The U.S. Environmental Protection Agency proposed a national system for reporting carbon dioxide and other greenhouse gas emissions by major emitters Tuesday.

The registry, which was originally proposed in a 2007 energy bill and is funded in U.S. President Barack Obama's 2010 Budget outline, would lay the foundation for regulation of CO2 and other gases thought to contribute to global warming.

"Our efforts to confront climate change must be guided by the best possible information," said EPA Administrator Lisa Jackson in a statement. "Through this new reporting, we will have comprehensive and accurate data about the production of greenhouse gases."

Jackson called the registry a "critical step toward helping us better protect our health and environment."

Obama's energy and climate czar, Carol Browner, who is widely believed to be directing the president's global warming agenda, has told Dow Jones Newswires that the EPA would issue a finding that carbon dioxide was a danger to the public, and that endangerment document would trigger regulation.

"EPA...will make an endangerment finding," Browner said in an interview late last month. A White House aide said later Tuesday that the energy czar wouldn't be interfering in the scientific process the EPA is conducting to make that endangerment determination.

Business groups such as the U.S. Chamber of Commerce and the National Association of Manufacturers warn that if the EPA moves forward on regulation of CO2 under the Clean Air Act as proposed - and which the registry prepares for - it could force the entire economy to a grinding halt.

Some groups say that the Securities Exchange Commission should now require companies to disclose to investors the liability that carbon dioxide regulation represents to their earnings - as the agency does with lawsuits or other factors that could have a substantial impact on firms' bottom lines - and a registry strengthens their argument.

"The SEC needs to protect investors from the risks companies face from climate change, whether from direct physical impacts or new regulations," said Mindy Lubber, Director of the Investor Network on Climate Risk, a group of 77 institutional investors managing approximately $7 trillion in assets. "Shareholders deserve to know if their portfolio companies are well positioned to manage climate risks or whether they face potential exposure," she said.

For example, utilities such as Duke Energy Corp. (DUK) or Southern Co. (SO) and oil majors such as Exxon Mobil Corp. (XOM) or Chevron Corp. (CVX) that know their approximate carbon dioxide emissions at their coal and refining plants could give the market guidance based on several different estimates on the cost of emitting carbon dioxide.

The EPA said around 13,000 facilities, accounting for about 85% to 90% of greenhouse gases emitted in the country, would be covered under the registry proposal.

In correspondence to Senators viewed by Dow Jones Newswires, Jackson said that the Clean Air Act, "when applied carefully and sensibly, (can) be an appropriate mechanism for regulating some sources of greenhouse gases."

She also said the Act gives her agency discretion to regulate emissions "in a way that does not necessitate direct regulation of all emission sources regardless of their size."

But legal analysts that have been battling environmental challenges to refineries and power plants say that the EPA's endangerment finding and greenhouse gas regulations would likely give many groups the legal foundation to challenge nearly any emitting source, such as schools, hospitals, and lawnmowers.

The EPA said the new reporting requirements would apply to suppliers of fossil fuel and industrial chemicals, manufacturers of motor vehicles and engines, as well as large direct emitters of greenhouse gases with emissions equal to or greater than a threshold of 25,000 metric tons a year, which is roughly equivalent to the annual greenhouse gas emissions from just over 4,500 passenger vehicles.

The vast majority of small businesses would not be required to report their emissions because their emissions fall well below the threshold, the agency said.

The direct emission sources covered under the reporting requirement would include energy intensive sectors such as cement production, iron and steel production, and electricity generation, and other energy-intensive operations.

"EPA may find it more difficult than it believes to limit greenhouse gas regulation under the Clean Air Act to only the biggest emitters," said Peter Glaser, a partner at the lawfirm Troutman Sanders who represents utilities. Glaser said environmental organizations have told EPA that once the agency starts down the path of regulating carbon dioxide under the Clean Air Act, it will be under a mandatory legal duty to implement regulations that will impose requirements on a multitude of small and large sources in all sectors of the economy.

Businesses would have to report to the EPA in 2011 for the calendar year 2010, except for vehicle and engine manufacturers, which would begin reporting for model year 2011. The EPA said it expected it would cost industry around $160 million in the first year to comply with the reporting requirements and around $127 million in subsequent years.

The president said he would prefer Congress to pass legislation that would cap greenhouse gas emissions and create a market to trade the right to pollute. But political analysts say the administration is using the threat of regulation of CO2 through the Clean Air Act - a law that some believe is too blunt an instrument for regulation of a gas that would impact the entire economy - to encourage reluctant lawmakers on the Hill to pass its climate change agenda.

A registry would provide the data for both types of regulation - a Congressionally created law or EPA rules.

Obama's 2010 budget proposed increasing the agency's funding by $19 million to pay for the new registration. He also accounted for the government collecting around $646 billion in "climate revenues" over the next decade, starting in 2012.

-By Ian Talley, Dow Jones Newswires; (202) 862 9285; ian.talley@dowjones.com;