Sunday, May 4, 2008

As the evidence of global warming has mounted, many international policymakers and members of Congress have focused on the goal of preventing worldwide temperatures from rising more than 3.6 degrees Fahrenheit, which would require a global cut in greenhouse gases of at least 80 percent by 2050.

Living in denser communities that put people close to their places of work would have a significant effect on emissions. The primary source of greenhouse gases is carbon dioxide, and every gallon of gas burned produces about 20 pounds of CO2.

Living in multiunit residences, rather than detached homes, also conserves energy. Multiunit residences result in 30 to 60 percent less greenhouse gas than isolated houses, according to the Energy Department, because they use less energy for heating and cooling.

-- Juliet Eilperin