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At least some journalists and scientists appear finally to be admitting that many people promoting the theory that humans are causing a climate crisis have been wildly exaggerating the likelihood the most extreme climate harms will occur.

Prior to the of the release of the Fifth Assessment Report from the Intergovernmental Panel on Climate Change (IPCC) on the purported human causes of climate change, researchers developed four different scenarios, referred to as, “Representative Concentration Pathways” (RCPs), to describe how carbon emissions might change through 2100. The most extreme of these scenarios, RCP8.5, projected a 500 percent increase in the use of coal, which it referred to as the “business as usual” scenario. IPCC projected RCP8.5 could result in a warming of more than 6 degrees Celsius by 2100, resulting in all manner of catastrophic consequences.

More than 2,000 research papers, including U.S. Fourth National Climate Assessment (NCA4) produced in late 2018 by holdovers from the former Obama administration, referenced RCP8.5, treating it as the most likely outcome of the present rate of human greenhouse gas emissions. The mainstream media counted these reports as authoritative and used them to shut any who disagreed with the IPCC’s claims out of news reports covering climate change, saying continued debate was not just unjustified, but, because of the seriousness of the purported crisis, dangerous.

The problem is RCP8.5 was never a likely outcome, and IPCC modelers knew this at the time they produced it.

Due to improved efficiencies and the increasing use of natural gas and renewable energy sources, global coal use was slowing in developing countries, and declining in the developed world, even before IPCC produced its RCP projections, including the extreme business as usual RCP8.5. Indeed, the chance of RCP8.5 of occurring is less than three percent. For political and economic reasons, deep state bureaucrats, crony capitalists, progressive politicians, the press, and government funded scientists, ignored this, instead treating RCP8.5 as if it were the most likely course for the world absent radical restrictions on greenhouse gas emissions.

The scientists involved with producing RCP8.5 now say they didn’t do a good job of communicating the likelihood of its projections of disaster coming to pass—Gee, ya’ think? I would argue careful calculation led to their silence for more than four years, in allowing the least probable of the climate scenarios they produced to be treated as the most likely to occur.

A recent paper by the Competitive Enterprise Institute notes, “[C]ontrarians have been documenting the implausibility of RCP8.5 for years, citing the very research allegedly confusing thousands of scientists.” CEI cites numerous peer-reviewed articles demonstrating the folly of treating IPCC RCP8.5 projections as if it were in any way representative of reality. Of course, truth being extremely inconvenient for their political agendas, climate activists, politicians, the press, and scientists benefitting from scaremongering conveniently ignored this research.

Thankfully, as bad as RCP8.5 projections of economic harm are, when compared to the estimated size of the future world economy, even they don’t amount to disaster.

Stan Liebowitz, Ph.D., the Ashbel Smith Professor of Managerial Economics at the University of Texas at Dallas, examined NCA4’s projections of economic harm using RCP8.5.

NCA4 estimates the dollar value of 22 different categories of potential damage in the United States from global warming in the year 2090, including destruction from rising oceans, mortality due to excessive heat or poor air quality, additional harm from diseases such as West Nile Virus, and the costs of repairing roads and bridges damaged from floods or erosion. NCA4 estimates the total costs of damages resulting from climate change in 2090 will top $507.6 billion.

“The simplest way to put the number in perspective is to compare this predicted 2090 loss with the predicted 2090 GDP [approximately $70 trillion],“ writes Liebowitz, … [meaning] the predicted climate change damages in 2090 represent slightly more than 0.7 percent of U.S. GDP. Thus the damage from climate change in NCA4’s worst-case scenario, according to our ‘best scientists and experts,’ is less than 1 percent of U.S. GDP in 2090.”

What is true of the United States should be equally true of the world as a whole. To paraphrase President Franklin Delano Roosevelt, “We have nothing to fear, but fear induced by the climate hype itself.”

H. Sterling Burnett, Ph.D.(hburnett@heartland.org)is a senior fellow on energy and the environment at The Heartland Institute, a nonpartisan, nonprofit research center headquartered in Arlington Heights, Illinois.