By the end of the weekend, the four hottest days scientists have ever recorded, dozens of people had died in severe flooding and massive landslides caused by Tropical Storm Gaemi, which reduced half of Jasper Island to ash, and about 3.6 billion people on Earth had endured temperatures that would be extremely rare in a world without the burning of fossil fuels and other human activity, according to an analysis by Climate Central scientists.
This extraordinary warming represents the culmination of an unprecedented period of global warming that has astonished even researchers who have dedicated their lives to studying climate change.
Since last July, the planet’s average temperature has been consistently 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial levels, a threshold that scientists say must not be crossed in the short term if the world wants to avoid the worst effects of global warming.
Johan Rockström, director of Germany’s Potsdam Institute for Climate Impact Research, said “experience” a 1.5°C world shows that rising temperatures could cause the natural systems on which humanity depends to collapse. Forests are less able to absorb carbon from the atmosphere. Sea ice around Antarctica is close to record lows. Coral bleaching has become so extreme that it has forced scientists to change their metrics.
Scientists predict the current record-breaking heatwave will end, but warn it may be hard for some parts of the planet to recover from last year’s heat.
“The extreme events we’re experiencing right now show that these systems are becoming less resilient,” Rockström said. “We can’t risk letting this go any further.”
This week’s record-breaking temperatures come on the heels of 13 consecutive months of unprecedented temperatures, caused in part by the Earth’s shift toward an El Niño weather pattern that’s warming the oceans, and pollution from the burning of coal, oil and gas.
The warming neared a crest on Sunday, as data from Europe’s climate monitor, the Copernicus Climate Change Service, showed that the global average temperature rose slightly above the record set just over a year ago.
However, this new standard only lasted for 24 hours, as the highest temperature ever recorded was 17.16 °C (62.89 °F) on Monday. Tuesday was the second-hottest on record, and Wednesday was tied with Sunday for third-hottest.
These figures may not seem extreme, but they are the average of thousands of data points collected from the Arctic to the Antarctic, in places that experience winter as well as midsummer. The preliminary data was generated using advanced analysis that combines global weather observations with cutting-edge climate models. Independent researchers say the Copernicus method is highly reliable.
The world’s oceans are also experiencing record heat. Copernicus data shows that ocean temperatures around Taiwan are 2-3°C (3.6-5.4°C) warmer than normal, contributing to Typhoon Gaemi’s devastating effects. Research shows that warmer oceans lead to stronger tropical cyclones, and a warmer atmosphere can hold more water, leading to more rainfall.
Meanwhile, about 2,000 weather stations around the world set new records for daily maximum temperatures over the past seven days, according to the National Centers for Environmental Information.
Scientists have yet to quantify the role of global warming in all of this year’s extreme weather, but there is ample evidence that climate change is making heat waves, storms and fires more frequent and intense.
“We are running out of metaphors to describe the relentless pace and scale at which the world is currently breaking new records,” said Carlo Buontempo, director of the Copernicus Institute.
Sometimes, he says, it feels like the Earth’s temperature is rising inevitably, like a helium balloon, and all he can do is stand below and say, “Look, it’s getting hotter.”
Scientists estimate the Earth’s average temperature based on observations going back to 1850, and currently measure it from data from more than 20,000 land-based stations, as well as readings from ships and buoys around the world.
To convey the severity of Earth’s current heat, other researchers have looked to the planet’s past. Paleoclimatologists have studied tree rings, lake sediments, and other records of ancient climate, and concluded that Earth is likely currently warmer than it has been in more than 100,000 years, before the start of the last ice age.
Humanity is currently facing a situation that it has never experienced before. In the five-day period ending Friday, nearly half of the world recorded at least one day of “exceptionally hot” temperatures — temperatures that would be rare or impossible in a world without climate change, according to a Climate Central analysis.
U.N. Secretary-General Antonio Guterres on Thursday called for improved warning systems, stronger worker protections and other policies to protect people from the scorching heat.
“Extreme temperatures are no longer just a one-day, one-week or one-month phenomenon,” he told a news conference.
Buontempo predicts that Earth’s record-breaking streak may soon come to an end. The National Oceanic and Atmospheric Administration declared the official end of El Niño last month, reflecting a cooling in the tropical Pacific Ocean. The end of summer in the Northern Hemisphere, where most of the world’s land mass is located, also tends to lower global temperatures.
But the amount of warming-trapping carbon in Earth’s atmosphere is unprecedented, reaching its highest level in more than three million years, and the world would remain dangerously warm even without El Niño. Many researchers predict that 2024 will surpass the benchmark set in 2023 and become the hottest year on record.
“The fluctuations we’re seeing are relatively modest compared to the very large, multi-decade warming trends,” said climate scientist Kim Cobb, director of Brown University’s Institute for Environmental and Social Studies. “We’re dancing around a climate average that’s very dangerous for communities and ecosystems around the world.”
This week’s heatwave has been concentrated in Antarctica, where temperatures have been up to 12 degrees Celsius (21.6 degrees Fahrenheit) above normal.
Lynn Tully, a research scientist at the Scripps Institution of Oceanography at the University of California, San Diego, said the unusual phenomenon was likely caused by strong winds pushing warm air over the continent, conditions that make it difficult for the ocean to freeze over during the peak of sea ice formation.
“It looks like global warming is finally reaching Antarctica, and that’s pretty scary,” she said.
Sea ice around Antarctica is at its second-lowest level on record for this time of year, behind only July of last year, and Tully said the region has not been able to recover after losing unprecedented amounts of ice during the 2023 melt season.
To Rockström, the loss of Antarctic sea ice is a sign that recent global warming may be weakening Earth’s ability to buffer against the worst effects of climate change. Sea ice helps keep the poles cool by reflecting much of the sunlight that hits them back into space. When the ice melts and sunlight reaches the dark open ocean, that energy is absorbed by the Earth.
He also pointed to a new analysis that found that dying and burning forests in the Amazon, Asia, and Canada are losing a lot of their capacity to absorb excess carbon dioxide produced by human activities. The study, which has not yet been published in a peer-reviewed journal, focuses on data from 2023, and scientists aren’t yet sure whether the findings are a short-term blip or a more permanent change.
This year, the world’s forests are struggling again. As of Wednesday, Canadian authorities were battling 310 out-of-control wildfires, including one that ravaged the town of Jasper. Trees burned by weeks of intense heat are providing fuel for fast-spreading fires in Northern California. The Amazon is bracing for a second consecutive year of extreme drought that studies show is caused by climate change.
Robert Rohde, chief scientist at Berkeley Earth, a climate-data nonprofit, said these extreme events are “indicative” of what might happen to the planet if global temperatures consistently exceed 1.5 degrees Celsius, which researchers predict will happen in the early 2030s.
Research suggests that exceeding that threshold could trigger irreversible changes to major Earth systems, including the collapse of the Greenland ice sheet, the complete loss of tropical coral reefs and the rapid thawing of some permafrost.
Rockström said what the world is seeing now is “an alarming sign that a tipping point may be approaching.”
Cobb said that as long as humans continue to emit carbon into the atmosphere, disasters will continue to happen and records will continue to be broken.
“This is Russian roulette with climate disruption,” she said. “Your community will be hit by a hurricane. Your city will be hit by a heat wave. The threat is here and now.”