Europe’s backpedaling last month on toughening its carbon trading system may have signaled the end of its leadership on climate change. Now, with a new administration and Congress, America appears ready to commit itself to tackling global warming.

Environmentalists from Bill McKibben and Paul Hawken, to Fred Krupp and Frances Beinecke offer President Obama their advice on the priorities he should set for the first 100 days of his administration.

In evaluating an economic recovery package, the new U.S. administration and Congress must weigh any proposed spending on highways or mass transit or wind-power transmission routes on the basis of clear criteria that would assess just how green the projects will be.

For four decades, American politicians have talked about ending U.S. dependence on foreign oil. But during the campaign and since his election victory, Barack Obama has made it clear that he finally intends to change the way America powers itself.

In the last eight years, vast areas of offshore Alaska have been opened to oil drilling. Now, a conservationist argues, the Obama administration must reverse the Bush-era policies if the state is to avoid irreparable harm to Arctic wildlife and to some of the most biologically productive waters on earth.

As he assumes the presidency, Barack Obama must make climate-change legislation and investment in green energy top priorities. And he must be ready to take bold — and politically unpopular — action to address global warming.

The next U.S. president should not wait for Congress to act on climate-change legislation. Instead, he should make use of the Clean Air Act to begin controlling greenhouse gas emissions and to implement a national cap-and-trade program.

Stavros Dimas, environmental commissioner for the European Union, says the global economic crisis is no reason to lose focus on efforts to fight climate change. In an interview with Yale Environment 360, he talked about the lessons of the EU's emissions trading system, and why the U.S. should not give away permits in a cap-and-trade system — it should get something for them.

Environmentalists had been looking to a new president and a new Congress to pass legislation dealing with global warming next year. But with tough economic times looming, the passage of a sweeping climate change bill now appears far less likely.

Despite the potential for abuse, the concept of paying others to compensate for our environmental sins can be a valuable tool in helping reduce carbon emissions. But the world can’t simply buy its way out of global warming.

Oil isn't America's only fuel addiction. Inefficient and environmentally damaging, the corn-ethanol boondoggle will nonetheless be hard to stop.

Congress has repeatedly failed to extend the tax credits for renewable energy, which expire at the end of this year. The gridlock is discouraging investment in renewables and jeopardizing major solar and wind projects throughout the country.

Texas billionaire T. Boone Pickens has always been one to think big. But his sweeping 10-year energy plan for America faces obstacles that may be insurmountable.

The crackdown on dissent surrounding the Beijing Olympics has been a reminder of China’s lingering authoritarianism. Yet for all our differences, the U.S. and China — the world’s two largest emitters of carbon dioxide — have no choice but to work together to tackle climate change.