Now in its seventh year, the EU’s carbon emissions trading system is the only international program designed to use market mechanisms to control CO2 emissions. But critics contend it has done little to slow the release of CO2 and argue that it should be significantly reformed — or scrapped.

While Brazil touts its efforts to slow destruction of the Amazon, another biodiverse region of the country is being cleared for large-scale farming. But unlike the heralded rainforest it borders, the loss of the cerrado and its rich tropical savanna so far has failed to attract much notice.

For three decades, Raoul du Toit has led the fight to protect black rhinos in Zimbabwe, a struggle that earned him a Goldman Environmental Prize this week. In an interview with Yale Environment 360, he talks about the challenge of saving this iconic African animal in the face of his country’s economic collapse and a new wave of poaching.

Norway and other nations have vowed to invest billions of dollars to help preserve Indonesia’s remaining tropical forests. But can foreign involvement stem the tide of graft and uncontrolled logging that has steadily decimated one of the world’s largest areas of rainforest?

To offset their own carbon emissions, European companies have been overpaying China to incinerate a powerful greenhouse gas known as hfc 23. And in a bizarre twist, those payments have spurred the manufacture of a harmful refrigerant that is being smuggled into the U.S. and used illegally.

The synthetic chemical, BPA — found in everything from plastic bottles to cash register receipts — is a potent, estrogen-mimicking compound. In an interview with Yale Environment 360, biologist Frederick vom Saal harshly criticizes U.S. corporations and government regulators for covering up — or ignoring — the many health risks of BPA.

In the past century, populations of wild tigers have plummeted from 100,000 to 3,500. Now the World Bank and conservationists have launched an eleventh-hour effort to save this great predator, focusing on reining in the black market for tiger parts and ending the destruction of tiger habitat.

With an aggressive campaign focused on advertising, lobbying, and political contributions, America’s coal industry has succeeded in beating back a challenge from environmentalists and clean-energy advocates. The dirty truth is that Big Coal is more powerful today than ever.

With large swaths of forest destroyed by wartime defoliants, and even larger areas lost to post-war logging, Vietnam has set an ambitious goal for regenerating its woodlands. But proponents of reintroducing native tree species face resistance from a timber industry that favors fast-growing exotics like acacia.

Ecuador's Yasuni National Park is one of the most biodiverse places on Earth and is home to remote Indian tribes. It also sits atop a billion barrels of oil. Now, Ecuador and the United Nations are forging an ambitious plan to walk away from drilling in the park in exchange for payments from the international community.

LEED certification has emerged as the green standard of approval for new buildings in the United States. But the criteria used for determining the ratings largely ignore factors relating to human health, particularly the use of potentially toxic building materials.

Large corporations, not small-scale farmers, are now the major forces behind the destruction of the world’s tropical forests. From the Amazon to Madagascar, activists have been directing their actions at these companies — so far with limited success.

For years, free-market fundamentalists opposed to government regulation have sought to create doubt in the public’s mind about the dangers of smoking, acid rain, and ozone depletion. Now they have turned those same tactics on the issue of global warming and on climate scientists, with significant success.

As global warming intensifies, demands for human manipulation of the climate system are likely to grow. But carrying out geoengineering plans could prove daunting, as conflicts erupt over the unintended regional consequences of climate intervention and over who is entitled to deploy climate-altering technologies.

In response to the widening disaster in the Gulf of Mexico, government officials have approved a plan to intercept the oil by building a 45-mile sand berm. But scientists fear the project is a costly boondoggle that will inflict further environmental damage and do little to keep oil off the coast.

Our high-tech products increasingly make use of rare metals, and mining those resources can have devastating environmental consequences. But if we block projects like the proposed Pebble Mine in Alaska, are we simply forcing mining activity to other parts of the world where protections may be far weaker?

The chairman of the Intergovernmental Panel on Climate Change acknowledges it has been a rough few months for his organization. But, he argues, no amount of obfuscation and attacks by conspiracy theorists will alter the basic facts — global warming is real and intensifying.

The Asilomar conference on geoengineering had been touted as a potentially historic event. What emerged, however, were some unexpected lessons about the possibilities and pitfalls of manipulating the Earth’s climate to offset global warming.

Hydro fracturing is a profitable method of natural gas extraction that uses large quantities of water and chemicals to free gas from underground rock formations. But New York City’s concerns that the practice would threaten its water supply have slowed a juggernaut that has been sweeping across parts of the northeastern United States.

The obscenely profitable market for bluefin tuna in Japan has led to years of overfishing and left the world’s bluefin population badly depleted. A ban on the bluefin trade, if adopted at international talks this month, would go a long way toward giving this magnificent fish a chance to recover.

Populations of many of the world’s wild cats are plummeting, with the number of tigers falling to roughly 3,200. In an interview with Yale Environment 360, Alan Rabinowitz, a leading wild cat biologist, lays out a vision of how populations of these magnificent creatures can be brought back from the brink.