With or without federal regulations, companies in the United States and elsewhere are serious about the threat of global warming and are taking steps to curb or at least minimize its effects. While this is encouraging, it would be better if the U.S. government would step in with substantial rules to ensure a unified approach to greenhouse gas reductions.

Even businesses are advocating this approach, according to a cover story in the current issue of Business Week. The lengthy article chronicles that many people – from scientists to policy makers to corporate executives – believe that global warming is the biggest threat facing the planet. There is plenty of evidence that the climate is changing: rising temperatures, decreased ocean salinity from the influx of fresh water from melting glaciers, animal species moving to cooler climates. More importantly, there is evidence that companies are increasingly aware of the threat and changing their practices and processes to avert it.

James Connaughton, chairman of the White House Council on Environmental Quality, says the companies took action because of “cajoling” from the Bush administration. During a visit here yesterday, Mr. Connaughton noted that President Bush has set a national goal of reducing American greenhouse gas intensity 18 percent by 2012.

This is not the same as reducing greenhouse gas emissions by 18 percent, because intensity measure output based on gross domestic product, not on its own.

Mr. Connaughton said the administration was concerned that tougher regulations would impel companies to move abroad, where environmental regulations were less stringent. Britain, on the other hand, has pledged to reduce its emissions 60 percent by 2050. Domestically, California has proposed a 30-percent reduction in auto emissions by 2015. Maine has committed to reduce greenhouse gases to 1990 levels by 2010 and state government has already cuts its emissions by 4 percent.

By contrast, DuPont has cut its greenhouse gas emissions by 65 percent since 1990. Alcoa, the world’s largest aluminum company, aims to cut emissions 25 percent by 2010. General Electric has acquired wind and solar power entities. General Motors is spending millions to develop hydrogen-powered cars that don’t emit carbon dioxide.

Such companies are not waiting for cajoling, but have realized that what is good for the environment is often good for the bottom line. BP reduced its emissions by 10 percent in three years and saved the company $650 million.

Still, the Bush administration has resisted attempts to regulate emissions of greenhouse gases such as carbon dioxide which act like a greenhouse roof, letting in sunlight but trapping heat around the Earth. “No nation will mortgage its growth and prosperity to cut greenhouse-gas emissions,” Energy Secretary Spencer Abraham told Business Week.

Companies in the United States and around the world, however, are finding that such a trade-off is unnecessary. So, one set of federal rules would be better than the hodge-podge of state and international regulations, which are springing up in the absence of action from Washington.