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Equator

 

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Overview
Run your finger along the equator on a globe. What do you see in your mind's eye as your finger passes over continents and oceans? Tropical rain forests? Houses on stilts? Blazing temperatures? Stop your finger on the east African country of Kenya and be prepared for new impressions. Lying on the equator in the southwestern corner of Kenya is the Maasai Mara National Reserve - a nature preserve that defies the usual image of the equatorial tropics. This reserve is a part of the Serengeti-Mara ecosystem. Here you will find not rain forests, but woodlands and savanna. Two million years ago, volcanic and tectonic activity pushed up the lush forest floors of this region, creating a plateau 1,520 meters (5,000 feet) above sea level. At this elevation, the warm ocean winds were cut off, forests disappeared, and volcanic ash settled over the highlands, creating the rolling plains of today. Temperatures can reach 38 C (100 F) and cool to 10 C (50 F). Dramatic volcanic action also produced Mount Kenya. Once higher than Mount Everest, Mount Kenya now stands 5,200 meters (17,000 feet) high and is crowned with snow. Snow! On the equator? Why doesn't the snow melt? First, as one ascends from sea level, the temperature decreases. In fact, according to the adiabatic lapse rate, for every thousand feet, the temperature drops approximately 3.1 C (5.5 F). Second, the shiny surface of the snow reflects the sun's rays, keeping the snow frozen. (This effect is called the albedo.) Third, the snow is so densely packed at the peak that the lower layers of snow cool the surface layer, counteracting the warming effects of the sun. Life in the shadow of Mount Kenya may defy our equatorial image, too. For a thousand years, the nomadic Maasai have shared their home with wildebeest, lion, and giraffe. More precious to the Maasai are the herds of cattle upon which their livelihood, wealth, and prestige depend. The Maasai villages are built with the materials at hand-mud, cow dung, and sticks. Women are responsible for the construction of the family boma. Life in the manyatta follows traditional patterns, and the roles of its members are clearly defined. Boys take care of the cattle, girls help their mothers, and elders enjoy their honored roles as village leaders. Although life in nearby cities offers modern conveniences, many Maasai prefer the path of their ancestors under the direct rays of the equatorial sun.

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