LOS ANGELES — Dr. Wie-Hock “Willie” Soon of the Harvard-Smithsonian Center for Astrophysics addressed a gathering of the American Freedom Alliance on Thursday night at the Luxe Hotel, describing the current state of debate about climate change as “spitting science in the face” and “treating science like a piece of rubbish.”

Mixing humor and science, he entertained the gathering as he made the case for skepticism about climate change.

He began by mocking the degree to which carbon dioxide was treated like a toxic gas by proponents of radical policies on climate change. “Next it will be oxygen, it will be anything that you want on the chemical table,” he joked.

“The Sun is a primary driver of climate change — and has a far greater impact than changes in CO 2 ,” he said, in a slide presented to the packed audience of about 100 conservatives.

Another slide added: “Climate science is dangerously corrupted and co-opted by multiple anti-science forces and players.”

To the amusement of the audience, Dr. Soon played a clip of Al Sharpton mocking him on MSNBC, pointing to research funding he had received from fossil fuel companies. “It is really, truly, a badge of honor, Rev. Al Sharpton, to be accused by you of a conflict of interest,” he said.

Dr. Soon called much of the reporting about his work in the mainstream media “fake news.” And he mocked the fads and fashions that have sprung up around climate change.

For example, he said, the ”locavore” movement, which stressed eating locally-produced food to save energy, actually increased greenhouse gases, because of the energy efficiencies achieved by larger and more established farms that benefited from economies of scale.

He also mocked California politicians for their statements on science — especially Governor Jerry Brown and former Governor Arnold Schwarzenegger. In 1977, he pointed out, Gov. Brown had warned of a drought of “immeasurable magnitude” — a meaningless phrase, in scientific terms.

The movement toward renewable energy sources, he said, was not a sign of progress, but regression toward the lower energy densities of the pre-industrial age. He also likened belief in carbon “pollution” to the superstitious beliefs of primitive civilizations, illustrating his point with a 1933 newspaper article describing a drought in Syria that was blamed by locals on yo-yo toys.

He then launched into his data-heady scientific presentation in earnest. For all the focus on carbon dioxide, the most important greenhouse gas in the climate system was water vapor, he said. And carbon dioxide, he noted, was not a “pollutant,” as the term was conventionally used.

While it was true that the atmospheric concentration of carbon dioxide had been increasing, he said, and had passed 400 parts per million, the dominant effect of water vapor had helped flatten the greenhouse effect, such that the rise of global surface temperatures had slowed significantly.

He said that some climate scientists manipulated graphs to make climate change seem more severe than it was — for example, by representing temperature anomalies rather than absolute temperatures.

His latest work, he said, was in understanding how temperature data sets were constructed. He and his colleagues were examining data gathered in rural areas, to remove the distortion of measurements in urban areas. They found that there was, in fact, some surface temperature warming, albeit less severe than conventional data sets showed. But the effect, he said, was more likely the result of fluctuations in energy output from the sun, which in turn affected water vapor.

The major effect of cutting carbon dioxide emissions to zero, he said, would be “to kill and hurt poor people and greatly harm animals and the environment.”

In the past, Dr. Soon noted, the left had attacked his research because he had taken funding from fossil fuel companies. He cited the New York Times as one of his chief antagonists, after it ran a disparaging profile of him in 2015.

As a result, he said, he had not accepted any funding for his latest research on the composition and manipulation of climate data sets.

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. He was named one of the “most influential” people in news media in 2016. His new book, How Trump Won: The Inside Story of a Revolution, is available from Regnery. Follow him on Twitter at @joelpollak.