Hopes for keeping global warming below 1.5C above pre-industrial levels have all but disappeared after new data confirms that 2024 will be the first calendar year in which average temperatures exceeded that threshold.
Last year was the hottest year in human history, and the World Meteorological Organization (WMO) is expected to issue its latest stark warning later today that humans are pushing the Earth’s climate into uncharted territory.
Officials are also expected to confirm that this year’s average global temperature exceeded pre-industrial standards by 1.5 degrees Celsius for the first time, breaking the threshold set by the Paris Agreement.
The WMO assessment is calculated using global average temperatures across six datasets and uses the period 1850-1900 to provide a pre-industrial baseline. Temperature datasets collected by different agencies and agencies around the world vary slightly, mainly due to differences in how ocean temperatures are measured and analyzed over the decades. Some of these datasets fall just below the 1.5°C mark. new scientist I understand, but others are much better.
The Met Office predicts average temperatures in 2024 to be 1.53°C above pre-industrial levels, with a margin of error of 0.08°C. This is 0.07°C higher than the previous warmest year on record, in 2023. Meanwhile, according to the European Union’s climate change service Copernicus, temperatures in 2024 will be 1.6 degrees Celsius higher than before the industrial revolution and 0.12 degrees Celsius higher than the record set in 2023.
Scientists agree that the main causes of rising temperatures are continued human-induced climate change and El Niño patterns, which tend to push up global temperatures. But the scale and persistence of the heat has shocked many experts, who had predicted that temperatures would drop once El Niño ended in May 2024. Instead, Temperatures remained at record levels throughout the remainder of the year.
The world’s oceans are the most affected, with sea surface temperatures remaining at record levels through most of 2024, wreaking havoc on marine ecosystems. The year also saw no shortage of extreme weather events on the ground, including intense heatwaves, plummeting polar ice, deadly floods, and out-of-control wildfires. “This year was a year in which the effects of climate change were felt across the planet,” he says. david kingformer Chief Scientific Adviser to the UK Government and founder of the Climate Crisis Advisory Group.
Technically, the Paris Agreement goal of limiting global warming to below 1.5°C is calculated using a 20-year average, so even just one year above the threshold does not constitute a formal violation of the goal. It is not meant to be shown. But given the pace of warming in recent years, many scientists say the long-term Paris goal is no longer achievable.
At the press conference on January 9th, Samantha Burgess Professor Copernicus told reporters that it would probably be impossible to meet the goals of the Paris Agreement. “There is an extremely high possibility that the long-term average temperature will exceed 1.5 degrees Celsius and the upper limit of the Paris Agreement,” he said.
duochan from the University of Southampton in the UK is helping develop a new global dataset, DCENT, which he says uses cutting-edge technology to provide a more accurate historical picture of warming levels. It is said that a baseline is being generated. Although not included in WMO’s calculations, this new data set suggests global average temperatures in 2024 were 1.66°C above pre-industrial levels, he said.
As a result, Chan also believes that the 1.5°C target is probably no longer achievable. “We need to prepare for the broader future, and 1.5°C is not the only target we need to aim for,” he says. But he stressed that this is also an important time to be even more ambitious in reducing emissions. “It’s too early to give up,” he says.
The outlook for 2025 remains uncertain. There are early signs that global sea surface temperatures are finally starting to fall to expected levels. “This is a good sign that at least heat is dissipating from the ocean surface,” Burgess said. Meanwhile, after months of anticipation, La Niña phenomenon finally occurs near the Pacific equatorThis should reduce global temperatures until 2025.
But Chan cautions that if temperatures follow the pattern of past El Niño events, the world could have experienced a gradual change in warming. “Every time we have a major El Niño event… we are basically taking global warming to a new level,” he said, adding that 2024 could be the first time in years that average temperatures exceed 1.5 degrees Celsius. It suggests that there is.
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Source: www.newscientist.com