Two Fort Collins scientists want to change how the world views the connection between human activity and global warming.

However, Ned Nikolov and Karl Zeller say they’ve had a hard time getting the scientific world to hear them out, let alone take them seriously.

They’ve gone to great lengths — including the use of pseudonyms — to publish papers challenging the concept that greenhouse gases such as carbon dioxide, water vapor and methane in the atmosphere contribute to the warming of Earth.

Their rejection of status-quo thinking on atmosphere and climate change has led to scorn from fellow scientists and longtime friends. They’ve been lumped into the category of “climate deniers.” Their wives think they’re crazy, Zeller said.

“We’re not deniers, we’re scientists,” he said.

Duggan:Words matter to climate action advocates

Zeller and Nikolov, who have doctorate degrees and years of experience in physical sciences, found that the mean surface temperature on Earth is not controlled by humans pumping greenhouse gases into the air but rather by solar radiation and atmospheric pressure.

The researchers believe their findings represent an emerging paradigm in climate science. Implications include that all the effort going toward reducing carbon in the atmosphere is a costly waste of time, Zeller said.

Scott Denning, a professor of atmospheric science at Colorado State University who has worked extensively on climate change, said the mathematical model developed by Zeller and Nikolov does not stand up to scientific scrutiny.

The pair’s analysis is “too simple” in explaining the effects of atmosphere on temperature and does not adequately take into account thermodynamics, he said. A bigger problem is leaping to the conclusion that there is no greenhouse effect based on the model.

Environment:Wellington grapples with 'disgusting' drinking water

Zeller and Nikolov said Denning and other critics either do not understand the model or have not read their work. Zeller challenged critics to get out of the “box” of conventional thinking in an email to the Coloradoan.

“After honestly reading the paper and taking the time to understand the terms, the data, the math and the gas physics, please document one significant error in the data, or the math, or the physics and allow us to explain it,” he wrote.

Disagreeing with current greenhouse effect theory does not constitute an error, Zeller added.

Fighting prejudice against anything but accepted thinking on climate change has been a struggle for Nikolov and Zeller. Their work and skepticism became known within the scientific community to the point they could not get papers on their research reviewed for publication.

Editors rejected unread manuscripts based on what turned up in Google searches of their names, Zeller said.

So they changed the spelling of their names. Karl Zeller became Lark ReLlez; Ned Nikolov became Den Volokin. A paper on the thermal effect of Earth’s atmosphere was accepted and published in 2014.

“We thought in order to give the reviewers an opportunity to only focus on the content of the paper and not be distracted by anything else, we have to hide our identities,” Nikolov said. “And it worked.”

Related:EPA boss Pruitt visits Colorado to discuss coal mining, water rules

The paper was later retracted because of the use of pseudonyms — not its science, he said.

A second paper about their model was published this year in the journal Environmental Pollution and Climate Change under their real names. More papers are in the works.

Nikolov works as a physical scientist for the U.S. Forest Service, His research on climate change is done on his own time. Zeller is a retired Forest Service meteorologist.

History is rife with examples of researchers challenging and ultimately disproving long-held scientific theories, Nikolov said.

Challengers of the status quo typically are ridiculed and dismissed by the scientific community when first offering their ideas, he said. If the science is sound and provable, denial eventually gives way to acceptance.

Global warming and the science around it have taken on moral and political implications for people on all sides of the issues to the detriment of scientific inquiry, he said.

“At the end of the day, climate is a physical phenomenon,” Nikolov said. “It has no moral values, it has no religious values. And people who try connect moral or religious values with climate (are making) a big mistake.”

State:Colorado's governor endorses global climate pact

Denning said the scientists are clearly sincere in their beliefs, but they also are naïve in rejecting outright so much of what is known about climate science.

He said they are not comparable to Copernicus and Galileo, whose work challenging the adopted model of an Earth-centered universe in favor of a sun-centered model was labeled heresy before it was accepted.

“Just because everybody thinks you’re wrong doesn’t mean you’re right,” he said. “That just doesn’t hold logical water.

“If I start saying the world is flat, that doesn’t mean it is because everybody else thinks it’s round. It doesn’t really work that way.”

Kevin Duggan is a Coloradoan senior reporter covering local government. Follow him on Twitter, @coloradoan_dugg, and on Facebook at Coloradoan Kevin Duggan.

Local:This Fort Collins man wants a ban on big, brittle trees

See for yourself

Correction: The name of one of the papers was incorrect in an earlier version of this story. It has now been corrected.

To read academic papers by Ned Nikolov and Karl Zeller, see:

"New insights on the physical nature of the atmospheric greenhouse effect deduced from an empirical planetary temperature model" (2017): Environmental Pollution and Climate Change – http://bit.ly/2sUC4FJ

"On the average temperature of airless spherical bodies and the magnitude of Earth's atmospheric thermal effect" (2014): SpringerPlus – http://bit.ly/2hlPqp3

Behind the theory

Using data from NASA, Ned Nikolov and Karl Zeller developed a mathematical model that predicts the mean global temperature for the surface of a rocky planet with or without an atmosphere.

They say the model accurately reflects the average long-term temperature of Earth as well as the moon, Mars, Venus, Triton, a moon of Neptune, and Titan, a moon of Saturn.

Surface air pressure and solar radiation are the key drivers of temperature. The implication is that the chemical composition of an atmosphere does not affect surface temperatures of a planet, Nikolov said.

That means atmospheric greenhouse gas theory, which was first postulated by scientists in the 19th century, is fundamentally flawed, he said. It is based on misinterpreted laboratory experiments rather than planetary observations.

“We have zero empirical evidence that a free convective atmosphere can trap heat … it’s all (computer) model based,” he said.

Scott Denning, atmospheric science professor at Colorado State University, said finding that solar radiation and atmospheric pressure affect planetary surface temperatures is not surprising. The model is a “curve-fitting” exercise that relies on manipulation to get results.

“They have two variables that are related to surface temperature and tweaked a bunch of dials so that they can predict an average temperature,” he said. “Using the data, they have figured out what the fudge factors have to be to make it work out.”

Gas theory is the basis of modern-day scientific knowledge in many fields, including astronomy and spectrometry, he said. Denying its principles, which have been tested countless times in laboratories and in the field for more than 100 years, “is not convincing.”