RAIN, ICE, AND GEOGRAPHY

Why is it wetter on one side of a mountain range?

It's much more wet on one side of a mountain than the other because of a process known as orographic precipitation. Orographic precipitation causes air to rise up the side of a mountain range and cool, creating precipitation and storms. The storms deposit a great deal of precipitation on that side of the mountain and create a rain shadow effect on the opposite side of the range. The Sierra Nevada mountains are an excellent example of orographic precipitation because the mountains of the western Sierras receive considerable rainfall (far more than California's Central Valley), while the eastern Sierras of Nevada are quite dry.

What is a rain shadow?

When the moisture in the air is squeezed out by orographic precipitation, there's not much left for the other side of the mountains. The dry side of the mountains experiences a rain shadow effect.

Why is Greenland called green when it is mostly covered in ice?

When Scandinavian explorers first discovered the large island north of Iceland in the late-tenth century, they wished to attract more settlers to the land, and so they named it Greenland, according to some sources. Another explanation is that the island was actually named "Gruntland," the word "grunt" meaning "shallow bay." The name was later mistranslated on maps, becoming Greenland. While much of the island is inhospitably covered by a huge glacier, the southern coastline does actually have vegetation and has served as good fishing ground. The Little Ice Age of the fifteenth century decimated the Viking settlements, however.

Which continents have the highest and lowest average elevations on the planet?

Antarctica has the highest average elevation (7,546 feet [2,300 meters] above sea level), much of which is due to the permanent glacial ice. Australia has the lowest average (984 feet [300 meters] above sea level).

How much ice is there covering Antarctica and Greenland?

Most of the world's fresh water is stored in the form of ice covering the continent of Antarctica: an amazing 70 percent! Furthermore, 90 percent of all the Earth's ice is also found in the southernmost continent. The ice covering Antarctica is as much as two miles (3.2 kilometers) thick in places. Scientists have found that the ice is getting deeper in the central part of the continent, while on the outer edges it seems to be melting. Although scientists do not understand why yet, the ice on the western side of the continent seems to be getting thicker overall, while in the east it is getting thinner. Overall, the total amount of ice appears to be at stable levels, in contrast to ice in the Northern Hemisphere. It is difficult to say how much ice is covering Greenland, because there it is melting so quickly. In the late 1990s, the large island had an ice cap that contained about 720,000 cubic miles (three million cubic kilometers) of ice. At that time, the ice was melting at a rate of about 21.6 cubic miles (90 cubic kilometers) per year. As of 2005, that rate has increased to 36 cubic miles (150 cubic kilometers).

A satellite image of Greenland shows a large island almost entirely covered by a thick sheet of ice. (NASA)

A satellite image of Greenland shows a large island almost entirely covered by a thick sheet of ice. (NASA)

Where does it snow on the equator?

Mountainous regions on or near the equator regularly get snow. For example, it snows in the Andes Mountains in Ecuador, and in Africa snow falls on Mt. Kenya and Mt. Kilimanjaro.

VOLCANOES

What are the two major characteristics of volcanic eruptions?

A volcano can experience violent eruptions or less explosive, more effusive eruptions that produce wide-ranging lava is tics of a volcano are based on the silica

It is possible to find snow near the equator, such as atop Mt. Kilimanjaro in Tanzania.

It is possible to find snow near the equator, such as atop Mt. Kilimanjaro in Tanzania.

flows. In general, the eruptive character-and water content of the magma.

 
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