WASHINGTON -- Climate change, it seems, is no longer a dirty phrase for Democrats to disavow.

President Barack Obama promised in his second inaugural address to respond to climate change, casting it as a moral obligation and warning that failing to take action "would betray our children and future generations." It’s not just a responsibility to his fellow Americans, Obama said Monday, but to "all posterity."

Persuading Americans that they should care about climate change _ or have a duty to do so _ is one thing. Actually doing something about the emissions that contribute to rising sea levels, sooty skies and melting Arctic sea ice is a far more complex task. Despite Obama’s pledges Monday, the White House was scant with details this week, saying only that it’s pursuing action under the existing regulatory framework.

Given that sweeping legislation to cap greenhouse gas emissions not only failed in his first administration, but also fell apart in a way that may have damaged the fortunes of future climate-related legislation, the White House has challenging work ahead. It must negotiate a polarized Congress, regional energy interests and pressure from big polluters and the influential energy sector.

The industry is bracing for a fight. Some groups, such as the National Association of Manufacturers, have challenged the Environmental Protection Agency’s authority to regulate greenhouse gases under the Clean Air Act.

They’ll continue to argue that regulation of greenhouse gases should come from Congress, not the executive branch, said Ross Eisenberg, the vice president of energy and resources policy for the association. International emissions and the economic consequences of U.S. regulatory decisions need to be factored in, too, he said.

"If you put constraints on one economy, and other economies you’re competing with don’t have it, you’re constraining growth and putting an additional cost on the manufacturing process that your competitors don’t have," he said.

Congress has shown that it remains divided over what environmentalists say is one key indicator of how the second Obama administration will approach emissions. A majority of senators urged the president this week to approve the Keystone XL pipeline, which would bring oil to the United States from the Canadian tar sands. The administration has twice delayed a decision, which is pending environmental approval at the State Department. Sen. John Kerry, D-Mass., gave no indication Thursday in his confirmation hearing to become the next secretary of state how he’d move on the decision, but he said he’d make sure that climate change issues are taken into consideration.

Meanwhile, the governor of Nebraska signed off this week on the pipeline’s path through the state.

Yet those who favor action on climate change said they were hopeful, and they’ve been drawing up plans for the White House that they think match the rhetoric of the inaugural address. Obama’s re-election was the first step, said Bob Deans, a spokesman for the Natural Resources Defense Council. The next step, he and other environmentalists said, is for the president to act on his pledge.

"In November, the country went with the guy who said it’s a threat," Deans said. "Is that a mandate? I don’t know. But without question it’s a historic opportunity. And on Monday, the president showed he’s very serious about taking advantage of that opportunity."

The biggest step, major legislation that would have capped emissions and set up markets to trade pollution credits, failed in 2010 and is unlikely to be resurrected.

But there’s plenty more the administration could do without legislation, said the Clean Air Task Force, a nonprofit that’s dedicated to reducing air pollution. The task force wrote a letter to the president earlier this month saying the administration could work to curb methane emissions from the pipeline and production system, even as domestic oil and gas production booms.

They’d also like to see more attention to coal. Given recent projections that show the use of coal surging worldwide, even as older, inefficient plants close in the United States, the Clean Air Task Force would like some attention paid to developing the technology to capture carbon emissions from coal-fired plants.

Such technology also could be applied to natural gas, which in the United States is rapidly replacing coal. Although natural gas-fired power plants still produce greenhouse gas emissions, it’s at about half the rate of coal plants.

"To get serious about climate means getting serious about solving coal emissions, because they won’t disappear or be replaced," said John Thompson, the head of the Clean Air Task Force’s fossil transition team. "We need carbon capture in the United States, not just for coal, but for gas as well. When it comes to pathways for climate change, all paths have to lead to addressing coal and gas through carbon capture technology."

The most likely path in coming months, though, may be through the EPA’s regulatory authority. The administration is finalizing emission rules for new power plants; environmental groups such as the Natural Resources Defense Council are calling for rules that would target existing plants.

White House Press Secretary Jay Carney wouldn’t say this week whether the administration would move to regulate existing plants. The EPA administrator, Lisa Jackson, is stepping down, and the president hasn’t yet named a new leader for an agency that Republicans often target as overbearing.

"I can certainly confirm that the president intends to continue progress on the new national standard for harmful carbon pollution from new power plants, and to implement that standard," Carney said. "I can’t comment on any specific future actions that he might take, except that he has demonstrated in his record during his first term that we can, together, take action that is not only helpful to our environment, in that it addresses the issue of climate change."

Obama himself warned in his inaugural address that the path toward sustainable energy sources would be "long and sometimes difficult." His administration hasn’t tipped its hand when it comes to the Keystone pipeline, which, if approved, environmentalists would consider a failure to rein in future greenhouse gas emissions.

The pipeline’s rejection is one of the key goals of the Sierra Club, which said this week that for the first time in its 120-year history it would pursue a strategy of civil disobedience to oppose the pipeline. Obama’s mention of acts of civil disobedience in Selma, Ala., Seneca Falls, N.Y., and Manhattan’s Stonewall inspired their action, said the club’s executive director, Michael Brune.

"We want him to follow up that speech by exercising his full authority as an executive," Brune said, "but also his full abilities as chief persuader."

• Read more articles by Erika Bolstad

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