World breaks 1.5C warming limit for first time over a year long period

The 1.5C limit was a target of the Paris Agreement made in 2015, though continued emissions since then have made it increasingly difficult to achieve, Health and Science Correspondent Martin Stew reports

Global warming has exceeded 1.5C warming limit across an entire year for the first time, according to the European Union's climate service.

The global mean temperature for the past twelve months, between February 2023 and January 2024, was 1.52C above the 1850-1900 pre-industrial average.

The 1.5C limit was a key target of the Paris Agreement made in 2015, though continued emissions since then have made it increasingly difficult to achieve.

This temperature rise does not mean the agreement has failed - the limit will only be broken if it becomes the average for around 20 years, so any individual year above that would not mean a failure.

The current level of warming is estimated to be around 1.3C above pre-industrial levels, the Met Office said in January.

In 2024, the world experienced the warmest January on record. Credit: Copernicus

It comes as January 2024 was the warmest January on record globally.

The month saw an average ERA5 surface air temperature of 13.14C - 0.70C above the 1991-2020 average for January.

It was 0.12C above the temperature of the previous warmest first month of the year, in 2020.

The information was compiled by Copernicus, a component of the European Union’s space programme which monitors six key topics - atmosphere, marine, land, climate change, security and emergency.

European temperatures varied in January 2024 from much below the 1991-2020 average over the Nordic countries to much above average over the south of the continent.

Outside Europe, temperatures were well above average over eastern Canada, north-western Africa, the Middle East and central Asia, and below average over western Canada, the central USA and most of eastern Siberia.

Scientists have put the temperature rise over recent years down to El Niño - the world's biggest climate driver.

The El Niño Southern Oscillation (or ENSO) takes place in the southern tropical Pacific Ocean, and occurs every two to seven years.

El Niño is the name given to the warm phase of this natural cycle compared to its counterpart La Niña - the cool phase.

During El Niño events, the ocean heat is released into the atmosphere and redistributed around the globe. It is no coincidence the hottest years on record occur during El Niño years.

El Niño began to weaken in the equatorial Pacific, but marine air temperatures in general remained at an unusually high level, Copernicus said.

Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know...