Trouble in the air, double on the ground – 10 February 2012, The Economist

Could a fresh row over airline emissions lead to a global trade war? That is the scariest prospect raised by China’s objections this week to the European Union’s new plan for controlling greenhouse-gas emissions from aeroplanes. The scheme, which came into effect on January 1st, forces airlines flying into the EU to buy tradable carbon credits as part of its broader emissions-trading system.