According to the Climate Theory convection cells wrap around the Earth like a huge insulating blanket. These cells are arranged in bands around the Earth. A convection cell is a system in which a fluid or gas is warmed, loses density and is forced into a region of greater density. The cycle repeats and a pattern of motion forms. Convection cells in Earth's atmosphere are responsible for the blowing of wind. Energy is transferred between the earth's surface and the atmosphere via conduction, convection, and radiation. Convection transmits heat by transporting groups of molecules from place to place within a substance. Convection occurs in fluids such as water and air, which move freely. In the atmosphere, convection includes large- and small-scale rising and sinking of air masses and smaller air parcels. These vertical motions effectively distribute heat and moisture throughout the atmosphere and contribute to cloud and storm development (where rising motion occurs) and dissipation (where sinking motion occurs). To understand the convection cells that distribute heat over the whole earth, let's consider a simplified, smooth earth with no land/sea interactions and a slow rotation. Under these conditions, the equator is warmed by the sun more than the poles. The warm, light air at the equator rises and spreads northward and southward, and the cool dense air at the poles sinks and spreads toward the equator. As a result, two convection cells are formed. Speed up the Earth's rotation, add the tilt and the Earth is exposed to more angles of sun's rays and we get four convecting atmospheric cells. A little more going on but the same simple principle.... Where there is cold, dry winds sinking back to the surface of the Earth we see areas of dry desert conditions. Where there is rising winds between atmospheric convection cells, there is warm, moist air and rain. Under these cells, Earth is moist and lush with vegetation of all kinds. This can be seen especially when looking down at Africa and you can see bands of lush green, desert and lush green. The above weather map shows storm systems moving across the middle of Africa, the northern part of Africa remains dry. Could this climate pattern change? Certainly! The possibility of Earth's patterns could change, just over a long period of time. The Climate Theory tries to explain our observations of dry land masses compared to moist, green land masses. We love Earth, that's why we try to understand this beautiful marble in space.
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Mrs. TaylorI love science! Everything about the world is interesting and never boring. I love to study plants, animals, insects, and people. My favorite subjects are my students who are the most unique organisms on the planet! Categories |