Got a question? Ever wondered about something related to geography? Then ask away here. Every two weeks, Joe Blanton, director of our Research Correspondence division, will post answers to three of the most interesting questions received via e-mail. Unfortunately time constraints preclude individual e-mail responses.
Saved by the Web ...
I have found a wounded eagle in the forest near my home here in Lebanon. It has a broken wing. Can you tell me how to take care of it?
Reading this plea brought on more than a little concern, since none of us in the office know how to nurse a wounded eagle back to health. But as fortune would have it, National Geographic is hosting a program on birds of prey in our Explorers Hall museum here in Washington, D.C. One of the participants, Ed Clark, an avian expert with the Wildlife Center of Virginia, offered to shoot some suggestions through the wires. Several days later, an e-mail from Lebanon reported that the eagle is making good progress and that another ailing eagle is receiving care as well. Chalk one up for the Internet!
Why is it that many of the worlds deserts are located on the west sides of
continents? You find them in the western U.S. and along the west coasts of South America and Africa.
Its certainly true when you look at the world map that a number of deserts lie on the west coasts of continents. But they exist other places as well. A more consistent trend finds them straddling the Tropics of Cancer and Capricorn. This is due in part to warm, water-laden air that rises from equatorial regions and releases rains in the tropics as it moves toward the Poles. Later it descends, minus its moisture, in the subtropical latitudesperpetuating the aridity.
In one of natures paradoxes, deserts can exist next to oceans. Examples would be the fog-banked deserts of South America and Africa, which owe their existence largely to cold ocean currents that flow from Antarctic regions toward the Equator. The Peru Current streams along South Americas west coast off the Atacama and Peruvian Deserts. The Benguela Current sweeps the Namib Desert on the southwestern edge of Africa. The cool water of these currents brushing against warm coastal air throws off blankets of fog, which trap moisture at the surface level and prevent the moist air from rising to form rain clouds. Such fog can quench aridity, but winds along the western fringes of South America and Africa flow parallel with the coast. These southerly winds hold fog near the shore so that little moisture reaches the desert realms.
I see on the map a tiny speck of something in the North Atlantic west of the British Isles called Rockall. What is that?
Imagine sailing along in the open ocean, far from any continental landform or island, and coming upon a huge rock rearing 70 feet (21 meters) above the sea. Thats just what would happen if you were sailing in an area 220 miles (354 kilometers) west of Scotlands Outer Hebrides. Youd see Rockall, the giant rock in the ocean. Rockall sits on a seamount, an undersea mountain, on the Mid-Atlantic Ridge out in the open ocean.
The big rock, inhabited only by sea birds, was formally annexed by Great Britain in 1955. Rockall is valued not so much for the rock itself but for what surrounds it: territorial waters brimming with fish and a seafloor rich in oil fields.
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