Ahead of the Climate Action Summit that will bring together world leaders in New York on Sept 23, exaggeration about global warming is greater than ever. While some pundits continue, incorrectly, to insist that global warming is a made-up story, far more insist, also incorrectly, that we face an imminent climate crisis.

Adding to the polarization on the topic makes it impossible to engage in sensible policy discussion. For example, we are constantly told that climate change is to blame for an increase in extreme weather conditions such as flooding, droughts and cyclones. But the UN Intergovernmental Panel on Climate Change has found the evidence does not support claims that floods, droughts and cyclones are increasing.

The scientists have said, "there is low confidence in a global-scale observed trend" in drought, a "lack of evidence regarding the sign of trend in the magnitude and/or frequency of floods on a global scale" and "no significant observed trends in global (cyclone) frequency over the past century."

What's more, the scientists have found that current human-caused global warming cannot reasonably be linked to any of these extreme weather phenomenon-"globally, there is low confidence in attribution of changes in (cyclone) activity to human influence", "low confidence in detection and attribution of changes in drought" and low confidence "that anthropogenic climate change has affected the frequency and magnitude of floods". This doesn't mean there is no problem－just that the facts matter.

What's behind the overblown rhetoric? Nearly three decades of policy failure. Promises made in Rio de Janeiro in 1992 and the Kyoto Treaty in 1997 to reduce carbon emissions achieved little or nothing. Three years into the Paris climate treaty, just 17 countries are on track-including Samoa and Algeria which promised very little. In fact, since climate talks began in 1992, the world has emitted as much carbon dioxide from fossil fuels as all of humanity did before that from the beginning of time.

The reason for this persistent failure, and the cause of today's exaggerations, is that policies to cut carbon emissions are incredibly expensive. The Paris Agreement is likely to cost between $1 trillion and $2 trillion a year, making it the costliest treaty in history.

And it's eye wateringly expensive to cut net emissions to zero. Although many politicians casually promise this should be the goal, few dare ask how much it will cost. A report commissioned by the New Zealand government found that achieving "net zero" emissions by 2050 would cost that country more than its entire current annual national budget every single year, and that's a best-case scenario, with costs more realistically doubling to 32 percent of GDP.

Proponents of vastly expensive climate policies appear to believe that the only way to overcome these exorbitant costs with voters is by scaring people silly.

Unfortunately, this approach is unlikely to work. Not only is it turning climate unnecessarily into a more polarizing issue, but also it could damage the credibility of science, as research is being increasingly seen as a partisan attempt to push a particular policy rather than a disinterested search for truth.

Even as a political strategy, it seems destined to fail, for as costs mount, we will see more street protests such as those in France, or eventual ballot losses like those in Australia, Brazil and the Philippines as voters turn to politicians who promise to reverse expensive climate policies.

Compare proposals to spend many thousands of dollars on climate with a new survey showing nearly seven-in-10 Americans would vote against spending just $120 each per year to combat climate change.

There is a far more sensible approach: Instead of scaring voters to accept fossil fuels costing more, we should innovate the price of green energy－when it becomes cheaper than coal and oil, everyone would switch.

Since the 1980s, OECD countries' spending on low-carbon research and development has slid from 0.06 percent of GDP to less than 0.03 percent. We can (and should) invest a lot more on green R&D. It would be much cheaper than current policies and be much more likely to succeed.

We can only reclaim the pragmatic center of the debate if we stop accepting the relentless climate exaggerations. Climate change is a problem, and it needs a smart and cost-conscious solution in order to address it.

The author is president of the Copenhagen Consensus Center. The views don't necessarily represent those of China Daily.