turbulent areas, however, they usually are fairly close to the ground and do not affect aircraft. When you see dust devils or dirt devils, this represents swirling air that can extend as high as four thousand feet above the earth, often looking like tornadoes of dust. Waterspouts over areas of water involve the same phenomenon. Warm air and turbulence sucks water up into the atmosphere, leading to waterspouts. Dynamic or induced tertiary circulations results in things like eddies in the atmosphere, turbulence, and Foehn winds. Eddies are areas of circulation or turbulence when the wind happens to be flowing over rough terrain, which can include mountains, buildings, or man-made obstructions. An Eddie will form on the lee side of these areas. You can also see eddies in the ocean, found over cold deeper ocean waters. These are actually good for fish near the surface of the ocean. This is because they essentially suck up nutrients from deep inside the ocean and bring them to the surface. The National Ocean service names some of the larger eddies they can see. In the atmosphere, most eddies are set up as circular motion straight winds that suddenly encounter rough terrain of any kind.
LAKE EFFECTS You have probably heard about Lake effect snow. This is common in North America in the Great Lakes region. It happens when there is very cold air below the freezing temperature of water over the warmer lake waters. Some of this Lake water evaporates, leaving behind warmer air that is more saturated with water vapor. As the air cools over land, it dumps this precipitation over the ground. Quite often this means a great deal of wet snow. Lake effect snow tends to affect weather within twenty-five miles from the shoreline, although you can see dumping of snow as far away as a hundred miles from the shoreline. Places like Buffalo New York are fairly close to a large body of water, so you often see this type of snow entering the wintertime. You will not see it after February, however, largely because the lake has frozen over and it is impossible to steal water from it.
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