by The latest calculations from several scientific agencies that show global heat records that destroyed the Earth last year may seem alarming. But scientists worry that what’s behind those numbers could be even worse.
The Associated Press news agency spoke to more than three dozen scientists about what the smashed records mean. Most say they fear an acceleration of climate change that is already on the brink of the 1.5C increase since pre-industrial times that nations hoped to stay within.
“The heat of the past calendar year was a dramatic message from Mother Nature,” says Katharine Jacobs, a University of Arizona climate scientist. Scientists say warming air and water are making deadly and costly heat waves, floods, droughts, storms and wildfires more intense and more likely.
Last year was particularly bad.
The climate behaved in strange ways in 2023
Average global temperatures have broken the previous record by just over 0.15C, by a wide margin, according to calculations released on Friday by America’s two top science agencies, Britain’s meteorological service and a private group founded by a climate skeptic.
Some of the scientists who made the calculations said that the climate was carried i strange ways in 2023. I wonder if man-made climate change and a natural El Nino have been contributed to by a freak blip or if “something more systematic is going on,” as NASA climate scientist Gavin Schmidt put it – including an acceleration much debated warming.
A partial answer may not come until late spring or early summer. That’s when strong El Nino – the cyclical warming of the waters of the Pacific Ocean which affects global weather patterns is expected to decrease. If the temperature of the sea, including deep waters, is constantly settling records well into the summer, like 2023, that would be a terrible tip, they say.
Nearly every scientist who answered AP questions blamed greenhouse gases for it fossil fuels as the biggest reason why the world has hit temperatures that human civilization is unlikely to have seen before. El Nino, bordering on ‘very strong’, is the second biggest factor, with other conditions far behind, they say.
The trouble with 2023, says NASA’s Schmidt, is that “it was a very strange year… The more you dig into it, the less clear it becomes.”
One part of that is the timing for when the big 2023 heat burst began, according to Schmidt and Samantha Burgess, deputy director of the European Copernicus Climate Service, which earlier this week put warming at 1.48C. above pre-industrial times.
Temperatures are usually higher than normal in late winter and spring, they say. But the highest heat in 2023 came in June and remained at record highs for months.
Deep ocean heat, a major player in global temperature, behaved in the same way, Burgess says.
Is global warming accelerating faster than predicted?
Former NASA climate scientist James Hansen, often considered the father of global warming science, theorized last year that heating was accelerating. While many of the scientists contacted by the AP said they doubt it’s happening, others were adamant that the evidence so far only supports a steady and long-predicted increase.
“There is some evidence that the rate of warming over the last decade or so has been slightly faster than the previous decade or so — which meets the mathematical definition of acceleration,” says UCLA climate scientist Daniel Swain. “However, this is also very much in line with predictions” that warming would occur speed up at a certain point, especially when particulate pollution in the air decreases.
The US National Oceanic and Atmospheric Administration (NOAA) calculated that the Earth’s average temperature would be 15.08C in 2023. That’s 0.15C warmer than the previous record set in 2016 and 1.35C warmer than pre-industrial temperatures.
“It’s almost as if we peed ourselves off the stairs [of normal global warming temperature increases] on a slightly warmer regime,” says Russ Vose, global monitoring chief for NOAA’s National Centers for Environmental Information. He says he sees the acceleration of warming.
NASA and the UK Met Office had the warming since the mid-19th century slightly higher at 1.39C and 1.46C respectively. Records date back to 1850.
The World Meteorological Organization, which combines the measurements announced on Friday with Japanese and European calculations released earlier this month, put 2023 at 1.45 degrees Celsius warmer than pre-industrial temperatures.
Can a warming limit of 1.5C still be achieved?
Many of the climate scientists saw little hope of stopping warming at the 1.5-degree target that was called for in the 2015 Paris agreement that sought to avoid the worst consequences of climate change.
“I don’t think it’s realistic that we can limit warming [averaged over several years] to 1.5C,” says Woodwell Climate Research Center scientist Jennifer Francis. “It is technically but politically possible impossible.”
“The slow pace of climate action and the constant disinformation that drives it is never about a lack of science or even a lack of solutions: it has always been, and still is, about a lack of solutions. political will,” says Katharine Hayhoe, chief scientist at The Nature Conservancy.
NASA and NOAA said the last 10 years, from 2014 to 2023, are the last 10 years. warm years they have measured. This is the third time in the last eight years that a global heat record has been set. Randall Cerveny, an Arizona State University scientist who helps coordinate record keeping for the WMO, says the biggest concern is not that records were broken last year, but that they are happening so often.
“The rapidity of continuous change is the scariest thing to me,” says Cerveny.
Cornell University climate scientist Natalie Mahowald says, “This is just a taste of what we can expect in the future, especially if we continue to fail to rapidly cut carbon dioxide.”
That’s why so many scientists contacted by The Associated Press are concerned.
“I’ve been concerned since the early 1990s,” says Brown University climate scientist Kim Cobb. “I’m more worried than ever. My concern increases every year when global emissions move in the wrong direction.”
