While Britain might now be facing freezing weather, scientists have confirmed that 2024 was globally the hottest year on record.
A report published by the Copernicus Climate Change Service (C3S), reveals that temperatures were 0.12°C (0.22°F) above 2023, the previous warmest year on record.
That makes 2024 the first calendar year on record to exceed 1.5°C above the pre-industrial level.
Although this single year does not mean the targets of the Paris Agreement have already been missed, experts say that humanity is now ‘dangerously close’ to this milestone.
The data shows that an exceptionally hot start to the year brought the average global air temperature in 2024 to 15.1°C (59.2°F).
While temporary patterns like El Niño helped push temperatures into the extremes, scientists say human-caused climate change remains the ‘primary driver’ of extreme temperatures.
And with the rate of carbon dioxide entering the atmosphere even higher than in previous years, the planet’s warming shows no signs of slowing any time soon.
Dr Friederike Otto, a climate policy expert from Imperial College London, says: ‘This record needs to be a reality check. The climate is heating to levels we’ve spent years trying to avoid because countries are still burning huge amounts of oil, gas and coal.’
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The C3S analysis combines billions of measurements taken from ships, aircraft, satellites, and weather stations around the world.
This gives scientists the most accurate measure of the average temperatures around the world.
Although this data now confirms that 2024 was the hottest year in recorded history, scientists have known that this was likely since early summer.
Each month from January to June last year was warmer than any corresponding month in previous years – concluding a 13-month run of record-breaking months.
This meant that average global temperatures were already so high that it was almost certain 2024 would be hotter than any other year.
However, 2024’s status was secured after every month from July to December was the second hottest after 2023 – except August, which was tied for the second warmest.
Surface temperatures were their hottest on record for every populated continent, with the exception of Oceania which experienced its third warmest year.
On average, 2024 was 0.72°C (1.3°F) warmer than the 1991-2000 average and a sweltering 1.6°C (2.88°F) hotter than the average for the pre-industrial period between 1850 and 1900.
The average global temperature reached 15.1°C (59.2°F), 0.72°C (1.3°F) warmer than the 1991-2000 average
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This comes as bad news for the aims of the Paris Agreement, an international treaty signed in 2016 with the aim of keeping global warming below 1.5°C warmer than the pre-industrial average.
Out of the last 12 months, the global average temperature exceeded 1.5°C in 11.
Going back further, all months since July 2023, except for July 2024, have exceeded the 1.5°C level.
Worryingly, this puts the average temperature of the last two years above 1.5°C of warming.
These extreme temperature increases will still be alarming to many after a year of extreme weather made worse by climate change.
Dr Otto says: ‘A year of extreme weather showed just how dangerous life is at 1.5°C.
‘The Valencia floods, US hurricanes, Philippines typhoons and Amazon drought are just four disasters last year that were worsened by climate change. There are many, many more.’
As the global surface temperature increases, the warmer air is capable of storing more water vapour and more energy.
Every populated continent experienced its hottest year on record. The only exception was Oceania (Australasia) which had its third-warmest year
The increased temperature led to record-breaking amounts of water vapour in the atmosphere which created more severe storms and flooding around the world
In October last year, flash flooding led to hundreds of deaths and damage to thousands of homes in Valencia, Spain. Experts believe the flooding was made more severe by climate change
This leads to an increase in the severity of events like flash floods and the destructive potential of tropical storms and typhoons.
According to the C3S report, the total amount of water vapour in the atmosphere reached a record high, about five per cent higher than the 1991-2000 average.
Combined with high sea surface temperatures, C3S says this contributed to the development of major storms and tropical cyclones.
Rising temperatures also make devastating wildfires more likely as some regions go long periods without rainfall.
The LA wildfires, which are still raging at the time of writing, were made possible by the county’s driest start to the year on record.
The Los Angeles Airport recorded just 0.08 centimetres of rain since October 1, creating ‘severe drought’ conditions across Los Angeles County.
However, the Paris Agreement has not yet been broken since this refers to temperatures across a much larger 20-year average.
Professor Joeri Rogelj, a climate change expert at Imperial College London, says: ‘A single year with temperatures 1.5°C above pre-industrial levels does not mean we’ve reached 1.5°C of global warming. However, it does mean we’re getting dangerously close.’
Increased surface temperatures also lead to a greater number of wildfires. Currently, fires in Los Angeles (pictured) have displaced over 130,000 people after severe droughts triggered blazes around the city
Although this year exceeded 1.5°C above pre-industrial levels, the target of the Paris Agreement has not yet been missed since longer-term averages remain below this level. This graph shows the five-year average for global surface temperatures
‘The Paris Agreement sets limits to global warming not out of convenience but out of the necessity to limit harm to and suffering of people.
‘Every fraction of a degree—whether 1.4, 1.5, or 1.6°C—brings more harm to people and ecosystems, underscoring the continued need for ambitious emissions cuts.’
Part of the reason that 2023 and 2024 were exceptionally warm is a natural cyclical phenomenon called the El Niño Southern Oscillation.
During an El Niño year, the average surface sea temperatures in the central and eastern Pacific rise significantly above average.
This disrupts the regular flow of currents, sending warmer waters eastwards and pushing up global air temperatures.
Over the last two years, this has led to average temperatures exceeding their normal ranges all around the world.
The C3S’s report shows that global sea temperatures are now beginning to fall, indicating a return to more neutral conditions in the Pacific and an end to the El Niño period.
Dr Paulo Ceppi, senior lecturer in climate science at Imperial College London, says: ‘It’s unlikely 2025 will be as hot as 2024, but people shouldn’t think that’s climate change hitting pause or plateauing.
During 2023 and 2024 a natural weather phenomenon called the El Niño Southern Oscillation created exceptionally high sea surface temperatures. This event occurs once every 14 years, leading to warmer temperatures. However, the end of El Niño does not mean that temperatures will begin to decline
‘There are ups and downs in global temperatures due to natural processes, like El Niño, and a small dip doesn’t change the clear upward trajectory we’re on.’
Human-caused climate change triggered by greenhouse gases is still the primary reason that global temperatures are increasing year-on-year.
In fact, even though El Niño is over, some drivers of climate change are only set to accelerate.
The C3S report shows that sea ice extents were significantly below average in the Arctic and Antarctic.
Antarctic sea ice extent reached record or near-record low values for the second year in a row, falling to its lowest monthly extent for November and second lowest from June to October.
Dr Ceppi says: ‘The recent heat was exacerbated by a decrease in the amount of cloud and sea ice, causing Earth to absorb more sunlight. This confirms climate model predictions of melting sea ice and shrinking cloud cover as the world warms.’
Likewise, the amount of greenhouse gases (GHG) in the atmosphere continued to rise to record levels last year.
In 2024, carbon dioxide concentrations were 2.9 parts per million higher than in 2023 and methane concentrations were 3 parts per million higher.
In 2024, the concentration of greenhouse gases in the atmosphere reached record highs. Scientists agree that this is one of the primary drivers of warming temperatures
Antarctic sea ice also hit near-record lows during 2024. Reduced sea ice means that less energy from the sun is reflected back out of the atmosphere, triggering even faster rates of warming
The rate at which CO2 is being added to the atmosphere was actually faster in 2024 than in recent years due to the continued use of polluting fossil fuels like coal. Pictured: The Jaenschwalde coal-fired power plant operates in Jaenschwalde, Germany during October last year
While the rate at which methane was being added was slower than in previous years, the increase in carbon dioxide concentration has actually accelerated.
Laurence Rouil, co-director of the Copernicus Atmosphere Monitoring Service, says: ‘Our data points clearly to a steady global increase of greenhouse gas emissions and these remain the main agent of climate change.’
If GHG emissions do not decrease rapidly, the UN has warned that the world is on track for a ‘catastrophic’ 3.1°C of global warming by the end of this century.
That could lead to devastating consequences including a massive expansion of arid regions, the collapse of global ocean currents, and rising sea levels around the world.
Carlo Buontempo, co-director of the Copernicus Atmospheric Monitoring Service, concludes: ‘Humanity is in charge of its own destiny but how we respond to the climate challenge should be based on evidence.
‘The future is in our hands – swift and decisive action can still alter the trajectory of our future climate.’
