State of the Global Climate 2023 Report

World Meteorological Organization, 20 March 2024

This latest WMO report confirms 2023 was officially the hottest year in recorded history, shattering records of Antarctic sea ice decline, glacier retreat, ocean heat and acidification, sea-level rise, and greenhouse gas levels. Global average near-surface temperature reached 1.45°C above the pre-industrial baseline, increasing today’s ten-year average to 1.20°C. WMO noted with alarm how heatwaves, floods, droughts, wildfires and rapidly intensifying tropical cyclones upended every-day life for millions and inflected many billions of dollars in economic losses over the past year.

The report highlighted many notable cryosphere losses. Soaring temperatures in western North America and Europe produced the largest global glacier ice loss on record since 1950, with some regions and countries (such as Switzerland) loosing 10% of their ice volume over the past two to three years. Greenland experienced its warmest summer on record in 2023; and at the southern pole, Antarctic sea ice extent was by far the lowest ever measured, with the maximum extent at the end of winter dropping 1 million km2 below the previous record year. On an average day in 2023, nearly one third of the global ocean was gripped by a marine heatwave, harming vital ecosystems and food sources. By the end of 2023, over 90% of the ocean had experienced heatwave conditions at some point during the year.

One of the key conclusions: the cost of climate inaction is higher than the cost of acting in time to limit warming close to 1.5°C. In an average 1.5°C scenario, annual climate finance investments need to reach almost USD 9 trillion by 2030, and a further USD 10 trillion through to 2050. Yet the cost of inaction is much higher. Authors calculate that the cost difference between projected economic losses under a business-as-usual scenario, and those incurred with 1.5°C is at least USD 1,266 trillion through 2100. This figure is, however, likely to be an underestimate. As the world approaches the lower 1.5°C limit of the Paris Agreement, the need for urgent climate action becomes strikingly clear.

Full report: https://library.wmo.int/records/item/68835-state-of-the-global-climate-2023
Plain-language briefing: https://wmo.int/news/media-centre/climate-change-indicators-reached-record-levels-2023-wmo