In recent months, climate change skeptics have ramped up their efforts in the media and Congress to misrepresent the scientific consensus on global warming. They have questioned the integrity of climate researchers and claimed that reducing carbon emissions would wreck our national economy. Such tactics are meant to sow confusion and lull the public into a dangerous complacency.
In response, scientists must communicate their research methods and findings more broadly and more effectively. More than 2,000 economists and scientists recently called on "our nation's leaders to swiftly establish and implement policies to bring about deep reductions in heat-trapping emissions." That is a step in the right direction.
But scientists do not have a bully pulpit. President Obama does -- and the public desperately needs him to use it.
The president clearly understands the urgency to act on global warming. Shortly after the election in November 2008, he said his administration would chart a course to reducing U.S. emissions of heat-trapping gases 80 percent by 2050 -- the amount that climate scientists say is necessary to avoid catastrophe. "The science is beyond dispute and the facts are clear," he stated. "Delay is no longer an option."
Since taking office, the president has spoken frequently about the role of clean energy technologies in creating millions of new jobs and revitalizing the economy. His fiscal stimulus bill put tens of billions of dollars into strategic investments in these technologies, and his administration has taken other important steps, including a rule that will make the new car and light truck fleet 40 percent more fuel efficient by 2016. He has brought members of Congress, business leaders, and others to the White House to build support for comprehensive climate and energy legislation.
These are all important steps and represent a complete reversal from the policies of the previous administration. An increased commitment to energy efficiency, renewable energy and other clean energy technologies is essential to U.S. leadership in the clean energy economy of the 21st century. But there is one issue on which the president can, and should, say much more: the strong scientific evidence on human-induced climate change and its impacts on the United States, and the rapidly closing window for action.
Last year, on behalf of the U.S. Global Change Research Program, an expert team of scientists summarized the science of climate change and the impacts of climate change on the United States, now and in the future, and called the evidence of a warming climate "unequivocal," primarily due to the use of fossil fuels - coal, oil, and gas - and the loss of forests. The report emphasized that "sizable early cuts in emissions would significantly reduce the pace and the overall amount of climate change. Earlier cuts in emissions would have a greater effect in reducing climate change than comparable reductions made later."
As the president travels around the country, he should alert citizens to these mounting costs of inaction. As temperatures rise, so do their consequences, and so does the importance of reducing emissions. Midwestern farmers could face more frequent days of extreme heat, heavier spring rains, and wider-ranging crop-damaging pests. California faces temperature increases that will affect agriculture, worsen the risk of large wildfires, and reduce the winter snowpack that is so important to year-round water supply.
The president should bring together scientists and others with relevant expertise for a White House summit on climate science, the urgency of action, and the opportunity for timely solutions. The headliners of this event should include the president and the government's own experts -- people like White House science adviser John Holdren, Energy Secretary Steven Chu, and NOAA Administrator Jane Lubchenco -- each of them superb scientists in their own right.
In addition, the president's secretaries of defense and homeland security should communicate to the public that climate change has the potential to produce serious threats to national security. It could endanger global water and food supplies and flood coasts with rising seas; these impacts, in turn, could trigger mass migrations and violent conflicts. The bottom line: Climate change is likely to exacerbate the conditions that foster violent extremism, with weakened and failed states being especially vulnerable.
President Obama just brokered a new treaty limiting nuclear weapons with Russia, moving another step toward his long-term goal of ridding the world of nuclear weapons. Now it is time for him to step up his efforts on another major threat to the future of the planet. The president should deliver a major speech on climate change to the American public, using all the props and charts he can muster to bring the message home. The public interest requires it.
The scientific community has long known that emissions from burning fossil fuels are changing Earth's climate. President Obama is uniquely qualified to cut through the fog created by misleading and manufactured controversies by telling the American public the truth. As he leads, our country will respond.
James J. McCarthy, the Alexander Agassiz professor of biological oceanography at Harvard University, is the immediate past president of the American Association for the Advancement of Science and chairman of the board of the Union of Concerned Scientists. Timothy E. Wirth, president of the United Nations Foundation, represented Colorado in the U.S. House and Senate from 1974 to 1992 and has served as undersecretary of state for global affairs.