Earth just had its hottest 12 months in the last 120,000 years

Earth’s last 12 months were the hottest life on the planet has lived through in the past 120,000 years, a new analysis has found. 

The report, produced by the U.S.-based Climate Central group, calculated that average global temperatures warmed to 1.32 degrees Celsius above pre-industrial levels, when humans started burning fossil fuels at scale.

“This is the hottest temperature that… humans have experienced for the time where we've decided to write down things and build cities and live together in large groups,” said Andrew Pershing, who led the analysis as Climate Central’s vice-president for science.

The study used peer-reviewed methodology the research group has automated to produce a global snapshot of how climate change is influencing daily temperatures. To achieve that, the scientists pulled data from their global Climate Shift Index (CSI), a tool that takes real temperatures to produce models under two scenarios — one that is actually measured and the other a counterfactual world where humanity never burned fossil fuels. 

Pershing said that the fact that we are setting a record this year is in some ways not surprising.

“We should expect a set of records because we live on a warming planet,” Pershing said.  

And while 2023 is consistent with that long-term warming trend, others have pointed to a number of swings — such as shipping regulations that reduce the emission of toxic sulphur — that could be pushing temperatures even higher. Then there’s El Niño, one half of a natural climate cycle in the South Pacific that tends to bring warmer temperatures to the Northern Hemisphere. 

“El Niño is really going to start to bite next year and so that's going to lead to even more warming as we move on into 2024,” Pershing said. 

Climate warming affected nearly everyone on the planet over the past 12 months

Over the last 12 months, 90 per cent of people on Earth experienced at least 10 days of temperatures very strongly affected by climate change — measured as three times more likely due to climate change. 

Another 73 per cent (5.8 billion people) experienced more than a month’s worth of these temperatures, according to the report. 

“We found that one in four people (1.9 billion) experienced a five-day heat wave (at minimum) that was strongly influenced by carbon pollution,” it states. 

The finger prints of carbon pollution spiked on every continent, especially in tropical areas in Africa, Central and South America, the Caribbean and Gulf of Mexico and in the Malay Archipelago. 

Long hot streaks stuck out in Mexico City, the southern U.S. and northern Mexico, in Indonesia, and in China. Developed countries at more northerly latitudes were also not spared, and in North America, B.C. emerged as a major hot spot for climate-driven warming. 

According to data shared by Climate Central, 94 per cent of residents in Canada’s westernmost province experienced more than 30 days of hot temperatures strongly influenced by climate change. That’s far greater than anywhere else in Canada save Yukon, where 90 per cent of the population lived through a similar climate-driven heat streak. 

12 months of extreme weather

Alongside the Climate Matters analysis, climate scientist Friederike Otto presented findings on 15 extreme weather events that tore across different parts of the world in the last 12 months. Those events were chosen for a closer look if they met one of several criteria, such as having affected more than a million people or led to the deaths of more than 100. 

“I was going to say the tip of the iceberg but it's really the opposite,” said Otto, a co-lead at World Weather Attribution, a research group that analyzes the presence or absence of a climate change fingerprint in extreme weather. 

In South America, drought driven by human-caused climate change led to a three per cent drop in gross domestic product. And in the Amazon, water levels dropped to their lowest level ever recorded, according to the report. 

It found that, in the U.S., 24 extreme weather events killed at least 383 people and led to financial losses greater than US$67 billion. The human toll also reached record levels — 93 people people died in a wildfire in Hawaii that is now considered the deadliest U.S. fire of the century. And in Canada, wildfires forced the evacuation of one in 200 people.

“Heat waves that approached the human survivability threshold stretched from East and South Asia to Europe and North Africa, killing at least 264 people in India and over 2,000 people in Spain, at a time when parts of the country also faced their driest period in 500 years,” the report noted. 

“In Italy, as temperatures surpassed 40 degrees Celsius in August and September, hospitals were unable to accommodate the number of people seeking care for heat-related illnesses, with COVID-era admission levels reported in emergency units.”

An extreme humid heat wave that hit Thailand and Laos in April “was basically impossible without climate change,” said Otto. 

'We have the know how'

Joyce Kimutai, principal meteorologist at the Kenya Meteorological Department, described how swings in drought and extreme rainfall were making it nearly impossible for residents in parts of her country to cope. But in other parts of Africa, a paucity of public and meteorological records make climate attribution difficult.  

At a press conference Wednesday, one reporter asked what historians would say about 2023 when they looked back 50 years from now. 

“We know for certain that they will look back and say, 'Wow, those people had it really easy,'” said Pershing. “This is as easy as it gets, right? It's only gonna get harder from here.”

Otto pushed back against comments made by some high-profile scientists who suggested keeping global temperatures below 1.5 C of warming — a global target — is now out of reach. 

“I think that's a very stupid thing to say,” she said. “We know what we need to do to stop burning fossil fuels. We have the technologies. We have the know how... But at the moment, we don't do it.”

“There’s duty of care here,” added Kimutai. “And not just for us, but for generations to come.”