Atmosphere of Earth surface. The refractive index of air depends on temperature, giving rise to refraction effects when the temperature gradient is large. An example of such effects is the mirage. "Atmospheric circulation" is the large-scale movement of air through the troposphere, and the means (with ocean circulation) by which heat is distributed around Earth. The large-scale structure of the atmospheric circulation varies from year to year, but the basic structure remains fairly constant because it is determined by Earth's rotation rate and the difference in solar radiation between the equator and poles. The first atmosphere consisted of gases in the solar nebula,
Live Earth concert, Washington, D.C. Gore speak and Brooks play from what event organizers called a "JumboTron" outside the immediate viewing area. Due to last minute organizing, there were no working audio speakers that could project sound to the JumboTron viewers. Live Earth concert, Washington, D.C. The Live Earth concert in Washington, D.C., officially known as "Mother Earth", was held on the National Mall in Washington, D.C., United States and was sponsored by and held on the premises/venue of the Smithsonian's National Museum of the American Indian. It was only hours before the Washington D.C. concert was scheduled to begin that organizers were able to