The debate over global warming typically features environmentalists and big business types hollering at each other through a fog of scientific argument and economic cant.
Lately, however, the battle lines have blurred as more companies cross over to acknowledge that "greenhouse gases" such as carbon dioxide could well cause climate change. Whether the argument and cant have lessened is another matter.
A national ad campaign this week features 13 major corporations warning that "Climate change is serious business - for all of us." Among the companies (whose combined revenues are more than $340 billion) are Boeing, British Petroleum, Lockheed Martin, Maytag, United Technologies, and 3M.
"Instead of choosing between business and the environment, we want to draw on the ingenuity and expertise of all sectors to both address the climate change problem and sustain economic growth," says Eileen Claussen, executive director of the Pew Center on Global Climate Change, which is sponsoring the TV and newspaper ads.
But even before this latest development, the ideological wall had begun to crack in what has become one of the most profound and controversial environmental issues in history.
Last month, Shell Oil Co. broke ranks with most petroleum producers in announcing that it would leave the Global Climate Coalition, an industry trade group that lobbies against government-imposed limits on carbon emissions.
"I find myself increasingly persuaded that a climate effect may be occurring," said Mark Moody-Stuart of the Royal Dutch/Shell Group, the world's largest oil company. Mr. Moody-Stuart is slated to become Shell's CEO in July. Speaking to energy industry officials in February, the Shell official warned against "a tobacco-industry-like reluctance to admit the possibility of any problem."
Late last year, Sun Oil Co. (the Pennsylvania company that markets Sunoco gasoline) acknowledged that "there is sufficient scientific concern about man-made climate impacts to justify initiation of prudent mitigation measures now."
In a letter to President Clinton just before the December Kyoto summit on climate change, Sun chief executive Robert Campbell said the administration was "right on the target" in its proposal to limit carbon emissions - a statement that put him at considerable odds with most of his colleagues in the oil industry.
Last year, British Petroleum chief John Browne said, "It would be unwise and potentially dangerous to ignore the mounting concern" over global warming. "Climate change is a long-term problem, and what matters is that we begin to take precautionary steps," said BP's CEO.
If anything, this movement by some major corporations to acknowledge the likelihood of global warming has ratcheted up the effort to sway public opinion.
It was reported recently that industry opponents of a treaty to reverse global warming are designing a $5 million, two-year plan to push their point of view in the media. This plan, put together by the American Petroleum Institute, includes efforts to "identify, recruit, and train a team of five independent scientists to participate in media outreach," according to an internal memo leaked to the press by the National Environmental Trust, an advocacy organization in Washington that accused the industry group of pushing "junk science" on an unsuspecting public.
Political conspiracy theorists note the incestuous nature of the attempts to manipulate public opinion - by environmental groups as well as by industry.
The National Environmental Trust, for example, was set up several years ago by the Pew Charitable Trusts. One of the largest private philanthropies in the county, the Pew trusts also created the Pew Center on Global Climate Change - the new organization behind this week's ads on global warming featuring the 13 major corporations.
Eileen Claussen, the new Pew organization's executive director, was assistant secretary of state in the Clinton administration specializing in global-warming and other environmental issues.
And as an ironic historical twist, the Pew Charitable Trusts - now bankrolling much of the environmental effort to fight global warming - were established between 1948 and 1979 by the children of the founder of Sun Oil Co.
Some see the ad campaign starting this week as a front for the White House push to fight global warming; others charge that the effort by oil companies and other industries to recruit "independent scientists" is merely a public-relations ploy to protect polluting industries.
While not all scientists agree that climate change tied to human activities is happening, most experts support the view that change is possible - if not likely.
Writing in a recent issue of Nature magazine, three climatologists reported that this century has been the warmest of the last six. The warmest years were 1990, 1995, and 1997.