CO2 levels in the atmosphere are higher than any point since the evolution of man

"We do not know a planet like this."

It is the reaction of meteorologist Eric Holthaus to the news that carbon dioxide levels in the atmosphere have reached unparalleled heights throughout human existence – not in history.

According to data from the Mauna Loa Observatory in Hawaii, the concentration of CO2 in the atmosphere would be greater than 415 parts per million (ppm), which is far greater than what it was over the past 800,000 years since the evolution of homo sapiens.

Holthaus spotted the new record on Sunday when he was tweeted by the Scripps Institution of Oceanography, which measures daily CO2 levels at Mauna Loa, in collaboration with scientists from the National Oceanic and Atmospheric Administration.

Measurements have been ongoing since the launch of the program in 1958 by the late Charles David Keeling, to whom the Keeling Curve, chart representing the increase in CO2 concentration in the atmosphere, has been named.

"This is the first time in the history of humanity that the atmosphere of our planet has more than 415 ppm of CO2," said Holthaus in a widely shared tweet.

"Not only in history, nor since the invention of agriculture 10,000 years ago." Since then, modern man has existed there are millions of years. years, "added Holthaus.

During the Pliocene epoch, about 3 million years ago, when global temperatures were estimated to be 2 to 3 degrees Celsius higher than those of today, CO2 levels would have been reaches between 310 and 400 ppm.

At that time, the Arctic was covered with trees, not ice, and summer temperatures in the Far North are thought to have reached about 15 ° C (60 ° F). It was thought that the sea level during the Pliocene was 25 meters higher than today, or even more.

Devastating effects

High levels of CO2 in the atmosphere – caused by the burning of human fossils and the killing of forests by humans – prevent the Earth's natural cooling cycle from functioning, trapping heat near from the surface and causing an increase in global temperature with devastating effects.

The release of CO2 and other greenhouse gases has already resulted in a 1 ° C increase in global temperatures and we are probably stuck for a further rise, if the world's governments take no more immediate action.

According to 70 peer-reviewed climate studies, in a world where the temperature is 2 degrees higher, there will be 25% more hot days and additional heat waves, leading to major health risks and forest fires.

Worldwide, 37% of the population will be exposed to at least one major heat wave every five years, and the average duration of droughts will increase by four months, exposing some 388 million people to water scarcity. 5 million to severe droughts.

Floods and extreme weather events such as cyclones and typhoons will increase, forest fires become more frequent and crop yields will drop. Animal life will be devastated, with about 1 million species threatened with extinction. However, mosquitoes will flourish, which means that 27% of the planet will be exposed to malaria and other mosquito-borne diseases.

It's all at 2 degrees, a target that is becoming more and more optimistic. At a temperature rise of 3 or 4 degrees, we enter a phase of "greenhouse land" that could make many parts of the planet uninhabitable.

All this has been predicted for decades. We also know what needs to be done to put an end to it: drastic reduction of carbon emissions, reforestation and creation of carbon sinks, new carbon capture technologies and other innovations, or, in the words of the D & D Group. Intergovernmental experts on climate change, "rapid, profound and unprecedented changes in all aspects of society."

This can be done, and many are organizing to try to force their governments to act, but we are running out of time to avoid a world that we literally do not manage.