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Climate Scientists Debunk Claims That CO2 Can’t Warm Earth’s Surface
Carbon dioxide does indeed warm Earth’s surface despite claims on social media that “heat only goes up,” according to climate scientists who explain that greenhouse gases transfer heat in all directions through radiation.
A recent Facebook post claiming that atmospheric CO2 “no longer has any possible heating effect” once it reaches the air has been thoroughly refuted by experts. The post erroneously states that CO2 can only warm the atmosphere above us because “heat goes UP” and “heat does not suddenly come DOWN again, to suit somebody’s theory.”
Martin Jucker, a climate physicist at the University of New South Wales, explains that while warm air does rise through convection, CO2’s warming effect works primarily through a different mechanism—thermal radiation.
“CO2 in the atmosphere does not heat the atmosphere, but sends radiation coming from Earth’s surface back to the surface,” Dr. Jucker told AAP FactCheck. “Thus, the energy related to that radiation does not go out to space, but comes back down to Earth, heating the surface.”
This process functions as a form of insulation. Earth’s surface emits heat as longwave radiation, which atmospheric CO2 molecules absorb and then re-emit in all directions, including downward toward the planet’s surface. This prevents the heat from escaping into space, creating the greenhouse effect that warms our planet.
Steven Sherwood, another climate scientist at UNSW, notes that this downward radiation can be directly measured using scientific instruments called spectrometers. He quantifies the scale of this heat, explaining it’s “equivalent to roughly 100 billion blowtorches operating continuously” and is “fully sufficient to explain the observed global temperature rise over time, as verified by calculations.”
The latest Intergovernmental Panel on Climate Change (IPCC) report on climate science details these mechanisms thoroughly, providing comprehensive scientific evidence for how CO2 and other greenhouse gases warm the planet.
Dave Frame, a climate change physicist at the University of Canterbury, points out that the social media post fundamentally misunderstands how heating occurs. “A vast number of laboratory, atmospheric, and satellite studies have confirmed” that greenhouse gases trap outgoing radiation and re-emit it toward Earth’s surface, he says.
The Facebook post also questioned evidence of sea level rise, claiming measuring devices would need to be placed “in EVERY meter of water” and expressing skepticism about their existence since the poster hadn’t “collided with any of these measuring devices” while swimming or boating.
John Hunter, a sea level rise expert at the University of Tasmania, explains that sea levels are accurately measured worldwide through a sophisticated network of instruments. These include tide gauges at ports globally and satellites capable of measuring ocean heights over hundreds of kilometers.
“Scientists have put together observations of sea level from land-based and space-based instruments and come up with a consistent picture of the rate of sea-level rise and how it varies from place to place, and over time,” Hunter told fact-checkers.
While sea level rise rates vary by location and time period, the overall trend shows rising oceans in most places, with causes well understood by the scientific community.
The claims in the Facebook post exemplify how fundamental misunderstandings of climate science can lead to the spread of misinformation. Climate scientists emphasize that the evidence for CO2-driven warming is robust and supported by multiple lines of evidence from laboratory experiments, atmospheric measurements, and satellite observations.
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14 Comments
Helpful to get the physics explanation on how CO2 warms the Earth’s surface through radiative transfer, not just rising hot air. Appreciated the clear refutation of the misleading social media claim.
Grateful to see climate experts stepping in to thoroughly debunk the erroneous claim that CO2 can’t warm the Earth’s surface. Vital to rely on rigorous science rather than social media misinformation.
I’m glad to see this myth being thoroughly debunked with clear scientific evidence. It’s critical that we rely on expert climate scientists rather than misinformation on social media.
Appreciated the detailed breakdown of how CO2 warms the Earth’s surface through radiative heat transfer, not just rising hot air. Valuable to see the facts laid out to refute misleading claims.
Agree, the scientific evidence presented here is important for dispelling climate change myths.
Yes, this fact check provides a helpful explanation to counter the persistent myth about CO2 and heat.
This fact check does a good job of explaining the actual mechanisms of greenhouse gas warming, beyond the simplistic notion that ‘heat only rises’. Important to counter misinformation with scientific evidence.
Agreed, the detailed scientific explanation is valuable for improving public understanding of climate change.
Interesting to see the science behind how CO2 warms the Earth’s surface through radiative heat transfer, rather than just rising hot air. I appreciate the clear explanations from climate experts refuting the misleading claim.
The clarification on the mechanisms of greenhouse gas warming is helpful in understanding the complexities of climate science. It’s good to see the facts being laid out to counter misinformation.
This is an important fact check to counter the persistent myth that CO2 can’t warm the surface because ‘heat only rises’. The scientific explanation of radiative heat transfer is crucial for public understanding of climate change.
The physics behind how CO2 warms the Earth through radiative heat transfer is fascinating. Glad to see this myth being dismantled with clear scientific evidence from climate scientists.
This is an important clarification on the mechanisms of greenhouse gas warming. The explanation of radiative heat transfer is crucial for countering widespread misinformation on this topic.
Absolutely, relying on expert climate science is vital for public understanding of this complex issue.