AUGUSTA – The recent cold snap notwithstanding, Attorney General Steven Rowe believes global warming is an immediate threat to Maine’s economy and to the health of its people.

Rowe announced Thursday that he and the attorneys general from Massachusetts and Connecticut are planning to sue U.S. Environmental Protection Agency Administrator Christie Whitman to force the Bush administration to take action on climate change by regulating carbon dioxide emissions.

“Today’s action is not taken lightly,” said Tom Reilly, Massachusetts attorney general, during a joint telephone conference Thursday for the media. “This is serious business. What’s happening today with global warming is a direct threat to our environment, to our health, and to our national security,” he said.

A lawsuit could be filed within 60 days.

Scientists have long believed that carbon dioxide, created by burning fossil fuels in automobiles, factories and power plants, is a major component of greenhouse gases in the atmosphere. The gaseous blanket insulates the planet, trapping heat and causing the phenomenon known as global warming.

In May 2002, the EPA released a report to the United Nations stating that carbon dioxide is the major factor in human-caused climate change.

“The fact that carbon dioxide causes global climate change is no longer in dispute,” Rowe said Thursday.

The emission of carbon dioxide into the atmosphere is expected to increase 43 percent by 2020, the report said. Scientists’ predictions are dire: An average temperature increase of 5 to 9 F and an average sea level jump of between 4 and 35 inches can be expected over the next century.

This level of change could result in outbreaks of insect-borne illnesses such as Lyme disease and West Nile virus. Lung disease and asthma could become more prevalent.

Rising sea levels could increase flooding and beach erosion. Changing weather patterns could result in storms of greater intensity.

Lakes could be clogged with algae blooms. Temperature-sensitive species, including Maine lobsters and moose, could disappear.

“It’s not just a luxury – it’s a matter of life and death,” said Connecticut Attorney General Richard Blumenthal.

The attorneys general contend Whitman has violated the Clean Air Act by not adding carbon dioxide to an official list of regulated pollutants, despite her agency’s knowledge of its harmful effects.

Other greenhouse gases, including ozone, carbon monoxide, nitrogen dioxide and sulfur dioxide, are already regulated, in addition to particulate matter and lead.

Eleven states, including all of New England, signed a July 2002 letter to President Bush, urging him to consider listing carbon dioxide.

Instead, the administration has supported a plan to require only voluntary reductions in carbon dioxide, and 10 to 15 years of study.

An EPA spokesperson could not be reached for comment Thursday.

Within 15 years, global warming will be a problem, the attorneys general said. Some researchers say impacts are evident now.

They cite sea levels worldwide that already have risen 4 to 8 inches since 1900, a decline in lobsters in Long Island Sound, and songbirds that have changed their migrations.

And in the EPA report, scientists say even if strong restrictions on greenhouse gases were implemented today, pollutants in the air would continue to affect climate for at least a century.

“We will all suffer the consequences of this administration’s failure,” Blumenthal said. The president’s State of the Union address “revoked all hope,” he said.

Hopes for the lawsuit are high, however. In 1976, the Natural Resources Defense Council won a similar case, forcing the government to add lead to its list of air pollutants.

The Sierra Club and the Conservation Law Foundation have announced support for the current initiative, and other environmental groups and states are expected to follow.

Maine is involved in a lawsuit brought by New England attorneys general against the Bush administration in early January because of the president’s stance on New Source Review, a partial revision of the Clean Air Act that exempts old power plants and factories from air regulations.

New Englanders are particularly concerned because much of the air pollution created in Midwestern industrial centers drifts eastward on prevailing air currents and settles along the Atlantic Ocean.