Levels of important heat-trapping gases in the atmosphere reached historic highs last year and are rising at a near-record pace, according to the U.S. National Oceanic and Atmospheric Administration. Carbon dioxide, the most important and abundant of the human-caused greenhouse gases, rose in 2023 by the third-highest amount in 65 years of record-keeping, NOAA said Friday. Scientists are also concerned about the rapid rise in atmospheric levels of methane, a shorter-lived but more potent heat-trapping gas. Both have jumped by 5.5 % over the past decade.

The 2.8 parts per million increase in atmospheric carbon dioxide from January 2023 to December was not as large as the spikes in 2014 and 2015, but it was larger than in any other year since accurate records began in 1959. The average carbon dioxide level in 2023 was 419.3 parts per million, 50 % higher than in pre-industrial times. (by Seth Borenstein, more at phys.org)