Long-term warming currently at 1.3°C above pre-industrial level: WMO

The Jan–Sept 2024 global mean surface air temperature was 1.54°C above the pre-industrial average, boosted by a warming El Niño event, according to an analysis

Long term warming is currently likely to be about 1.3°C above pre-industrial levels, the World Meteorological Organisation (WMO) said on Monday.

WMO has established an international team of experts to track the long-term changes in average temperature. (Representative file photo)

For 16 consecutive months (June 2023 to September 2024), the global mean temperature likely exceeded anything recorded before, by a wide margin, the World Meteorological Organisation’s consolidated analysis of the datasets said on Monday.

The January – September 2024 global mean surface air temperature was 1.54°C above the pre-industrial average, boosted by a warming El Niño event, according to an analysis of six international datasets used by WMO. But the long-term warming measured over decades remains below 1.5°C, it clarified.

WMO has established an international team of experts to track the long-term changes in average temperature, and the initial indication is that long-term global warming is currently likely to be about 1.3°C compared to the 1850-1900 baseline, State of Climate 2024 Update of WMO said.

“One or more individual years exceeding 1.5°C does not necessarily mean that “pursuing efforts to limit the temperature increase to 1.5°C above pre-industrial levels” as stated in the Paris Agreement is out of reach. 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 said.

This year will see the increase in the world’s average annual temperature breaching the Paris Agreement’s threshold of 1.5°C, the Copernicus Climate Change Service (C3S) indicated last week.

C3S said it is virtually certain that the annual temperature for 2024 from ERA5 (hourly temperature data from 1950 onwards) will be more than 1.5°C above the pre-industrial level, and likely that it will be more than 1.55°C above.

The report also said that 2015-2024 period will be the warmest ten years on record; the loss of ice from glaciers, sea-level rise and ocean heating are accelerating; and extreme weather is wreaking havoc on communities and economies across the world, WMO added.

Ocean heat content in 2023 was the highest on record. Ocean warming rates show a particularly strong increase in the past two decades. Sea level rise is accelerating because of thermal expansion of warmer waters and melting glaciers and ice sheets. From 2014-2023, global mean sea level rose at a rate of 4.77 mm per year, more than double the rate between 1993 and 2002.

“The El Niño effect meant it grew even more rapidly in 2023. Preliminary 2024 data show that, with the decline of El Niño, it has fallen back to levels consistent with the rising trend from 2014 to 2022,” the report said.

In 2023, glaciers lost a record 1.2-meter water equivalent of ice – about five times the amount of water in the Dead Sea. It was the largest loss since measurements began in 1953 and was due to extreme melting in North America and Europe.