Atmospheric carbon the concentration of dioxide (CO2) will hover past a frightening threshold this year and exceed 417 parts per. million (ppm) – an increase of 50% since the beginning of widespread industrial activity in the 18th century.
The forecast comes from the Met Office, the national meteorological service for the UK, which used data collected at the Mauna Loa Observatory in Hawaii. Although there was a slight decrease in global greenhouse gas emissions in 2020 due to COVID-19 pandemic and the power La Niña event (a weather pattern in the Pacific that usually lowers global carbon emissions), it was not enough to offset previous increases.
“As CO2 stays in the atmosphere for a very long time, every year emissions are added to them from previous years and cause the amount of CO2 in the atmosphere to continue to rise,”
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The concentration of CO2 in the atmosphere follows predictable seasonal variations. Levels peak in May and then fall in summer as plants grow across the northern hemisphere and absorb carbon (with photosynthesis) before rising again from September onwards.
Although total CO2 emissions worldwide by 2020 had fallen by 7% from previous years, emissions have almost returned to pre-pandemic levels, according to the Met Office.
The current La Niña event, which has caused unusually cool weather since mid-2020, is also expected to reduce the increase in CO2 this year. This is due to a temporary increase in the amount of carbon stored in ecosystems such as tropical forests, which grow faster under cooler conditions.
However, that is still not enough to stop the planet from reaching the ominous CO2 milestone this year.
The Mauna Loa Observatory holds the longest continuous record of atmospheric CO2 concentrations in the world.
Since climate scientist Charles David Keeling started these records in 1958, scientists have used the data to track atmospheric CO2 levels using the Keeling Curve, a graph that has become an iconic symbol of humanity’s growing influence on the global climate system.
This means that we have a lot of work to do to meet the International Panel on Climate Change’s goal of limiting global warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial levels.
“To reverse this trend and slow the atmospheric rise in CO2 will need global emissions to reduce, and if one stops them, global emissions must be brought down to net zero,” Betts said. “This must happen within the next 30 years if global warming is to be limited to 1.5 degrees Celsius.”
With Office released CO2 forecast for 2021 on Jan. 8.
Originally published on WordsSideKick.com.