Here are some actions Obama can take, sans Congress:
Appointments. The president could be losing three strong advocates for action on climate change in his Cabinet: Energy Secretary Steven Chu is expected to resign, and the EPA administrator and the secretary of the Interior have already announced their departures. His choices for successors will say a lot about how committed the administration is to an aggressive climate-change agenda.
Sen. John Kerry, the Massachusetts Democrat who has been nominated to be secretary of State, pledged at his confirmation hearing last week to be a “passionate advocate” of using energy policy to solve climate change. The State Department leads U.S. negotiators on international agreements to address climate change, although any new commitments would need approval of the Senate. State is also charged with determining whether a permit for the proposed Keystone XL pipeline, which would carry oil from Canada's tar sands to U.S. refineries on the Gulf Coast, is in the national interest.
Regulation and enforcement. The biggest—and most widely expected—executive action is the EPA’s release of final rules limiting carbon dioxide emissions from new power plants. Additional action may be taken to address methane emissions from the oil and gas industry, something the Clean Air Task Force urged Obama to tackle in an open letter to the president earlier this month.
EPA will play the biggest, but not the only, role in implementing Obama’s second-term vision for climate change. A host of other departments have climate-related authority: Interior will be involved in discussions over oil drilling, fracking, and offshore wind turbines. Energy can set efficiency standards for appliances and buildings. The Agriculture Department is involved in implementing mandates for biofuels, such as corn-based ethanol. The Commerce Department oversees the National Oceanic and Atmospheric Administration, which interprets and explains climate science. The Transportation Department has a say in fuel-economy standards.
Public pronouncements. Next month’s State of the Union address will bring more clarity to just how Obama plans to tackle climate change. The Senate confirmation hearings for key Cabinet posts should also shed some light on just how rocky Obama's path forward will be.