A 20 pct CO2 cut 'pretty good' ?

A pedestrian walks through thick smoke caused by the burning of coal ovens at a roadside in Kolkata December 9, 2009. A 20 percent cut in greenhouse gases by rich nations would be a "pretty good" result for a U.N. climate summit even though it falls short of developing nations' hopes, the head of the U.N. climate panel said on Tuesday. [Agencies]