The concentration of COtwo in the atmosphere reached in May a level 50% higher than that of the pre-industrial era and that had not been seen on Earth for about 4 million years, pointed out the NOAA (National Oceanic and Atmospheric Administration of the United States), this Friday. (3).
Human-caused global warming — with fossil fuel electricity production, transport, cement production or deforestation — is responsible for this phenomenon, the US agency said.
Annually, the month of May is usually the month with the highest levels of carbon dioxide.
In May 2022, the threshold of 420 parts per million (ppm), the unit of measurement used to quantify air pollution, was exceeded. In May 2021, this rate was 419 ppm, and in 2020, 417 ppm.
These measurements are established by the Mauna Loa observatory in Hawaii, ideally located at the height of a volcano, which allows it not to be influenced by local pollution.
Before the industrial revolution, the level of COtwo constantly hovered around 280 ppm during the roughly 6,000 years of human civilization that preceded it, according to NOAA.
The level reached today “is comparable” to what it was “between 4.1 and 4.5 million years ago, when CO levelstwo were close to or above 400 ppm,” the agency added in a statement.
Sea level at the time was 5 to 25 meters higher, enough that many of today’s large cities were submerged. In addition, vast forests occupied regions of the Arctic, according to studies.
the COtwo it is a greenhouse gas that traps heat, causing the planet to warm, and it persists in the atmosphere and ocean for thousands of years.
This warming already has dramatic consequences, NOAA said, including the multiplication of heat waves, droughts, fires or floods.
“Carbon dioxide is at levels our species has never known in the past, and it’s not something new,” said Pieter Tans, a NOAA scientist, according to the statement. “We’ve known this for half a century and we haven’t done anything significant. [sobre isso]. What does it take for us to wake up?”
