Ice Ages & Global Warming
Through out its history, the Earth has continuously warmed and cooled. The most recent ice age began 20-30 million years ago.
At the time, Antarctica was still undergoing radical changes. It had recently separated from Gondwanaland and began its slow drift southward. As the ice age continued, snow began falling on the continent creating the first layers of the ice caps for which Antarctica is famous.
Eventually, the ice age peaked approximately 2-3 million years ago. By then, Antarctica had reached its approximate position at the South Pole and was well on its way to building its 8,000 foot (2,400 meter) blanket of ice and snow.
Since that time, the Earth has warmed slightly. Although several mini ice ages (such as the "Little Ice Age") have occurred, the Earth's temperature during the last 10,000 years rarely fluctuated more 2°F. The "Little Ice Age" occurred between 1400-1700 AD. when average summer temperatures dropped 4-5°F (2-3°C) below temperatures today.
Adding to the concern always associated with the Earth's temperature swings is a man-made phenomena called "The Greenhouse Effect".
The Greenhouse Effect is associated with the production of carbon monoxide from automobiles and factories. Plants and trees normally absorb carbon monoxide and convert it into oxygen through photosynthesis. However, the rate of carbon monoxide product is exceeding the ability of plants to convert it. As a result, the excess remains aloft in the atmosphere where it acts like a blanket. This blanket traps heat from the Sun that is normally reflected back into space. This trapped heat warms the Earth faster than normal.
Its theorized that a temperature increase as little as 2-5°F (5-10°C) could melt large areas of the Antarctic ice cap. The water from the run off would raise sea levels 1-6 feet (0.3-2 meters). In terms of real estate, estimates equate a one foot increase in sea levels to approximately 2-8 miles (3.3-13.3 km) of lost land due to flooding. enough to flood coastal cities and damage inland waterways and lowlands such as the Mississippi River Valley. The losses caused by the flooding would be immeasurable.
Try "Ushuaia Underwater". See What happens to the Ushuaia, Argentina as rising temperatures raise the sea levels around the most southern city in the world (not counting the hamlet of Porto Williams) .
After you're done with Ushuaia, take a look at the Greenhouse Effects Visualizer ("GEV"). GEV is part of a collaborative learning project at Northwestern University, in Chicago. GEV uses actual scientific data to generate color images of the atmosphere based upon the settings selected by you.
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