A movie questioning the role of humans in climate change has sparked claims that carbon dioxide (CO2) has never driven temperature increases in the past and therefore cannot cause global warming. This is misleading; experts told AFP the historical record shows clear evidence that greenhouse gas emissions are heating up the planet.
"'The question of whether CO2 drives the climate is easily resolved. You can look back in time over hundreds of millions of years—CO2 levels have changed radically many times,'" says Wide Awake Media, a popular conspiratorial X account, in an April 12, 2024 post.
"'Did this cause temperature change? No, absolutely not. CO2 has never driven temperature changes in the past. Never.'"
The post quotes Tom Nelson, the producer of a film titled "Climate: The Movie (The Cold Truth)."
Naomi Oreskes, a professor of the history of science at Harvard University (archived here), told AFP the claim spreading online is "based on a half-truth -- as so much disinformation is."
The UN Intergovernmental Panel on Climate Change (IPCC) says it is "unequivocal that human influence has warmed the atmosphere, ocean and land" -- and that CO2 is the main culprit (archived here and here).
"Scientists have worked very hard to rule out all other possibilities," Travis Rector, an astronomer at the University of Alaska-Anchorage (archived here), told AFP in 2022.
"The only explanation that is possible is the addition of these greenhouse gases through human activity."
Atmospheric concentrations of the main greenhouse gases (carbon dioxide, methane and nitrous oxide) between 1984 and 2022, based on data by the World Meteorological Organization
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'Large temperature swings'
NASA data showhuman activities have raised atmospheric CO2 by 50 percent in less than 200 years (archived here).
The influx of CO2 has trapped heat in the atmosphere, warming the planet by more than one degree Celsius above pre-industrial levels, according to IPCC scientists (archived here).
The greenhouse effect has made Earth warm enough for humans to survive comfortably. The natural phenomenon functions as an invisible blanket of nitrogen, oxygen and other gases that envelops our planet, allowing it to retain the Sun's heat (archived here).
However, human activities such as burning coal and oil inject additional CO2 into the atmosphere, which traps more solar radiation.
CO2 has not always been the historical driver of natural climate cycles. But Bärbel Hönisch, a professor at Columbia University's Lamont-Doherty Earth Observatory (archived here), told AFP that the greenhouse gas has "acted as an amplifier" -- a point demonstrated in multiple scientific studies and reports (archived here and here).
"Whether CO2 drove or only amplified temperature rise in the past is irrelevant for our current time," she said April 16, 2024. "Today we are increasing CO2 at a rate that may be faster than ever before in the geological record."
Yochanan Kushnir, another Lamont-Doherty Earth Observatory professor (archived here), concurred.
"CO2 concentration quickly rose from the pre-industrial level of about 280 parts per million (ppm) to 300 ppm in the early 20th century to about 425 ppm today -- way higher than at anytime during the last 800,000 years," he said April 23.
Hönisch said that "without the role of CO2," Earth "would not have experienced such large temperature swings."
'Overriding' orbital cycles
Earth has experienced long periods of extreme cold -- including ice ages, which represent regular cycles triggered by variations in the planet's axis and orbit around the Sun (archived here). While small, these changes have a powerful effect on how much heat reaches Earth.
Based on these orbital cycles, Hönisch said the planet should be heading toward a cooling phase (archived here).
"The fact that we are not heading that way is because of anthropogenic greenhouse gas emissions, which make the planet warmer than it should be at this time," she said.
Oreskes of Harvard University agreed.
"Today human-generated CO2 is driving warming, so much so that it has overridden the natural climate variability caused by orbital variation," she said.
"What is going on now is historically unprecedented, and that is precisely why it is alarming."
More of AFP's reporting on climate misinformation is available here.
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Welcome, folks, to Week in Review (WiR), TechCrunch's regular newsletter that recaps the week that was in tech. A total of 200 people were let go across Google’s “Core” teams, which included those working on app platforms and other engineering roles. Elsewhere, Tesla CEO Elon Musk gutted the company's team responsible for overseeing its Supercharger network in a new round of layoffs -- despite recently winning over major automakers like Ford and General Motors.
While the venture world is abuzz over generative AI, Dayna Grayson, a longtime venture capitalist who five years ago co-founded her own firm, Construct Capital, has been focused on comparatively boring software that can transform industrial sectors. All that said, they’re barreling toward the future and – seemingly successfully – dragging some staid industrial businesses along with them.
A small study led by researchers at the University of Glasgow and Northeastern University compared parrots’ responses when given the option to video chat with other birds via Messenger versus watching pre-recorded videos.
This week in AI, eight prominent U.S. newspapers owned by investment giant Alden Global Capital, including the New York Daily News, Chicago Tribune and Orlando Sentinel, sued OpenAI and Microsoft for copyright infringement relating to the companies' use of generative AI tech. “We’ve spent billions of dollars gathering information and reporting news at our publications, and we can’t allow OpenAI and Microsoft to expand the big tech playbook of stealing our work to build their own businesses at our expense,” Frank Pine, the executive editor overseeing Alden’s newspapers, said in a statement.
Hallucinations -- the lies generative AI models tell, basically -- are a big problem for businesses looking to integrate the technology into their operations. In a recent piece in The Wall Street Journal, a source recounts an instance where Microsoft's generative AI invented meeting attendees and implied that conference calls were about subjects that weren't actually discussed on the call. As I wrote a while ago, hallucinations may be an unsolvable problem with today's transformer-based model architectures.
Google has updated its Inappropriate Content Policy to include language that expressly prohibits advertisers from promoting websites and services that generate deepfake pornography.
MLB and Nike are making changes to the player uniforms for the 2025 season. The uniforms have faced heavy criticism for a variety of issues, including small lettering and discoloration from sweat.
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