With a new study showing 97 percent of scientific papers on climate change since 1991 agree that fossil fuels are largely responsible, the doubters need to stand aside so public-policy initiatives to protect the Earth can proceed.

There is as much heat-trapping carbon dioxide in the atmosphere now as there was in the Pliocene Age, three million years ago, when oceans were 70 feet higher and temperatures warmer. Carbon dioxide levels are 41 percent higher now than during the Industrial Revolution - and climbing.

The doubters, though, have done a lot of damage. By insisting climate change isn't occurring, or not caused by human use of fossil fuels and industrialization, they have reduced investments in alternative energy and slowed the progress of policies such as demanding higher vehicle gas mileage and imposing stronger emission standards on coal plants.

Their ranting has so muddied the water that less than half of the American public knows that most scientists agree that fossil fuels cause climate change, according to a Pew Research study. They have spewed so much misinformation that politicians, including President Obama, appear afraid to call them out.

Research by physics professor John Cook and his team of Australian and North American scholars who maintain the Skeptical Science website shows there has been scientific consensus on climate change for 20 years. But fossil fuel barons such as the Koch brothers and energy companies like Exxon have funded contradicting research to block tougher environmental regulations.

The United States is second only to China in emitting carbon. Air pollution is so bad in China that smog has shut down the Beijing airport several times. Parents in China's cities seek schools with air purifiers because so many of their children have respiratory illnesses. The country's explosion in manufacturing jobs may have made China an economic power, but its polluting industries are making the nation sick.

Meanwhile, superstorms in the United States have become more common, and the recovery in coastal communities more expensive. Extreme weather in the Midwest has meant deep droughts in the nation's breadbasket.

This country and China have resisted global efforts to reduce carbon emissions. Their intransigence costs more in the long run. Just consider how much is spent on related health problems, not to mention recovery efforts after storms. The debate about what causes climate change is over. It's time to do something about it.