When the founder of the Whole Earth Catalog embraces nuclear power, genetically engineered crops, and geoengineering schemes to cool the planet, you know things have changed in the environmental movement. In an interview with Yale Environment 360, Stewart Brand explains how the passage of four decades — and the advent of global warming — have shifted his thinking about what it means to be green.

The Copenhagen summit turned out to be little more than a charade, as the major nations refused to make firm commitments or even engage in an honest discussion of the consequences of failing to act.

As the world weighs how to deal with warming, the idea of human manipulation of climate systems is gaining attention. Yet beyond the environmental and technical questions looms a more practical issue: How could governments really commit to supervising geoengineering schemes for centuries?

Governments from the developed world will never come up with enough money to help poorer nations adapt to global warming and implement renewable energy technologies. The solution may lie in using a modest allocation of government funds to spur private sector investment in green energy projects in Africa, Asia, and Latin America.

As the UN conference enters its second and decisive week, the calls for strong global action to deal with climate change do not appear to be penetrating inside Copenhagen’s Bella Center.

Hampered by a slow-moving Congress, the Obama administration is offering only modest greenhouse gas reduction targets at the Copenhagen conference. But limited federal action does not mean the U.S. is standing still: More than half of the 50 states are already taking steps to reduce emissions on their own.

As wild fish stocks continue to dwindle, aquaculture is becoming an increasingly important source of protein worldwide. Now, a growing number of entrepreneurs are raising fish in large pens in the open ocean, hoping to avoid the many environmental problems of coastal fish farms.

Twelve years ago in Kyoto, the world was poised to act on a climate treaty but looked for a clear signal from the United States. Now, with the Copenhagen talks set to begin, the outcome once again hinges on what the U.S. is prepared to do.

Long a ubiquitous part of modern life, plastics are now in everything from diapers to water bottles to cell phones. But given the proven health threats of some plastics — as well as the enormous environmental costs — the time has come for the U.S. to pass a comprehensive plastics control law.

The solar power boom in Germany, Spain, and parts of the United States has been fueled by government subsidies. But now some U.S. states — led by New Jersey, of all places — are pioneering a different approach: issuing tradable credits that can be sold on the open market. So far, the results have been promising.

Over the last century, the intensive use of chemical fertilizers has saturated the Earth’s soils and waters with nitrogen. Now scientists are warning that we must move quickly to revolutionize agricultural systems and greatly reduce the amount of nitrogen we put into the planet's ecosystems.

With skepticism growing about the chances of reaching a climate agreement next month in Copenhagen, Rajendra Pachauri, chairman of the Intergovernmental Panel on Climate Change, says he is “cautiously optimistic” that a treaty can still be signed. But in an interview with Yale Environment 360, Pachauri says the global community may have to move ahead without any commitment from the United States.

As the world warms, how different societies fare in dealing with rising seas and changing weather patterns will have as much to do with political, social, and economic factors as with a changing climate.

Although it is a heavily urbanized nation, fully two-thirds of Japan remains woodlands. Yet many of the forests are timber plantations inhospitable to wildlife, especially black bears, which are struggling to survive in one of the most densely populated countries on Earth.

Green rankings in the U.S. don’t tell the full story about the places where the human footprint is lightest. If you really want the best environmental model, you need to look at the nation’s biggest — and greenest — metropolis: New York City.

Interfering with the Earth’s climate system to counteract global warming is a controversial concept. But in an interview with Yale Environment 360, climate scientist Ken Caldeira talks about why he believes the world needs to better understand which geoengineering schemes might work and which are fantasy — or worse.

Of the various geoengineering schemes being proposed to cool an overheated planet, one approach — extracting carbon dioxide from the atmosphere using “artificial trees” — may have the most potential. But both questions and big hurdles remain before this emerging technology could be widely deployed.

The average American produces three times the amount of CO2 emissions as a person in France. A U.S. journalist now living in Europe explains how she learned to love her clothesline and sweating in summer.

By the end of the century, New York’s climate could resemble that of present-day Raleigh, North Carolina and its harbor could easily rise by two feet or more. Faced with this prospect, the city is among the first urban centers to begin changing the way it builds its infrastructure — and the way it thinks about its future.

The U.S. can build all the wind turbines and solar arrays it wants, but until it does something about improving its outmoded electricity grid, renewable energy will never reach its potential. What we need is a new electricity transmission system, with the costs shared by all.