Atmospheric Carbon Levels to Hit Unwelcome 2021 Milestone

(Bloomberg) -- Global atmospheric carbon dioxide levels will be 50% higher this year than before the start of the Industrial Revolution, according to forecasts that show the rapid pace at which humans are polluting the atmosphere.

It took more than 200 years for the concentration of CO2 in the atmosphere to grow 25% by the end of the 1980s. The majority of the damage has been wrought in the last 30 years as the pace of deforestation and burning of fossil fuels picked up rapidly.

The concentration of CO2 in the atmosphere is set to exceed 417 parts per million for several weeks this year, the U.K.’s Met Office said in a report released on Friday. CO2 concentrations vary throughout the year, peaking in May.

While the pandemic caused a sharp drop in greenhouse gas emissions in 2020, CO2 hangs around in the atmosphere for hundreds of years. That means any emissions pumped into the air will have an effect for generations.

Measurements are collected at the Mauna Loa Observatory in Hawaii, where David Keeling first took records in 1958 and subsequently lent his name to the Keeling curve which shows the impact of human activity on climate change.

The Met Office forecasts that the rise in CO2 will also be slightly smaller in 2021 because of the La Nina weather factor, which encourages tropical forests to grow and soak up more emissions.

“Reversing this trend and slowing the atmospheric CO2 rise will need global emissions to reduce,” said Professor Richard Betts, who leads the production of the Met Office’s annual CO2 forecast.

“Bringing them to a halt will need global emissions to be brought down to net zero. This needs to happen within about the next 30 years if global warming is to be limited to 1.5°C,” he said.

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