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Last year was the hottest ever recorded in Texas based on average temperature, according to new data from the National Oceanic and Atmospheric Administration, a record that follows a global trend as climate change advances.

The average temperature in Texas measured 68.1 degrees last year, said John Nielsen-Gammon, the state climatologist. That’s 0.3 degrees higher than the previous record set in 2012.

The heat came early — on June 20 Del Rio hit 113 degrees while San Angelo hit 114 — and much of the state remained well into triple digits throughout the summer. The June 24 high of 119 degrees in Big Bend National Park was one degree below the state's all-time daily record.

It’s a continuation of a broader warming trend, Nielsen-Gammon said. Every year since 2000 in Texas has been warmer than the 20th century average. Last year was a whopping 3.5 degrees hotter than the 20th century average in the state.

“That consistent warmth is because of climate change,” Nielsen-Gammon said.

NOAA plans to announce Friday how 2023 temperatures ranked globally. Nationally, 2023 was the fifth-warmest year in the contiguous United States — not counting Alaska and Hawaii — since federal record keeping began in 1895, according to NOAA. Other states that recorded their hottest years last year were Louisiana, Massachusetts, Mississippi and New Hampshire.

Humans are causing changes to the atmosphere because of activities such as burning coal, oil and gas, which release greenhouse gas emissions that trap heat. Texas produces more oil and gas than any other state in the nation.

Andrew Dessler, a professor of atmospheric sciences at Texas A&M University, said temperatures fluctuate from region to region over time in part because of randomness in the weather, but baseline temperatures continue to rise.

He said by the time his 18-year-old twins are middle aged, he expects that 2023 could feel like an average summer to them. And when they are old, they might remember 2023 as a relatively cool summer.

“You can think of (2023) as kind of a preview of the future and it's not pretty,” Dessler said.

Extreme heat is dangerous to human health, causing heat stroke and other potentially fatal conditions, said Luke Metzger, executive director of Environment Texas. Metzger’s son plays high school football in Texas and last summer came home with signs of heat exhaustion, he said.

The heat can be especially dangerous for those who work outdoors and low-income people who don’t have air conditioning. Studies have shown that it has even more wide-ranging impacts, from increased aggression in people to damaging crops and worsening smog.

“We’re going to be forced to be trapped in our homes more and more and not able to spend time outside,” Metzger said. “So I think that’s, as much as everything, it’s just a huge loss to our quality of life.”

Disclosure: Texas A&M University has been a financial supporter of The Texas Tribune, a nonprofit, nonpartisan news organization that is funded in part by donations from members, foundations and corporate sponsors. Financial supporters play no role in the Tribune's journalism. Find a complete list of them here.

This article originally appeared in The Texas Tribune at https://www.texastribune.org/2024/01/11/texas-2023-hottest-year/.

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