New research shows that atmospheric CO2 concentrations in May reached a threshold of 420 ppm, 50% higher than in pre-industrial times.
This is the highest concentration not seen in about 4 million years, the National Oceanic and Atmospheric Administration (NOAA) emphasized on June 3. Measurements were taken at the Mauna Loa Observatory in Hawaii, which ideally sits on top of a volcano, allowing it to escape the possible effects of local pollution.
Before the “industrial revolution”, carbon dioxide (CO2) concentrations had remained stable at 280 parts per million (ppm) for about 6,000 years of human civilization. Current levels of 420 ppm are comparable to concentrations estimated above 400 ppm 4.1 to 4.5 million years ago. At that time, sea level was 5 to 25 m higher than now, high enough to engulf many major cities today.
A CO2-emitting thermal power plant near a residential area in Dadri, India. Image: AFP
Entering the industrial age, humans have released large amounts of CO2 into the air through the use of fossil fuels in power generation, transportation, cement production, and deforestation.
CO2 is a greenhouse gas that traps heat, gradually causing global warming. It remains in the atmosphere and oceans for thousands of years.
NOAA notes that the greenhouse effect has had serious consequences, including an increase in both the intensity and frequency of heat waves, droughts, fires and floods.
“The carbon dioxide levels are at levels we’ve never experienced before, but that’s nothing new. We’ve known about this for half a century but there’s nothing we can do to change it,” he said. scientist Pieter Tans at the Full Monitoring Laboratory said.
Doan Duong (Follow AFP)
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