Boston Globe: GLOBAL WARMING IS a planet-sized problem, so policy solutions tend to aim for the grandest possible scale. The signatories of the Kyoto Protocol have pledged to cut their greenhouse gas emissions at a national level, while laws in various countries and states seek to reform entire industries. For individuals, the picture is very different. Environmentalism often boils down to small lifestyle choices, like turning down the thermostat and screwing in the squiggly light bulbs – gestures …