Some people still do not know that this global warming that we are experiencing today is the first time it has happened on Earth. However, there are many global warming and climate changes that have taken place on our planet throughout history. What is important to mention is that no global warming has previously occurred it has been in as little time as the current one. In other words, it is the human being who, with his polluting activities, is accelerating the process of global warming due to greenhouse gas emissions.
About 56 million years ago, the Earth suffered a rather abrupt global warming, for which it is known as the Paleocene-Eocene Thermal Maximum (MTPE, or PETM for its acronym in English). Do you want to know what caused such accentuated global warming?
Global warming 56 million years ago
At that time, human beings had not yet appeared, so we could not be the cause of such global warming. For those who think that this is natural and that the Earth suffers from time to time global warming that lead to climate changes, and that this is normal, it is not.
It is true that for millions of other years, the Earth has suffered from unexpected increases in temperatures and changes in climate, but it has done so with periods of thousands and thousands of years. In our current climate change, so it's only been about 250 years since the industrial revolution began and greenhouse gases began to be emitted.
About 56 million years ago the massive amount of carbon dioxide (CO2) emitted into the atmosphere dramatically raised temperatures on a global scale. The Paleocene-Eocene Thermal Maximum is undoubtedly the event related to the fastest and most extreme global warming that our planet has had naturally in the last 66 million years. Global warming lasted for about 150.000 years, and global temperatures increased by at least 5 degrees Celsius, an increase comparable to some of the predictions made for modern climate beyond the end of this century.
Reason for global warming
This global warming was very abrupt and was not caused by humans. So what could trigger such a rise in temperatures around the world? It has been suggested in the scientific community that it was caused by injecting carbon into the ocean and atmosphere, the ultimate trigger, the source of this carbon, and the total amount released, have so far been unknown.
However, where can such amounts of CO2 come from that the temperature of the entire planet increases by 5 ° C on average? An investigation carried out by the international team of Marcus Gutjahr, previously in the University of Southampton in the UK and now at GEOMAR (Helmholtz Center for Ocean Research) in Kiel, Germany gives the idea that it may have been due to the emission of gases from volcanic eruptions.
To this day, volcanoes are not responsible for the increase in the concentration of greenhouse gases, so it is normal to think that in the past neither. However, it must be taken into account that volcanic activity so many millions of years ago was much more frequent and intense than today.
Research and measurements
A combination of new geochemical measurements and global climate modeling was used to determine the reason for CO2 emissions, determining that this extreme global warming was caused by a geologically rapid doubling of atmospheric CO2. When we say the word fast we refer to a period less than 25.000 years (That is why we cannot compare this global warming with the current one, far from it), with volcanoes being the direct culprits of these emissions.
In addition, it can also be corroborated thanks to the fact that this time more or less coincided with the formation of enormous extensions of the oceanic bed of basalts, thanks to large amounts of lava that spread across the bottom. These occurred when Greenland began to separate from northwestern Europe, creating the North Atlantic Ocean.