Why the Discredited Cloud Theory of Global Warming Won’t Die

Richard Lindzen's rejected idea that clouds can help prevent catastrophic climate change keeps resurfacing, thanks largely to nonscientist skeptics.

Two mobile facilities designed to measure greenhouse gases.
Two mobile facilities designed to measure greenhouse gases. The system, which was built by researchers at Sandia National Laboratories, was deployed to the Atmospheric Radiation Measurement (ARM) facility in Oklahoma. Credit: Sandia National Laboratories

Share this article

In climate science, some ideas seem to live forever like vampires, despite repeated attempts to slay them.

A New York Times story last week focused on one of those ideas and the man behind it: Richard S. Lindzen, a professor of meteorology at the Massachusetts Institute of Technology. The story caught the eye of climatologists everywhere.

Lindzen believes clouds will be our savior, because he says they’ll help prevent catastrophic impacts from global warming. His pitch has made him the darling of naysayers and a pariah among the vast majority of climate scientists who find his research badly flawed and his conclusions unsupported.

Joel Norris, a professor of atmospheric and climate science at the Scripps Institution of Oceanography in San Diego, is among those who have followed Lindzen’s cloud theory over the years. In an interview with InsideClimate News, Norris said it’s unusual for discredited scientific ideas to keep resurfacing, as Lindzen’s have for more than a decade.

What usually happens, Norris says, is the scientific community dissects a faulty theory, finds its flaws, and then dismisses it. After that, you don’t hear much about the idea.

But that’s not the way things work in the world of climate science, where people outside the scientific community may have a vested interest in recirculating discredited ideas.

Lindzen has many people willing to support his cloud theories. He has testified before congressional committees chaired by global warming skeptics, written commentaries that have appeared in the Wall Street Journal, and is treated as a hero by groups around the world fighting proposals to institute a carbon tax, including the Heartland Institute.

“You have people who keep propping it [discredited theory] up,” said Norris, whose specialty is long-term changes in clouds. “Lindzen may still hold to it, but no one would still be listening to him. He wouldn’t be given a platform.”

Norris and other cloud scientists acknowledge there’s not a vast data set on the inner working of clouds today, much less in the future. Climate change skeptics tend to seize on that void.

Lindzen doesn’t dispute that adding CO2 to the atmosphere could cause an increase in temperatures. His view of what happens later is where he parts with most climate scientists. He believes Earth will be able to self-regulate its temperature, like a thermostat, because of clouds.

Dense low clouds do tend to cool the earth’s surface by reflecting most sunlight back into space. Thin high clouds, mainly ice crystals, let most sunlight through, then trap the reflected heat near the surface.

Through a mechanism he calls the iris effect, Lindzen asserts that a warmer atmosphere will have fewer high clouds—and that without those clouds to trap the rising heat, the upper atmosphere would be better able to vent the heat into space.

Norris says Lindzen starts with the assumption that the earth isn’t very sensitive to greenhouse gases, then jumps to faulty conclusions that are driven by what he’s hoping to find, not by what the data actually show.

“It comes down to looking at the relationship between clouds in the present-day climate and then trying to infer what will happen in the future. [His] interpretation of what will happen is not well supported.”

Norris used this analogy: If someone were to look off the coast of San Diego during a strong Santa Ana wind event, they might see a brown line of air pollution—and no clouds. To conclude that pollution is keeping the clouds away, not the strong offshore winds, would be the kind of erroneous leap and dot-connecting that Lindzen makes in his research, Norris says.

While nonscientists aren’t prohibited from joining dots without solid data to support the connection, that process is supposed to be unacceptable to scientists.

Norris admits there is still much to learn about how clouds operate, and there is no consensus on what their overall impact will be on a warmer planet. Estimates range from negligible to significantly adding to the warmth.

“Clouds are complicated,” he said. “It’s difficult to represent them in a global climate model. Clouds are small.”

Another problem: Scientists don’t have a good, continuous record of clouds, a stable monitoring system, or an agency charged with monitoring clouds.

Norris said the best cloud record, produced by a couple of NASA’s weather satellites, only goes back about 10 years.

If science can’t yet paint a detailed picture of future cloud conditions, using faulty science to fill out the frame isn’t the answer.

“A lot of the time, I don’t know what’s there,” Norris said of his own research. “Sometimes, you do have a hypothesis, and if it’s not borne out, you abandon it. But I get the impression that Lindzen just looks for something else to support it.”

Data Problem May Worsen

A report by the National Research Council warns that the U.S.’ earth observing satellite system is beginning a rapid decline in capability, as long-running missions end and key new missions are delayed, lost due to launch failures or cancelled.

“The projected loss of observing capability will have profound consequences on science and society, from weather forecasting to responding to natural hazards,” said Dennis Hartmann, professor of atmospheric sciences at the University of Washington, Seattle, and chair of the committee that wrote the report. “Our ability to measure and understand changes in Earth’s climate and life support systems will also degrade.”

Budgets for NASA’s earth science program are inadequate to meet pressing national needs and are likely to remain so, the report says. Another problem is the shortage of reliable and affordable satellite launch capability.

The study was sponsored by NASA.

Growing Chorus for Climate Action

Tampa, Fla., is the latest city to join the growing list of U.S. cities that are urging national leaders to use the Clean Air Act to reduce greenhouse gas pollution to head off catastrophic climate change.

“Climate change is a grave threat to the economy and environment of Tampa Bay, so the city council is urging the federal government to take immediate action through the Clean Air Act,” said Mary Mulhern, the Tampa city councilmember who led the effort to pass the resolution. “We’re proud to join almost two dozen other cities in urging the Environmental Protection Agency to move swiftly.”

Global warming poses a threat to South Florida’s tourism and agricultural industries, Mulhern said. Rising sea levels and retreating shorelines will leave the Tampa Bay area more vulnerable to hurricanes, and salt water intrusion from sea-level rise could endanger aquifers used for water supplies, according to a 2008 report from the Governor’s Action Team on Energy and Climate Change.

Similar resolutions have been approved in Pinecrest, Fla.; Cincinnati and Oberlin, Ohio; Seattle, Wash.; Kansas City, Mo.; Albany, N.Y.; Tucson, Ariz.; Boone, N.C.; Pittsburgh, Penn.; Minneapolis, Minn.; Santa Fe, N.M.; Cambridge, Mass.; Madison and Milwaukee, Wis., and Arcata, Richmond, Berkeley, Oxnard, Santa Cruz and Santa Monica, Calif. Several other cities around the country will be considering resolutions over the next few months.