Outlining a new climate change plan on a warm day in Washington, President Obama said Tuesday his State Department should not sign off on the Keystone XL oil pipeline if it increases greenhouse gas emissions.
"Our national interest will be served only if this project does not significantly exacerbate the problem of carbon pollution," Obama said during a major address on global warming at Georgetown University.
Keystone is not part of the climate change plan that includes new rules to restrict what Obama called "the limitless dumping" of carbon pollution from power plants, as well as the promotion of renewable energy sources and new energy-efficiency standards.
As part of his "climate action plan," Obama said he would direct agencies to help brace the nation for existing effects of climate change, including hotter temperatures and stronger storms. The president also pledged to seek new global agreements on climate change.
Warning that climate change threatens future generations, Obama told his college audience that "the question is not whether we need to act -- the overwhelming judgment of science, of chemistry and physics and millions of measurements, has put all that to rest."
He added: "The question now is whether we will have the courage to act before it's too late."
In discussing efforts to reduce carbon pollution, Obama said he would direct the Interior Department to permit new wind, solar and other renewable energy projects on public lands, enough to power more than 6 million homes by 2020.
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Almost all of the president's plan involves executive actions that do not require congressional approval. Obama would have a difficult time getting climate change legislation through Congress, given a U.S. House run by Republicans and a Senate in which the GOP has enough members to mount effective filibusters.
Republicans and members of the energy industry criticized Obama's climate change plan, saying it will lead to higher utility bills and less development of reliable energy.
These policies "will shutter power plants, destroy good-paying American jobs, and raise electricity bills for families that can scarcely afford it," said House Speaker John Boehner, R-Ohio.
Senate Minority Leader Mitch McConnell, R-Ky., said Obama's plan is a "war on coal" that translates to a "war on jobs."
Said McConnell: "It's tantamount to kicking the ladder out from beneath the feet of many Americans struggling in today's economy."
Congressional Republicans are also major backers of the Keystone oil pipeline, saying it will create jobs and increase the nation's energy supply.
The project is currently being reviewed by the State Department because it crosses the U.S.-Canadian border.
While Obama and aides said the State Department is making an independent judgment, Obama told the crowd at Georgetown that "the net effects of the pipeline's impact on our climate will be absolutely critical to determining whether this project is allowed to go forward."
Boehner spokesman Brendan Buck cited studies showing that the pipeline would not affect oil development in the Canadian tar sands, and therefore would have little environmental effect.
"The standard the president set today should lead to speedy approval of the Keystone pipeline," Buck said.
Obama referenced the politics of climate change during his remarks. While pledged to work with any willing Republicans, Obama repeatedly criticized GOP members for ignoring or disputing the science behind climate change.
"We don't have time for a meeting of the Flat Earth Society," Obama said at one point.
Obama also disputed that Republican contention that environmental and climate regulations hurt the economy, saying they can actually encourage growth and innovation.
Environmental groups rallied around Obama's plan, calling climate change a major problem that needs to be addressed now.
"Americans are already dealing with worse droughts, wildfires and coastal floods, and the practical realities of climate change are forcing political leaders to make this a priority," saidAlden Meyer, strategy and policy director at the Union of Concerned Scientists.
Meyer said that Obama "has a little more than three years to cement a lasting legacy on climate change, and he'll need every last second."
According to a White House blueprint of the climate plan, Obama will direct the Environmental Protection Agency to work with states, industry and other stakeholders to establish new carbon pollution standards for new and existing plants.
He will also require federal agencies to help state and local governments with existing problems caused by climate change, particularly the potential for major storm damage. Thatincludes development of what Obama called "smarter, more resilient" infrastructure.
As part of an international approach to climate change, Obama called for an end to U.S. government support for public financing of new coal-fired plants overseas. Obama said he would make exceptions if "they deploy carbon capture technologies, or there's no other viable way for the poorest countries to generate electricity."
Obama delivered his Georgetown climate address outside in 90 degree weather, and occasionally had to talk over the roar of airplanes.
Said Obama: "My first announcement today is, you should all take off your jackets."