Some interesting suggestions from folk on here, however, the cost would be considerably high for some of the aforementioned ideas. A short-term (albeit a big help) would be to reduce soot! Soot—also known as black carbon—heats up the atmosphere because it absorbs sunlight. Black things do. That is basic physics. For years the institutions that focus on climate policy have played down the role of pollutants such as black carbon that stay in the atmosphere for a short time, that soot has been discovered to be a leading cause of snow and ice melting in the Arctic and the Himalayas, soot has a much faster influence on temperature than CO2, and that it is relatively easy to reduce soot. At least then polar bear will stand a greater chance than if we don't act now! We need to begin somewhere.