The world has just experienced its hottest decade

(CNN) — A report considered the world’s most trusted source of climate updates has laid out the parlous state of a planet that has recorded its 10 hottest years over the last decade.

The World Meteorological Organization’s State of the Global Climate report lists alarming records that scientists say should shock the world into taking drastic action – but they warn they probably won’t, given the lack of urgency displayed by global leaders to date.

The report found the atmospheric concentration of carbon dioxide – as well as methane and nitrous oxide – are at the highest levels in the last 800,000 years.

Here are the report’s main findings:

2024 set a new heat record

Last year was confirmed to be the hottest since records began 175 years ago, beating the previous record set in 2023.

And 2024 was likely to be the first time global temperatures exceeded 1.5 degrees Celsius above the baseline set in 1850-1900, according to the WMO.

Scientists say that doesn’t mean that we’ve permanently crossed global limits set under the Paris Agreement – which the United States left on the first day of President Donald Trump’s second term – but we’re getting close.

Record levels of greenhouse gases were mostly to blame for higher temperatures, aided by a short-term boost from El Niño, a weather pattern that creates warmer water in the eastern Pacific, the report said.

Long-term global warming is estimated to be between 1.34 and 1.41 degrees Celsius up on the pre-industrial era, the WMO said.

United Nations Secretary-General António Guterres said limiting the global temperature rise to 1.5 degrees Celsius was still possible, but “leaders must step up to make it happen.”

Each of the past eight years set a record for ocean heat

Rising global temperatures inevitably mean warmer water, as oceans absorb 90% of the surplus heat.

New heat records have been set for each of the last eight years, and the rate of ocean warming over the past two decades is more than twice that recorded from 1950 to 2005.

Warm water has caused severe bleaching of coral reefs over the past year, fueled tropical and subtropical storms and exacerbated the loss of sea ice.

The rate of sea-level rise has doubled since satellite measurements began

The rate of global mean sea-level rise has doubled since the first satellite record in 1993, to reach a record high in 2024, the report said.

The rise of 2.1 millimeters per year recorded between 1993 and 2002 has been dwarfed by a 4.7-millimeter increase between 2015 and 2024.

Higher sea levels have knock-on effects for coastal communities, including flooding, erosion and the salinization of groundwater.

Sea-level rise is exacerbated by sea ice melt, and there’s no sign that’s slowing. The three years since 2021 brought the biggest three-year loss of Glacier mass on record.

“Exceptionally negative” losses were recorded in Norway, Sweden, Svalbard and the tropical Andes, the WMO said.

2024 saw the most people displaced due to climate impacts in 16 years

Tropical cyclones, floods, droughts, and other hazards in 2024 displaced the highest number of people since 2008, when 36 million people were forced from their homes.

That year, around half – 15 million – were displaced in China after the Sichuan earthquake. Flooding also affected millions in India.

In 2024, tropical cyclones and hurricanes brought destructive winds, severe rain and flooding. Dozens of unprecedent heatwaves were recorded including in Saudi Arabia where temperatures reached 50 degrees Celsius (122 degrees Fahrenheit) during the Hajj pilgrimage.

Wildfires and severe drought also raged through some countries, displacing people and disrupting food supplies. In eight countries, at least one million more people faced acute food insecurity compared with 2023, the WMO said.

Some of the turmoil could have been avoided with early-warning systems, though in parts of the world most vulnerable to climate impacts, there’s very little advance notice of disaster.

“Only half of all countries worldwide have adequate early-warning systems. This must change,” said Celeste Saulo, WMO secretary-general.

What scientists say

Sarah Perkins-Kirkpatrick, a professor at the Australian National University’s Fenner School of Environment and Society, said the world had reached a point where net zero emissions were no longer enough.

“We need to stop hitting snooze on our alarm, which is the now regularly occurring record-breaking global temperatures,” she said. “How much more do we need to scream and shout that climate change is happening, it’s because of us, and without any serious action, it’s only going to get worse? The longer this goes in, the harder it will be to make things better.”

Linden Ashcroft, a lecturer in climate science at The University of Melbourne, said not enough attention had been paid to warnings.

“Honestly, I’m not quite sure what to do next. Scream these findings from the tops of buildings? Write my comments in capitals? Saying all this while dancing on TikTok?” she said in a written statement.

“Unless we see real climate leadership from governments and businesses, I will save this response and send it through again next year.”

The-CNN-Wire
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