Climate change indicators reached record levels in 2023: WMO

A new report from the World Meteorological Organization (WMO) shows that records were once again broken, and in some cases smashed, for greenhouse gas levels, surface temperatures, ocean heat and acidification, sea level rise, Antarctic sea ice cover and glacier retreat.

Heatwaves, floods, droughts, wildfires and rapidly intensifying tropical cyclones caused misery and mayhem, upending every-day life for millions and inflicting many billions of dollars in economic losses, according to the WMO State of the Global Climate 2023 report.

The WMO report confirmed that 2023 was the warmest year on record, with the global average near-surface temperature at 1.45 °Celsius (with a margin of uncertainty of ± 0.12 °C) above the pre-industrial baseline. It was the warmest ten-year period on record.

“Sirens are blaring across all major indicators… Some records aren’t just chart-topping, they’re chart-busting. And changes are speeding-up.” said United Nations Secretary-General António Guterres.

“Never have we been so close – albeit on a temporary basis at the moment – to the 1.5° C lower limit of the Paris Agreement on climate change.” said WMO Secretary-General Celeste Saulo. “The WMO community is sounding the Red Alert to the world.”

“Climate change is about much more than temperatures. What we witnessed in 2023, especially with the unprecedented ocean warmth, glacier retreat and Antarctic sea ice loss, is cause for particular concern,” she said.

On an average day in 2023, nearly one third of the global ocean was gripped by a marine heatwave, harming vital ecosystems and food systems. Towards the end of 2023, over 90% of the ocean had experienced heatwave conditions at some point during the year.

The global set of reference glaciers suffered the largest loss of ice on record (since 1950), driven by extreme melt in both western North America and Europe, according to preliminary data.

Antarctic sea ice extent was by far the lowest on record, with the maximum extent at the end of winter at 1 million km2 below the previous record year – equivalent to the size of France and Germany combined.

“The climate crisis is THE defining challenge that humanity faces and is closely intertwined with the inequality crisis – as witnessed by growing food insecurity and population displacement, and biodiversity loss” said Celeste Saulo.

Comparison of global mean temperature difference data sets from the 1850s to 2023 relative to the 1850-1900 average.

Annual global mean temperature anomalies (relative to 1850–1900) from 1850 to 2023. Data are from six data sets

The number of people who are acutely food insecure worldwide has more than doubled, from 149 million people before the COVID-19 pandemic to 333 million people in 2023 (in 78 monitored countries by the World Food Programme). Weather and climate extremes may not be the root cause, but they are aggravating factors, according to the report.

Weather hazards continued to trigger displacement in 2023, showing how climate shocks undermine resilience and create new protection risks among the most vulnerable populations.

There is, however, a glimmer of hope.

Renewable energy generation, primarily driven by the dynamic forces of solar radiation, wind and the water cycle, has surged to the forefront of climate action for its potential to achieve decarbonization targets. In 2023, renewable capacity additions increased by almost 50% from 2022, for a total of 510 gigawatts (GW) – the highest rate observed in the past two decades.

This week, at the Copenhagen Climate Ministerial on 21-22 March, climate leaders and ministers from around the world will gather for the first time since COP28 in Dubai to push for accelerated climate action. Enhancing countries Nationally Determined Contributions (NDCs) ahead of the February 2025 deadline, will be high on the agenda, as will delivering an ambitious agreement on financing at COP29 to turn national plans into action.

“Climate Action is currently being hampered by a lack of capacity to deliver and use climate services to inform national mitigation and adaptation plans, especially in developing countries. We need to increase support for National Meteorological and Hydrological Services to be able to provide information services to ensure the next generation of Nationally Determined Contributions are based on science”, said Celeste Saulo.

The State of the Global Climate report was released in time for World Meteorological Day on 23 March. It also sets the scene for a new climate action campaign by the UN Development Programme and WMO to be launched on 21 March (today). It will inform discussions at a climate ministerial meeting in Copenhagen on 21-22 March.

Dozens of experts and partners contribute to the report, including UN organizations, National Meteorological and Hydrological Services (NMHSs) and Global Data and Analysis Centers, as well as Regional Climate Centres, the World Climate Research Programme (WCRP), the Global Atmosphere Watch (GAW), the Global Cryosphere Watch and Copernicus Climate Change Service operated by ECMWF.