast. Scientists identify it as the Paleocene-Eocene Thermal Maximum (PETM). It was caused by the mass release greenhouse gas. The result of intense volcanic activity. But an international team of researchers is now showing that this exceptional warming was preceded by an event that strangely resembles the climate change we are experiencing today. From emissions from carbon dioxide (CO2) close to current levels have led to short-term warming and acidification of the oceans.

Until then, the sequence of environmental changes that led to PETM remained unclear. But scientists are now hoping the two events can provide them with useful insights into how our climate might evolve further with CO levels.2 in L’atmosphere which continues to increase.

Recall that evidence of environmental changes associated with PETM is recorded in sediment sailors. Resultabsorption the ocean a large amount of CO2 atmosphere. Analyzing the chemical composition shells from foraminifera — microscopic organisms preserved as fossils — researchers thus have access, in particular, to the temperature and pH of the oceans of the time. But they lacked fossils dating back to the beginning of PETM.

Two main possible warming scenarios

To overcome this difficulty, the researchers drilled along the East Coast of the United States. The area that once matched continental shelf small. With speed precipitation high due to proximity to the ground and some protection fromocean acidification.

Then they used an innovative technique. One laser as thick as a human hair to take microscopic plankton and send the evaporated particles into spectrometer from weight. Here’s how they were able to access previously unseen details. After analyzing just a few available shells, they estimated the acidity and therefore the carbon content of the oceans of that time. And their results are not subject to appeal. During the pre-PETM event, they are seeing an increase in carbon emissions on the order of what could be released today from human activity.

This is enough to draw closer parallels with anthropogenic climate change — even ice caps that exist today are making the climate more sensitive to warming. This is a harbinger of short duration seems more like what might happen if the current rate of carbon emissions were cut quickly. “This carbon could then be dissolved in the depths of the oceans”notes James Zahos, professor of geosciences, in University of California statement (United States). The pre-PETM event shows that it will take hundreds if not thousands of years for the climate system to return to its pre-industrial equilibrium.

But that’s nothing compared to the hundreds of thousands of years it took Earth’s climate to recover from PETM. Extreme warming that suggests what our future could be if we continued to emit CO2 at the current rate. And further proof that urgent action is needed to end our greenhouse gas.

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