Slashing plane emissions a lofty goal, but progress elusive

The aircraft industry is facing growing criticism over greenhouse gas emissions that are set to soar as more people take to the skies, but experts say game-changing technology for cleaner planes is still decades away.

Cheap oil is blocking progress on climate change

The relationship between supply and demand, a fundamental economic concept, holds that when the price of something rises, people use less of it. Similarly, when prices fall, they use more.