In meteorology, an air mass is a volume of air defined by its temperature and water vapor content. Air masses cover many hundreds or thousands of square miles, and adopt the characteristics of the surface below them. They are classified according to latitude and their continental or maritime source regions. Colder air masses are termed polar or arctic, while warmer air masses are deemed tropical. Continental and superior air masses are dry while maritime and monsoon air masses are moist. Weather fronts separate air masses with different density (temperature and/or moisture) characteristics. Once an air mass moves away from its source region, underlying vegetation and water bodies can quickly modify its character. Classification schemes tackle an air mass' characteristics, and well as modification.
Read more about Air Mass: Classification and Notation, Characteristics, Movement and Fronts, Modification
Famous quotes containing the words air and/or mass:
“It so happened that, a few weeks later, “Old Ernie” [Ernest Hemingway] himself was using my room in New York as a hide-out from literary columnists and reporters during one of his rare stopover visits between Africa and Key West. On such all-too-rare occasions he lends an air of virility to my dainty apartment which I miss sorely after he has gone and all the furniture has been repaired.”
—Robert Benchley (1889–1945)
“Compare the history of the novel to that of rock ‘n’ roll. Both started out a minority taste, became a mass taste, and then splintered into several subgenres. Both have been the typical cultural expressions of classes and epochs. Both started out aggressively fighting for their share of attention, novels attacking the drama, the tract, and the poem, rock attacking jazz and pop and rolling over classical music.”
—W. T. Lhamon, U.S. educator, critic. “Material Differences,” Deliberate Speed: The Origins of a Cultural Style in the American 1950s, Smithsonian (1990)