Geoengineering involves directly manipulating the climate to lower the temperature.

With political action on curbing greenhouse gases stalled in the U.S., a bipartisan panel of scientists, former government officials and national security experts is recommending that the government begin researching a radical fix: directly manipulating the Earth's climate to lower the temperature.

Members said they hoped that such extreme engineering techniques, which include scattering particles in the air to mimic the cooling effect of volcanoes or stationing orbiting mirrors in space to reflect sunlight, would never be needed. But in its report, to be released Tuesday, the panel said it is time to begin researching and testing such ideas in case “the climate system reaches a ‘tipping point' and swift remedial action is required.”

The 18-member panel was convened by the Bipartisan Policy Center, a research organization based in Washington founded by four senators — Democrats and Republicans — to offer policy advice to the government. In interviews, some of the panel members said they hoped that the mere discussion of such drastic steps would jolt the public and policymakers into meaningful action in reducing greenhouse gas emissions, which they called the highest priority.

The idea of engineering the planet is “fundamentally shocking,” David Keith, an energy expert at Harvard and the University of Calgary and a member of the panel, said. “It should be shocking.”

In fact, it is an idea that many environmental groups have rejected as misguided and potentially dangerous. Jane Long, an associate director of the Lawrence Livermore National Laboratory and the panel's co-chairwoman, said that by spewing greenhouse gases into the atmosphere, human activity was already engaged in climate modification.

“We are doing it accidentally, but the Earth doesn't know that,” she said, adding, “Going forward in ignorance is not an option.”

The panel, the Task Force on Climate Remediation Research, suggests that the White House Office of Science and Technology Policy begin coordinating research and estimates that a valuable effort could begin with a few million dollars in financing over the next few years.

One reason that the United States should embrace such research, the report suggests, is the threat of unilateral action by another country. Members say research is already under way in Britain, Germany and possibly other countries, as well as in the private sector.

“A conversation about this is going to go on with us or without us,” said David Goldston, a panel member who directs government affairs at the Natural Resources Defense Council and is a former chief of staff of the House Committee on Science. “We have to understand what is at stake.”

It is impossible to predict how much impact the report will have. But given the panelists' varied political and professional backgrounds, they seem likely to achieve one major goal: starting a broader conversation on the issue. Some climate experts have been working on it for years, but they have largely kept their discussions to themselves, saying they feared giving the impression that there might be quick fixes for climate change.

''Climate adaptation went through the same period of concern,” Mr. Goldston said, referring to the onetime reluctance of some researchers to discuss ways in which people, plants and animals might adjust to climate change. Now, he said, similar reluctance to discuss geoengineering is giving way, at least in part because “it's possible we may have to do this no matter what.”

Although the techniques, which fall into two broad groups, are more widely known as geoengineering, the panel prefers “climate remediation.”

The first is carbon dioxide removal, in which the gas is absorbed by plants, trapped and stored underground or otherwise removed from the atmosphere. The methods are “generally uncontroversial and don't introduce new global risks,” said Ken Caldeira, a climate expert at Stanford University and a panel member. “It's mostly a question of how much do these things cost.”

Controversy arises more with the second group of techniques, solar radiation management, which involves increasing the amount of solar energy that bounces back into space before it can be absorbed by the Earth. They include seeding the atmosphere with reflective particles, launching giant mirrors above the earth or spewing ocean water into the air to form clouds. These techniques are thought to pose a risk of upsetting earth's natural rhythms. With them, Mr. Caldeira said, “the real question is what are the unknown unknowns: Are you creating more risk than you are alleviating?”

At the influential blog Climate Progress, Joe Romm, a fellow at the Center for American Progress, has made a similar point, likening geo-engineering to a dangerous course of chemotherapy and radiation to treat a condition curable through diet and exercise or, in this case, emissions reduction. The panel rejected any immediate application of climate remediation techniques, saying too little is known about them.

— New York Times News Service

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