Air monitoring station records largest-ever jump in atmospheric CO2

Carbon dioxide levels in the atmosphere as measured by a weather station at the Mauna Loa Observatory in Hawaii are projected to increase by 3.58 parts per million in 2024 – the largest jump since records began in 1958.

“We’re still going in the wrong direction,” says climate scientist Richard Bates At the Met Office, the UK weather service.

The record increase is partly due to CO2 emissions from fossil fuel burning and other human actions, such as cutting down forests, hitting a record high in 2024. Adding to this were the large number of wildfires, exacerbated by record-smashing global temperatures. El Niño weather pattern on top of long-term warming.

Bates estimates that atmospheric CO2 levels measured at Mauna Loa will increase by 2.26 parts per million (ppm) this year, with a margin of error of 0.56 ppm. This is well short of the 2024 record, but it will take us well beyond the last possible path to limiting global surface temperature rise to 1.5°C above pre-historic levels.

“You can think of this as another nail in the coffin of 1.5°C,” Bates says. “Now it is unlikely to disappear.”

CO2 levels in the atmosphere are the most important measure when it comes to climate change, as increasing atmospheric CO2 is the main factor driving both short- and long-term warming. The first ongoing measurements of CO2 levels were made at Mauna Loa.

“Because this station has the longest time record and is located far from the main anthropogenic and natural emissions and sinks of CO2, it is often used to represent global changes in CO2 concentrations,” richard engeln In the European Union’s Copernicus atmospheric monitoring service.

With observations from satellites, however, it is now possible to directly measure average global levels of atmospheric CO2. According to CAMS, this increases to 2.9 ppm in 2024. This is not a record, but it is one of the largest increases since satellite observations began.

“The reason for this large increase requires further investigation, but it would be a combination of the rebounding of emissions in large parts of the world after the Covid pandemic in combination with inter-variation in natural carbon sinks,” Engeln says. Carbon sinks refer to the oceans and ecosystems on land, which are soaking up about half of the CO2 emissions caused by humans.

It has long been predicted that, as the planet warms, less of this excess CO2 will be soaked up. “Is this the beginning of what’s concerning,” Bates says. “We don’t know.”

At Mauna Loa, the increase in CO2 due to a large number of wildfires in the Northern Hemisphere in 2024 is higher than the average global level, Bates says. It takes time for plumes of CO2 from sources like wildfires to mix evenly in the atmosphere around the world. “Fire emissions in the Northern Hemisphere were particularly large last year,” he says.

Although it now seems certain that global warming will exceed the 1.5°C limit, Bates thinks it was still right to set it as a target. “The Paris Agreement was carefully worded – to limit warming to 1.5% going forward. It was recognized early on that this would be challenging,” he says. “The idea was to have this stretch goal to inspire action, and I really think it was successful. This galvanized the action. ,