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July likely Earth's hottest month in 120,000 years, analysis says

July shatters Earth's previous record for the hottest month in recorded history, according to a recent analysis.
old-man-lake-wildfire
The Old Man Lake wildfire burns roughly 18 kilometres east of Houston, B.C., July 20, 2023. It is one of more than 4,700 wildfires that have so far burned across Canada this season — many spurred on by sustained hot and dry temperatures.

Global temperatures peaked to their highest levels ever recorded this month, with July possibly ranking as the hottest 30-day period in the past 120,000 years, according to a new analysis.

The spike in average global temperatures now sits 1.5 degrees Celsius hotter than the planet was before humanity ramped up its burning of fossil fuels during the Industrial Revolution, according to Karsten Haustein, a climate scientist at Leipzig University in Germany. That’s 0.2 C hotter than the previous record set in July 2019.

“Not only will it be the warmest July, but the warmest month ever in terms of absolute global mean temperature,” Haustein said. “We may have to go back thousands if not tens of thousands of years to find similarly warm conditions on our planet.”

Scientists suspect pre-industrial global average temperatures hovered around 15.5 C. But there have never been thermometers in every place around the planet at any time (fewer then), and that number could be slightly off.

For that reason, climate scientists take the ramp-up of fossil fuel burning as a zero-point. From that baseline, annual and monthly deviations show scientists how humanity it changing global temperatures over time.

Haustein says most scientists wait until the month is over, but this July was so hot that even a massive turn in global weather over the coming days would not change the outcome, Haustein.

“It’s never been as easy to predict the warmest month as now,” he said.

Planet Earth faces ‘fever’ temperatures

A warming of 1.5 C above pre-industrial levels is the warming threshold countries around the world agreed to avoid through the 2015 Paris Agreement. But breaking that ceiling this month does not mean the goal is out of reach.

Global average temperatures spiked to 1.5 C in 2016 and 2020, though this is the first time it has happened during the Northern Hemisphere’s summer when the planet is at its hottest.

Friederike Otto, a climate rapid attribution researcher at London’s Imperial College, said the record hot July has directly manifested in more extreme weather events.

“Global mean temperature doesn’t kill anyone. But of course, global mean temperature is the fever temperature we measure from our planet,” Otto said.

July saw daily extreme temperature records tumble across the globe, with at least 15 countries setting all-time highs. On July 12, California’s Death Valley saw the hottest midnight ever recorded on Earth when temperatures hovered just shy of 49 C. China hit its hottest temperature this month at more than 52 C, while the Italian capital of Rome nearly 42 C temperatures this month shattered a heat record it had set only a year earlier.

At the same time, flooding has swept into many communities. At least 13 people are reported to have died when a tunnel flooded in South Korea; eight children were killed at a cricket match during record monsoon rains in Pakistan; and four bodies — including two children — have been recovered since torrential rains flooded areas of Nova Scotia.

Lancet Countdown executive director Marina Romanello pointed to the group’s latest study, which tracks how climate change is impacting human health across 86 countries. The 2022 study, which involved dozens of authors from more than 50 research institutions, offered a rough global estimate showing that people 65 and older have seen a 68 per cent increase in heat-related mortality since the early 2000s.

“Beyond those direct impacts, it's very important to keep in mind that extreme heat exposure is also starting to undermine our health through more indirect pathways.” said Romanello, pointing to everything from the availability of food to people taking time off work.

By 2020, the occurrence of heat waves was associated with almost 100 million more people reporting moderate to severe food insecurity compared to the years 1981 to 2010. By 2021, global extreme heat led to an estimated loss in potential income of almost US$700 billion, representing a 37 per cent increase in potential labour hours lost since the 1990s.

"The much used term ‘unprecedented’ no longer describes the horrific temperatures we are experiencing,” said former United Nations climate chief Christiana Figueres.

EL Niño collides with climate change

The new global temperature record comes as the warming influence from a growing El Niño — a natural climate cycle in the South Pacific that drives warmer temperatures in the Northern Hemisphere — collides with the steady march of human-caused climate change, according to the World Meteorological Association (WMO).

“It’s like we’ve had the global air conditioner on for three years,” Bill Merryfield, a research scientist who works with Environment and Climate Change Canada, said of La Niña's outgoing cooling effects.

Only in the the last three months have signs emerged that El Niño conditions are taking over. Merryfield said it’s not clear why such warm temperatures are occurring so soon. That’s because the strongest effects of the natural oscillation aren’t expected to be peak until late 2023. It’s usually the following year when its influence starts to raise global temperatures, he said.

“It is a little bit surprising that so soon after the current El Niño started that we’re seeing such a fast global rise in temperature,” Merryfield said.

Some have hypothesized it’s due to a lack of airborne particles reflecting solar energy back into space, either from less Sahara dust blowing into the Atlantic or the result of a global ban on dirty shipping fuels that recently took effect, added the Canadian researcher.

“It may be a perfect storm, but I don’t think too many people saw it coming so soon,” said Merryfield, whose models helped feed the WMO recent climate forecasts.

Beyond the scale of a month, the WMO calculates there is a 98 per cent chance the next five years will surpass 2016 as the hottest year ever recorded, and a 66 per cent chance annual average temperatures will exceed 1.5 degrees Celsius of warming above pre-industrial levels.

Without action to reign in the burning of fossil fuels soon, the long-term outlook is even bleaker. Based on current national policies to reign in climate change, global average temperatures will rise to 2.8 C above pre-industrial levels by the end of the century, according to the United Nations.

At that level of warming, flood damage is expected to more than double compared to a world where global warming is halted at 1.5 C degrees above pre-industrial levels. Up to nearly a third of terrestrial species will likely face a very high risk of extinction at that point. And access and production of food will fall with weakening of soil health, lack of freshwater and increase in pressure from pests and disease.

That future is not inevitable, though the window to avoid it is increasingly closing, say experts. The U.N.’s Intergovernmental Panel on Climate Change (IPCC) says planetary emissions need to peak before 2025 and drop more than 40 per cent by 2030 if the world has a hope of remaining below the 1.5 C warming threshold.

‘We know who is responsible’

In recent years, climate models have led the international body to declare the risk of a “wildfire crisis,” among threats from extreme weather, rising sea levels and a growing extinction crisis.

Canada is warming two to four times faster than the rest of the world. This year, all-time temperature records have fallen across the country’s north.

In Western Canada, a spring heat wave primed forests for burning, and across the country, a record wildfire season has led to the scorching of land nearly the size of North Korea. The grim tally is expected to grow. By Thursday morning, more than 1,000 wildfires burned across Canada — including more than 220 “out of control” wildfires in British Columbia, where the burning season tends to last well into the fall.

“We know who is responsible for the majority of these impacts. We are past the place where we can no longer attribute these impacts directly to particular actors,” said Catherine Abreu, the executive director of Destination Zero, a Canadian organization working to transition away from fossil fuels.

Abreu pointed to recent research published in the Journal of Environmental Research Letters showing nearly 40 per cent of the land burned in B.C. and the American West is linked to the fossil fuel emissions of the world’s worst 88 emitters.

“We can name those culprits and those are the same 88 companies that are responsible for close to 70 per cent of global greenhouse gas emissions since 1988,” Abreu said. “They are largely fossil fuel companies and some cement manufacturers.”

Heat ripples into extreme weather

Record heat waves across Europe have been matched with devastating floods ripping through Italy and the U.S. northeast. And on July 24, an estimated three months of rain fell on Nova Scotia, triggering the worst floods Atlantic Canada has seen in half a century.

The heat has not been limited to land. Extraordinarily high temperatures have been recorded in the waters off Newfoundland this week, with thousands of square kilometres of ocean experiencing sea surface temperatures 5 C above normal, and in some areas, double that.

“When I saw that, I thought it was quite extraordinary,” Merryfield said. “It is a bit shocking to see temperatures that warm off the coast of Canada.”

The rise of rapid attribution science has made humanity’s footprint on extreme weather clearer. An international body of leading climate scientists known as World Weather Attribution recently found heat waves currently hitting the U.S., Mexico and Europe would have been “virtually impossible” without the influence of climate change.

Others researchers in Canada have found preliminary evidence the spring heat wave that rocked Alberta and B.C. was made up to 10 times worse due to human influence on the world’s climate system.

And in April, Otto was part of another rapid attribution study that found extreme heat in Spain and North Africa would have been “almost impossible” without the influence of climate change.

“Without human-induced climate change, these heat waves would have been so rare that it would be the statistical equivalent of impossible,” Otto said.

“As long as we continue to be burning fossil fuels, these records will continue to be broken.”