At the same time, shareholders increasingly are filing resolutions seeking such disclosure, as well as a broader range of actions, including sustainability reporting and planning for carbon footprint reduction.

"It's about providing comprehensive info that's financial in nature that relates to the energy and environmental footprint," said Mindy Lubber during a March 4 media release conference call. Lubber is president of the corporate social responsibility nonprofit Ceres and directs Ceres' Investor Network on Climate Risk, a network of 80 institutional investors with $8 trillion of collective assets.

The SEC, in its January interpretive guidance, aimed to provide clarity of existing rules requiring companies to disclose risks related to climate change.

The commission highlighted areas such as the impact of legislation and regulation, the impact of international accords and the indirect consequences of regulation or business trends, as well as the direct physical impacts of climate change.

"We are not opining on whether the world's climate is changing, at what pace it might be changing or due to what causes. Nothing that the commission does today should be construed as weighing in on those topics," said SEC Chairman Mary Schapiro at the time.

The guidance simply would help ensure that disclosure rules are consistently applied, she said.

It might be difficult for companies to identify and predict climate change-related risks, said West Virginia University economics Professor Russell Sobel.

But, Sobel added, investors probably already have taken larger risks into account.

"For example, I'll bet that you could find that major hurdles in the cap-and-trade bill process -- when bills were introduced, made it out of committee, etc. -- already correlate with coal stock prices," he said.

Meanwhile, the number of climate change-related shareholder resolutions increased in the 2010 proxy season, according to Ceres and the Interfaith Center of Corporate Responsibility.

Major institutional investors working cooperatively with these organizations -- pension funds, labor organizations, faith-based groups and others -- filed 95 climate change resolutions this year, a 40 percent increase over the 68 filed during the 2009 proxy season, Lubber said.

Resolutions ask Exxon Mobil Corp. and ConocoPhillips Co., for example, to report on regulatory, legal and reputational risks, as well as environmental impacts, from their Canadian oil sands operations. Oil sands production has a larger carbon footprint than traditional oil production, and both companies' operations face regulatory and legal challenges both in the U.S. and Canada.

Other shareholder resolutions seek disclosure from electric utilities, including Southern Company, and coal producers, such as CONSOL Energy and Massey Energy Co., on their plans for adopting greenhouse gas reduction goals in anticipation of expected carbon-reduction regulations.

Scott Depot-based International Coal Group shareholders have filed a resolution asking the company to report its response to rising pressure to reduce CO2 emissions from products.

Twenty-eight of the resolutions have been successfully negotiated and withdrawn, according to an INCR database.

Among those, shareholders of Abingdon, Va.-based coal producer Alpha Natural Resources negotiated a resolution similar to the one filed with ICG.

Most of the companies in the INCR database of shareholder resolutions hold their annual shareholder meetings in April and May.