Although we still have much progress to make on reducing emissions, new research suggests the situation could be worse.

According to a study by the Desert Research Institute, pollutant levels at the beginning of the 20th century were two to five times higher than current levels of pollution. Researchers attribute the decrease in pollution levels to the advent of more efficient coal-burning technologies, as well as legislation aimed at reducing emissions.

In a slow-motion shock to environmentalists worldwide, European countries are turning back to coal to fire new power plants. At a time when India and China are ramping up production in their outdated coal-burning facilities, the last place anyone expected to see a coal resurgence was in the generally progressive nations of Western Europe. Most turning again to coal are hamstrung by record oil and natural gas prices; Italy and Germany have the added stress of having banned new nuclear plants as an alternative.

Big lumps of sooty coal hardly seem like the future of energy, but that's exactly what the U.S. Department of Energy predicts. Consumption of the fossil fuel-the main source of greenhouse gas and a major contributor to acid rain, smog and mercury poisoning-will hit 10.6 billion tons a year by 2030, a near doubling of the 5.4 billion tons burned in 2003, according to the agency.