Mauna Loa Observatory
The Mauna Loa Observatory. Courtesy NOAA

Carbon dioxide levels measured on Mauna Loa in Hawaii set a new record of 424 parts per million in May, continuing the steady climb in greenhouse gas concentration in the atmosphere, the Scripps Institution of Oceanography reported Monday.

The latest measurement by the research station at 11,000 feet on the north slope of the volcano is 3 parts per million higher the figure recorded in May 2022.

Carbon dioxide levels in the atmosphere are now more than 50% higher than they were before the onset of the industrial era, Scripps said.

“Sadly we’re setting a new record,” said geoscientist Ralph Keeling, who oversees the iconic Keeling Curve record established by his father 65 years ago.

“What we’d like to see is the curve plateauing and even falling because carbon dioxide as high as 420 or 425 parts per million is not good. It shows as much as we’ve done to mitigate and reduce emissions, we still have a long way to go,” he said.

Carbon dioxide is generated by burning fossil fuels for transportation and electrical generation, by cement manufacturing, deforestation, agriculture and many other human activities. Like other greenhouse gases, carbon dioxide traps heat radiating from the planet’s surface that would otherwise escape into space, causing global warming.

Keeling Curve graph
The Keeling Curve. Courtesy Scripps Institution of Oceanography

“Every year we see carbon dioxide levels in our atmosphere increase as a direct result of human activity,” said NOAA Administrator Rick Spinrad. “Every year, we see the impacts of climate change in the heat waves, droughts, flooding, wildfires and storms happening all around us.”

“While we will have to adapt to the climate impacts we cannot avoid, we must expend every effort to slash carbon pollution and safeguard this planet and the life that calls it home,” he said.

This year’s measurement in May, the month when carbon dioxide peaks in the northern hemisphere, follows restoration of power to the research station in March after an eruption in December. In the interim, carbon dioxide was measured atop the nearby Mauna Kea volcano.

Scripps has been measuring the carbon dioxide level at Mauna Loa since 1958.

Chris Jennewein is Editor & Publisher of Times of San Diego.