A Contribution to the Encyclopedia of Climate and Weather

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Iceland
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.224.1246; http://www.gfdl.gov/cms-filesystem-action/user_files/yim/files/aerosols.pdf

Aerosols- Aerosols are fine solid or liquid particles suspended in the atmosphere, where they reside typically for days to weeks before settling to the ground or being washed out by rain or snow. They arise both from natural sources (such as desert dust, sea spray and volcanic eruptions) and from human activities involving burning of fossil fuels and vegetation. Visible forms of atmospheric aerosol plumes include dust, smoke, smog and haze. Aerosol particles are small, but numerous, and often comprise of a number of inorganic and organic substances. They adversely affect human health, and thus are regulated as air pollutants. As an integral component of the Earth’s climate system, aerosols interact strongly with sunlight, and provide condensation nuclei for cloud formation. Man-made aerosols alter the climate in fundamental ways. History of Study Modern aerosol science finds its root in the so-called Age of Enlightenment, during which many hypotheses on the origin of aerosols were postulated. Scattered observations made in the 19 th century helped rule out some of them (such as earthquakes, thunderstorm lightning and meteoric dust). In 1783, Benjamin Franklin, then the United States ambassador to France, speculated that a volcanic eruption in Iceland