Our climate is changing, and the cause is our own emissions. To put those into perspective, new research estimates that atmospheric CO2 levels in 2021 will be 50% higher than the average value in the 18th century (the onset of the Industrial Revolution).
The Met Office, Britain’s national weather service, estimates in a new report that average annual CO2 levels this year (as measured at the Mauna Loa Observatory in Hawaii), will rise by roughly 2.29 ppm (parts per million) compared to 2020. That is around 150% of the concentration this gas registered in the 18th century, before industrial emissions started to output in significant quantities.
“Since CO2 stays in the atmosphere for a very long time, each year’s emissions add to those from previous years and cause the amount of CO2 in the atmosphere to keep increasing,” said Richard Betts, lead producer of the Met Office’s annual CO2 forecast.
The most worrying observation is that CO2 levels are still expected to rise in 2021 despite a significant drop in total emission levels due to the pandemic.
Mauna Loa is used as a gold-standard for the measurement of CO2 levels in the atmosphere. The site has been in operation monitoring this gas since 1958. These show seasonal variation , but they’re also influenced by local factors and geography, so having a single monitoring point in operation for so long makes the readings more reliable, as they can be easily compared to past readings.
Still, the news leaves us in an unenviable spot. According to the United Nations, emissions from energy, food production, transport and industry must drop by 7% per year every year throughout the next decade if we’re to meet the target of the Paris climate deal. This international deal aims to keep global warming “well below” 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial levels — ideally below 1.5 degrees Celsius.
We’ve only seen 1 degree Celsius of warming (compared to pre-industrial levels) so far, and yet, we have seen extreme weather events such as floods, droughts, and tropical storms pick up around the globe. The seas are also rising to meet us.
According to the Met Office, it took 200 years for atmospheric CO2 concentrations to rise 25% above pre-industrial levels; it only took an extra 30 to get to double that. It might take even less to double that figure yet again unless we take serious action — and do so quickly.
“Reversing this trend and slowing the atmospheric CO2 rise will need global emissions to reduce, and bringing them to a halt will need global emissions to be brought down to net zero.”