The UN conference on climate change that begins December 7 in Copenhagen is supposed to produce new targets for emissions reductions, but experts say major countries are at odds on the ultimate goal …

Loss of forests is a major contributor to greenhouse-gas emissions. Plans to devise a policy tool for using trees for carbon dioxide sequestration are now under way.

President Barack Obama says he will seek vigorous climate-change policy. Efforts to curb greenhouse gases pose considerable economic pitfalls, as well as opportunities.

While some experts fault demand increases for record-high oil prices, others say production and market issues reflect price hikes are more complicated.