The European Commission has just made a Google Earth overlay available showing annual greenhouse gas (GHG) emissions by 10 square kilometer quadrants. The overlay can be manipulated to show estimates from every year beginning in 1970. One of the most fascinating features is the GHG emissions on the oceans, from shipping lanes. All are green (fewer GHG tons), but one route stands out as by far the busiest, from Hong Kong and Japan through the Straits of Malacca and the Suez Canal to northern Europe.
The application is useful for broad reviews of GHG emissions by same-sized areas, though the zoom feature does not provide high resolution enough photography to discern differences at the smallest area level.