The American Meteorological Society’s 35th annual State of the Climate report has revealed that 2024 was a record setting year – with greenhouse gas concentrations, global temperature across land and sea, global sea level, ocean heat content and glacier ice loss all reaching record highs last year.
“The State of the Climate report is an annual scientific landmark. It is a truly global effort, in which hundreds of researchers from universities, government agencies and more come together to provide a careful, rigorously peer-reviewed report on our planet’s climate,” said American Meteorological Society president David J Stensrud.
“High-quality observations and findings from all over the world are incorporated, underscoring the vital importance of observations to monitor, and climate science to understand, our environment. The results affirm the reality of our changing climate, with 2024 global temperatures reaching record highs.”
Key findings from the report are:
– Earth’s greenhouse gas concentrations were the highest on record. Carbon dioxide (CO2), methane, and nitrous oxide — Earth’s major atmospheric greenhouse gases —reached record-high concentrations in 2024. The globally averaged CO2 level reached 422.8±0.1 parts per million, a 52% increase from the pre-industrial level of ~278ppm.
– Record temperatures were notable around the world. A range of scientific analyses indicate that the annual global surface temperature was 1.13°F to 1.30°F (0.63°C to 0.72°C) above the 1991–2020 average.
– Higher global temperatures impacted the water cycle. Water evaporation from land in the Northern Hemisphere reached one of the highest annual values on record and the global atmosphere contained the largest amount of water vapor on record, with over one-fifth of the globe recording their highest values in 2024.
– El Niño conditions contributed to record-high sea surface temperatures. Daily globally averaged sea surface temperatures were at record-high levels from the beginning of 2024 until late June. The mean annual global sea surface temperature in 2024 was a record high, surpassing the previous record of 2023 by 0.11°F (0.06°C).
– Ocean heat and global sea level were the highest on record. The global ocean heat content, measured from the ocean’s surface to a depth of 2,000m (approximately 6,561ft), continued to increase, and reached new record highs in 2024. Global mean sea level was a record high for the 13th consecutive year, reaching about 4.0 in (105.8 mm) above the average for 1993 when satellite altimetry measurements began.
The Arctic had its second-warmest year in the 125-year record. It was a record warm autumn (October to December) and an intense August heatwave in the summer brought all-time record-high temperatures to parts of the northwest North American Arctic, and record-high August monthly mean temperatures at Svalbard Airport reached more than 52°F (11°C).
Following record lows in 2023, net sea ice extent in Antarctica was larger than the previous year but continued to be well below average during much of 2024. The Antarctic daily minimum and maximum sea ice extents for the year were each the second lowest on record behind 2023, marking a continuation of low and record-low sea ice extent since 2016. And glaciers around the world were continuing to melt.
The international review is “the most comprehensive annual update on Earth’s climate”, according to AMetSoc. It is published by the Bulletin of the American Meteorological Society and this year was based on 589 contributions from 58 countries.
In related news, the Metop Second Generation A1 (Metop-SGA1) satellite, carrying the European Union’s Copernicus Sentinel-5 mission, was successfully launched from Europe’s Spaceport in Kourou, French Guiana, on August 13. Read the full story