Reality can be profoundly persuasive. As Americans sweat out one of the hottest summers on record, we’ve watched in dismay as drought has withered endless acres of crops and pushed the federal government to declare “natural” disasters in more than half the nation’s counties.

As temperatures have shot up, so has the number of people accepting the scientific consensus on global warming. Seventy percent of respondents to a recent University of Texas poll believe the climate is changing, and about two-thirds of respondents to a Washington Post poll in July want the United States to be a world leader in addressing the problem.

Even Richard Muller, a Koch brothers-funded climate-change denier, has declared that he now agrees with the position long held by the overwhelming majority of scientists and scientific organizations. Climate change is real, say the experts - and really dangerous.

The good news is that we may finally be ready to move from debating climate change to actually doing something meaningful about it. The bad news? We’ve lost many years in which progress should have been made to a corporate-funded disinformation campaign.

Time is running out. Our actions in the next few years will decide whether we can head off climate change’s worst effects – and that makes it critical not to buy into these five dangerous myths:

Myth #1: It’s all China’s fault.

Reality: America must do far more to cut emissions for both moral and practical reasons. Some U.S. politicians have long used China’s growing emissions as an excuse for inaction. But China has dramatically ramped up solar power use and still lags far behind the U.S. in per-capita emissions. On a historical, cumulative basis, we are the world’s single largest emitter.

And we’re really kidding ourselves when we compare current U.S. pollution levels only to very recent, high-emissions years. The United States agreed, with the rest of the world, to use 1990 as the “baseline year” for comparing emissions levels, to avoid cheating on emissions reduction targets. While it is certainly good that our emissions have fallen recently, we must not forget that our emissions have increased more than 10 percent since 1990 – nor try to change the rules of the game by insisting on a later baseline year to avoid accountability for our pollution.

China’s growing emissions are a problem, of course – but what’s the best way to inspire change? A huge coastline and drought-vulnerable agriculture give China extra incentive to fight global warming, but developing countries rightly insist on meaningful U.S. cuts – that’s the only fair and politically feasible way toward concerted global action.

Myth #2: Cutting carbon pollution would hurt America’s economy.

Reality: Fighting climate change is critical to America’s prosperity. Drought is already wreaking havoc among U.S. farmers and ranchers. In decades to come, climate change-driven extreme weather and sea-level rise will threaten businesses, key infrastructure and public health around the country. That’s why America’s Clean Air Cities are urging federal action. At the same time, the cost of emissions reduction is likely much lower than anticipated: Reductions in other dangerous air pollutants over the past 40 years shows that regulation tends to spur innovation and technological advancement, reducing the cost of pollution controls.

Myth #3: Natural gas and fracking will save us.

Reality: Natural gas and fracking pose huge threats to our climate. First, there’s growing evidence that natural gas operations leak methane – an incredibly potent greenhouse gas – at very high rates. Because of these leaks, some experts conclude that uncontrolled shale gas fracking actually has a greater climate-change effect than coal over the whole production life cycle. Fracking also poses huge additional risks to air, water, wildlife and communities. Second, fracking is also being used to develop vast new reserves of shale oil.

Pushing China to adopt this destructive technology, as Richard Muller has advocated, would be like pouring rocket fuel on a forest fire. We need to transition to truly clean and renewable energy sources, not open up new fossil fuel deposits with damaging new drilling techniques.

Myth #4: Polar bears and other endangered animals aren’t really that threatened by climate change.

Reality: A large body of scientific evidence shows that global warming threatens polar bears, who depend on Arctic sea ice for hunting and all of their essential behaviors. The thickness and extent of the Arctic’s summer sea ice have declined dramatically over the past 30 years, and this year’s levels are currently tracking below record lows.

Based on evidence including declining population numbers, declining cub survival, and the drowning and starvation of individual bears, the government placed the polar bear on the threatened species list. Claims that polar bear numbers are actually rising are false: At least eight of the world’s 19 polar bear subpopulations are declining and just one is demonstrably increasing (due to the curtailment of severe overhunting levels), according to a 2009 report by the IUCN Polar Bear Specialist Group. Experts say that more than two-thirds of the world’s polar bears could be gone in less than 40 years.

Many other wildlife species are imperiled by climate change, posing a threat to our planet’s web of life.

Myth #5: A new law is the only way to meaningfully reduce U.S. emissions.

Reality: We already have the Clean Air Act, a potent weapon against greenhouse gas pollution. The Clean Air Act has reduced harmful air pollution for four decades. Courts have repeatedly upheld efforts to apply the Clean Air Act to greenhouse gases, but the Environmental Protection Agency has been too slow and timid in using the law to control carbon pollution. Full use of all of the Clean Air Act’s successful pollution-reduction programs offers our best hope for quick reductions in greenhouse gas emissions.

To head off the worst effects of climate change, we need to reduce atmospheric carbon dioxide levels to no more than 350 parts per million. The United States can’t delay any longer. For the sake of our planet and our future, we need to get moving in the fight against climate change.