WMO issues “red alert” over global warming, says 2015-24 hottest ten years on record 

The State of the Climate, 2024, report released today by the World Meteorological Organization (WMO) notes that the 2015-24 period has been the “warmest ten years on record”. 

Releasing the report on the sidelines of the COP29 climate conference currently underway at Baku, Azerbaijan, the Prof Celeste Saulo, Secretary General, WMO, said that extreme weather is “wreaking havoc” on communities and economies across the world.

The report is a “red alert” over the ever-increasing greenhouse gas levels in the atmosphere, she said. 

WMO is a specialized agency of the United Nations responsible for promoting international cooperation in atmospheric science and meteorology. It monitors weather, climate, and water resources for countries to forecast and disaster mitigation. 

The report, which is an analysis of six international datasets, says that the January – September 2024 global mean surface air temperature was 1.54 °C above the pre-industrial (1850-1900) average. WMO points out that while this is higher than the target of 1.5 degrees C for global warming, it does not mean that the target is lost. One or more individual years exceeding 1.5°C does not necessarily mean that the Paris Agreement target is out of reach, it says.

“The exceedance of warming levels referred to in the Paris Agreement should be understood as an exceedance over an extended period, typically decades or longer, although the Agreement itself does not provide a specific definition,” WMO says. 

Nevertheless, the report paints a grim picture of global climate. WMO has used three different approaches for measuring global warming. “All three of these approaches indicate that global warming up to 2023 is at about 1.3°C compared to the 1850-1900 baseline,” it said, stressing that “whether it is at a level below or above 1.5°C of warming, every additional increment of global warming leads to changes in extremes and risks becoming rapidly larger.” 

GHG emissions  

The WMO report notes that the atmospheric concentration of carbon dioxide has increased from around 278 ppm in 1750 to the current level of 420 ppm, an increase of 51 per cent. The average CO growth rate during the past decade was 2.4 ppm per year. Emissions from fossil fuels have been the largest source of human emissions since the 1950s. Global averaged methane concentrations increased from 729 ppb during preindustrial time to 1934 ppb in 2023, which represents an increase of 165 per cent. Nitrous oxide (N O) concentration increased from 270 ppb in 1750 to 336.9 ppb in 2023, which represents a 24 per cent increase. 

This rate corresponds to an average absorption of approximately 3.1 million terawatt-hours (TWh) of heat each year from 2005-2023, more than 18 times the world’s energy consumption in 2023.