For years, the fossil-fuel industries have been telling us that global warming is a hoax based on junk science.

But now these industries are floating an intriguing new argument: They’re admitting that human use of coal, oil and gas is causing carbon dioxide in the atmosphere to rise — but they’re saying this is a good thing. We need more CO2 in our lives, not less.

“CO2 is basically plant food, and the more CO2 in the environment the better plants do,” proclaimed Roger Bezdek, a consultant to energy companies, at an event hosted Monday by the United States Energy Association, an industry trade group.

The session, at the Ronald Reagan Building in downtown Washington, was devoted to demonstrating that “CO2 benefits clearly outweigh any hypothesized costs.” And though Bezdek is an economist, not a scientist, he played one on Monday — showing a PowerPoint presentation that documented a tree growing faster when exposed to more carbon dioxide.

“CO2 increases over the past several decades have increased global greening by about 11 percent,” the consultant said. Higher carbon levels in the atmosphere will boost worldwide agricultural productivity by $10 trillion over the next 35 years, he added.

And this doesn’t include the indirect benefits of good-ol’ CO2. “Over the past two centuries, global life expectancy has more than doubled, population has increased eightfold, incomes have increased 11-fold. At the same time, CO2 concentrations increased from 320 ppm to about 400 ppm,” Bezdek said, using the abbreviation for parts per million. The benefits of CO2, he said, exceed its costs by ratios of between 100-1 and 900-1. A chart helpfully illustrated this “Close Link Between CO2 & GDP.”

I’m neither a scientist nor an economist, but I’ve heard that correlation is not the same as causation. I pointed out to Bezdek that increasing energy use fueled the economic growth, and CO2 was just a byproduct. So wouldn’t it make more sense to use cleaner energy?

“Fossil fuels will continue to provide 75, 80, 85 percent of the world’s energy for at least the next four or five decades,” he asserted. And even if we could reduce CO2, we shouldn’t. “If these benefits are real — and there have been five decades and thousands of studies and major conferences that pretty much have proven they are — then maybe we shouldn’t be too eager to get rid of CO2 in the atmosphere.”

This was some creative thinking, and it took a page from the gun lobby, which argues that the way to curb firearm violence is for more people to be armed.

Another questioner at the event asked Bezdek if he had considered ocean acidification, the release of methane gases, pollution and other side effects of rising CO2. This did not trouble him. “As you develop and you become wealthier,” he explained, “you have the wealth to clean up the mess.” He went on to point out that “35,000 people every year in the United States die in automobile accidents, but the solution is not to ban automobiles. You try to make them safer.”

And the solution to climate change is not to ban energy but to make it cleaner.

The U.S. Energy Association membership comes from various sectors but includes big petroleum companies and utilities. Bezdek seemed to have a special place in his heart for coal, “the major world energy source of the past, present and future . . . lifting hundreds of millions of people out of poverty.”

The presentation began as a standard recitation of the climate-change denial position, that “there’s been no global warming for almost two decades” and that forecasts are “based on flawed science.”

But then Bezdek pivoted into a robust defense of carbon dioxide’s benefits. “These days, CO2 seems to be blamed for everything,” he lamented, but the much-maligned gas is what’s keeping the world from an economic collapse so deep “you’d look upon North Korea as an economic consumer’s paradise, literally.” He mocked European efforts to use renewable fuels (“You can’t check your e-mail today because the wind isn’t blowing”) and he said that in the United States, “inability to pay utility bills is the second-leading cause of homelessness.”

Clearly, more CO2 would make us all breathe easier. “Controlled studies indicated that twice today’s levels would be very good for agriculture,” he said, “and below certain levels . . . plants wouldn’t grow and we wouldn’t live.”

Luckily, we need not worry about that, because Bezdek is confident fossil fuels will continue to prevail. In “2070 will we have a new and different energy source?” he asked. “Maybe, but I wouldn’t hold my breath.”

Definitely don’t hold your breath, sir. We need all the CO2 we can get.

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