1089. Climate Records for 2023

The State of the Climate in 2023 was published in the Bulletin of the American Meteorological Society (BAMS), confirming that the concentration of greenhouse gases in the atmosphere, the global average temperature on land and in the sea, sea level, and ocean heat content have reached record highs. 
 

Atmospheric concentrations of carbon dioxide, methane, and nitrous oxide, the three major greenhouse gases, reached new highs in 2023. The average annual increase in global carbon dioxide concentrations was 0.6 ± 0.1 ppm in the early 1960s, but averaged 2.5 ppm per year in the decade from 2014 to 2023.

On August 22, 2023, the average daily sea surface temperature reached an all-time high of 66.18 degrees Fahrenheit (18.99 degrees Celsius). In 2023, about 94% of the ocean surface experienced at least one marine heatwave.

Over the past half-century, more than 90% of the surplus energy trapped in the Earth system by greenhouse gases and other substances has been stored in the oceans. Global ocean heat continues to increase, reaching an all-time high in 2023. Global mean sea level also reached a record high for the 12th consecutive year, about 101.4 millimeters above the 1993 level.

Sea ice in Antarctica hit record lows throughout 2023. Sea-ice area (cover) and sea ice extent recorded monthly average lows in eight months, and in 2023, 278 days hit a daily low. On February 21, 2023, both Antarctic sea-ice area and sea ice extent hit new record lows, surpassing the previous record lows recorded exactly one year earlier in February 2022.

Reference 
Blunden, J. and T. Boyer, Eds., 2024: “State of the Climate in 2023”. Bull. Amer. Meteor. Soc., 105 (8), 
Si–S483 https://doi.org/10.1175/2024BAMSStateoftheClimate.1

Contributor: IIYAMA Miyuki, Information Program