The summer of 2023 behaves like a broken record on broken records.
Almost every major climate-monitoring organization has proclaimed June the hottest June ever. Then July 4th became the world’s hottest day, albeit unofficially, according to the University of Maine’s Climate Reanalyzer. It was quickly overtaken by July 5 and 6. Next comes the somewhat more official hottest week, put on the books by the World Meteorological Organization and the Japan Meteorological Agency.
With a summer of extreme weather records dominating the news, meteorologists and scientists say records like these provide insight into the big picture: a planet warming due to climate change. It’s an image that comes in the vibrant reds and purples representing the heat on daily weather maps online, in newspapers and on TV.
Beyond the cards and numbers, these are real misdeeds that kill. More than 100 people have died in heat waves in the United States and India so far this summer.
Records are crucial for people who design infrastructure and work in agriculture because they need to plan for worst-case scenarios, said Russell Vose, director of the National Oceanic and Atmospheric Administration’s climate analysis group. He also chairs a National Records Committee.
In the past 30 days, nearly 5,000 heat and precipitation records have been broken or equaled in the United States and more than 10,000 records set worldwide, according to NOAA. Cities and towns in Texas alone have set 369 daily high temperature records since June 1.
Since 2000, the United States has set about twice as many records for heat as for cold.
“The records go back to the late 19th century, and we can see there’s been a decade-over-decade increase in temperatures,” said Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies, custodian of the agency’s climate records. “What is happening now certainly increases the odds that 2023 will be the hottest year on record. My calculations suggest that there is, right now, a 50-50 chance.
The larger the geographic area and the longer the period over which the records are set, the more likely the conditions are to represent climate change rather than daily weather patterns. So the world’s hottest June is “extremely unlikely” without climate change, unlike a city’s daily record, said Texas state climatologist John Nielsen-Gammon.
Still, some local specifics are striking: Death Valley flirted this summer with the hottest temperature in modern history, though that record of 134 degrees Fahrenheit (56.7 Celsius) is disputed.
Phoenix made headlines among major US cities on Tuesday when it marked the 19th straight day of relentless mega heat: 110 degrees Fahrenheit (43.3 Celsius) or higher. It continued, reaching a 22nd straight day on Friday. The daytime heat was accompanied by a record streak of nights that never fell below 90 degrees Fahrenheit (32.2 degrees Celsius).
“Everyone is drawn to extremes,” Vose said. “It’s like the Guinness Book of World Records. Human nature is simply drawn to extreme things out of curiosity.
But numbers can be wrong in what they describe.
The scientific community “doesn’t really have the vocabulary to communicate how it feels,” said Chris Field, a Stanford University climatologist who co-chaired a groundbreaking 2012 United Nations report warning of the dangers of extreme weather from climate change.
“I don’t think it captures the human sense, but it really underscores that we live in a different world,” Field said of the recordings.
Think of individual statistics as brushstrokes in a painting of the global climate, said Natalie Mahowald, a climatologist at Cornell University. Don’t fixate on a specific number.
“Details matter of course, but what really matters, especially for Impressionist painting, is to step back and look at everything that’s going on,” Mahowald said.
She and other climate scientists say long-term warming from burning coal, oil and natural gas is the main cause of rising temperatures, along with occasional increases from natural El Nino warming in parts of the Pacific, as the planet is experiencing this year.
El Niño is a natural temporary warming of parts of the Pacific that changes weather patterns around the world and adds an extra boost. An El Nino formed in June and scientists say this one looks strong. Over the past three years, El Nino’s cool flip side, La Nina, has toned down the heat that humans cause a bit.
A super El Nino sent global temperatures soaring in 1998, then was followed by less warming and even stable temperatures for a few years until the next big El Nino, Mahowald said.
The weather won’t get worse every year and it shouldn’t become a common expectation, but it will intensify in the long run, she said.
Richard Rood of the University of Michigan used to blog about weather records for Weather Underground, but in 2014 he got fed up with the ever-new extremes and quit.
“I think we need to get away from that kind of record-breaking sensationalism on some level and really get to work,” he said, addressing the need for people to adapt to a warmer world and to get serious about reducing emissions causing hotter and more extreme weather.
NOAA tracks weather observations from tens of thousands of stations across the United States and its global calculations incorporate data from more than 100,000 stations, Vose said.
When these records arrive, the agency checks their quality and calculates the historical place of the numbers. NOAA’s National Center for Environmental Information in North Carolina is the arbiter of national records, while local National Weather Service offices handle those for individual cities, Vose said.
A special international committee looks after world records, and sometimes scientists disagree about the reliability of 100-year-old data. These disagreements come into play on issues such as determining the hottest temperature recorded on Earth.
Validating records takes time. Due to a backlog of extreme weather events to analyze, officials haven’t finished approving Death Valley’s 2020 and 2021 record highs of 130 degrees Fahrenheit, Vose said.
“Our main job is to keep score, which means what happened? How unusual was that?” He asked. “It’s not like we take much pleasure in saying it was the hottest year on record. Still.”
It’s the big picture that matters, said Northern Illinois University climatologist Victor Gensini.
“Look at them all together in the overall sense of atmospheric orchestra,” Gensini said. “There are so many clear signs that we just don’t live in the same kind of climate that we used to.”
