3. Translation into Russian

1. The atmosphere is made up of gases. The two that are of the most concern to modem scientists are carbon dioxide and ozone.

2. The four conditions that cause weather are temperature, moisture, atmospheric pressure, and wind.

3. Changing atmospheric conditions can create violent weather.

4. Thunderstorms, tornadoes, hurricanes, and typhoons are among the most spectacular displays of weather and can be very dangerous and destructive.

5. Latitude, altitude, and proximity to land and water are controls that determine climate patterns.

6. Vegetation responds directly to climatic conditions and plant-growth patterns. Global vegetation regions are related to global climate regions.

7. Global vegetation regions include forest-lands, grasslands, vegetation in dry and cold regions, and mountain vegetation.

8. Heat energy does not pass through the air as easily as sunlight does. The lower atmosphere temporarily traps the heat, much like a greenhouse traps warmth. In a greenhouse the sunlight passes through the glass roof and walls and warms the air. The heat, however, does not immediately pass back through the glass to the outside air. Instead the heat is temporarily trapped in the warm air, keeping the greenhouse warm, just as heat energy is temporarily trapped in the lower atmosphere, keeping the earth warm. This process, called the greenhouse effect, constantly warms the earth.

3. Complementary texts

VIOLENT WEATHER

Thunderstorms, tornadoes, hurricanes, and typhoons can create a spectacular display of weather — a display that also can be dangerous. Such unstable weather conditions result from certain combinations of temperature, moisture, atmospheric pressure, and wind.

Thunderstorms occur whenever hot and humid air rises rapidly. Electrical charges build up in the rising air as moisture condenses, clouds form, and rain begins to fall. When the negative charges in the clouds make contact with the positive charges on the earth’s surface, a streak of lightning flashes across the sky. Thunder, the shock waves caused by the lightning bolt, rumbles after the flash. Lightning is one of nature’s most dangerous elements. Each lightning bolt carries a powerful electric charge. When these charges touch people or buildings, they can cause death and property damage.

Tornadoes, with winds of between 480 and 800 km per hour, rank among the most violent of nature’s storms. The twisting, funnel-shaped cloud of a tornado often descends from the clouds of a severe thunderstorm. As the tornado gets closer to the earth’s surface, its winds swirl everything in its path into the funnel. It is not uncommon for the powerful winds to lift small buildings and move them hundreds of yards. Although very destructive, tornadoes are usually small. The path of destruction of an average tornado measures only a few hundred meters wide and about 25 km long. Tornadoes occur throughout the world.

Large low-pressure areas with strong winds can create violent storms over tropical ocean areas, usually in the late summer and early fall. The storms that form over the Atlantic Ocean and the Gulf of Mexico are called hurricanes. Similar storms that form over the Pacific Ocean are called typhoons. Winds must blow 120 km per hour or more before a storm is classified as a hurricane or a typhoon. Once formed the storms are circular, with “eyes” of very low pressure at their centers. The air in the eye usually remains calm, but winds swirl around it at high speeds. Hurricanes and typhoons typically measure 160 to 960 km across. The eye of most storms has a diameter of 15 to 40 km.

Hurricanes and typhoons move in unpredictable patterns, eventually pounding coastlines with high winds, high waves, and heavy rains. Because they gather their strength from the warm ocean waters, however, they usually die out quickly once they reach land — not, however, before causing tremendous damage to coastal areas.

Unlike other storms, hurricanes and typhoons have names. Each year the National Hurricane Center in Coral Gables, Florida, chooses an alphabetical listing of names to identify the season’s storms. The names selected for the first three hurricanes of 1989 were Allison, Barry, and Chantal.

EL NlftO

The Peru Current, which flows northward along the western coast of South America, sometimes behaves in ways that scientists do not fully understand. Because this usually occurs soon after Christmas, it is called El Nino, Spanish for “The [Christ] Child”.

Upwelling. Upwelling — a climatic condition brought on by winds that persistently drive water away from the coast — is of great biological importance to the west coast of South America. When upwelling occurs, the cold subsurface water of the Peru Current rises to replace the usually warm water. The rising, cooler water is rich in nutrients for phytoplankton — microscopic ocean plants. Tiny marine animals called zooplankton feed on the trillions of phytoplankton. At the upper end of the food chain, fish thrive on the abundance of food. This process makes the coasts of Ecuador, Peru, and Chile among the world’s most productive fishing areas.

Occasionally northerly winds replace the prevailing southerly winds and the cold Peru Current moves westward. In its place comes a warm current — El Nino. The warm waters of El Nino stop the upwelling and completely break down the normal ecological system. Most of the marine life moves in search of plankton-rich cooler waters and the fishing fleets follow.

Effects of El Nino. In 1972 El Nino appeared quite suddenly. Warm water herded fish into a narrow band of cool water along the coast of Peru. Several thousand fishing vessels closed in. Together they caught as much as 180,000 tons of fish in a day.

When El Nino stopped, upwelling resumed. But most of the fish were gone. Without fish to consume the plankton, they overmultiplied and exhausted their food sources. Billions died and decomposed on the ocean floor. Decomposition used laige quantities of the water’s oxygen, making the ocean off Peru unable to support fish until balance was restored.

Worldwide influences. Scientists now recognize that El Nino’s influences reach far beyond the west coast of South America. Indeed, it is now known that El Nino interacts with worldwide weather patterns. Rainfall shifts from the normally wet western Pacific toward the drier eastern Pacific. The Philippines and Indonesia experience drought. Intense heat and drought sweep Australia. Ecuador and Peru receive heavy rain and floods take heavy tolls in human lives and property losses.

Record-breaking snowfalls paralyze the east coast of North America, while western Canada and Alaska experience unusually mild winters. All result from a still-unexplained change in the weather.