Английский язык

The effect of global warming on precipitation and agriculture seems to be even stronger. Different temperature at the poles and equator is the main driving force of anthropogenic circulation. Stronger warming at the poles will weaken the circulation. This will change the picture of anthropogenic circulation and therefore – the precipitation distribution.

For North Africa, as it is currently a desert, increase in precipitation will probably have a positive effect. However the USA and Canada will lose under these conditions. The central part of North America is one of the most important agricultural regions in the world, producing huge amounts of maize and wheat. Precipitation in region, already a minimum for its current crops, is expected to reduce significantly. Irrigation will hardly remedy the situation because the level of ground water is already going down in most of this territory because of agricultural consumption. Agriculture will probably manage to adapt to another climate, e.g. by shifting areas under crops to the north. However the main difficulty is in the lack of knowledge – what to expect. Farmers now lose on average every fifth yield because of unfavorable weather. In climate shifts the weather inconstancy will be even more tangible and crop losses may increase catastrophically.

7. Speak on the following topics:

1. Physical manifestation of the greenhouse effect.

2. The natural greenhouse effect.

3. The anthropogenic greenhouse effect.

UNIT XIV

New word and expressions:

inland (n.)– внутренний, территориальный

depression (n.) – впадина

approximately (adv.) – приблизительно

sediment (n.) – осадок

to range(v.) – колебаться

currently (adv.) – в текущее время

to cover (v.) – охватывать, покрывать

border (n..) – граница

permanent (adj.) – постоянный

inflow (n.) – приток

numerous (adj.) – многочисленные

to reflect (v.) – отражать, reflection (n) отражение

to prevail (v.)– преобладать

to derive (v.)– происходить

to spawn (v.) – метать икру

prolific (adj.) – плодородный, изобилующий

salient (adj.) – заметный, выпуклый

Part I

The Caspian Environment

a) Physical environment

1. The Caspian Seal, called the jewel of continents, Asia and Europe, is the world's largest inland body of water, encompassing some 44 % of the volume of all inland laces and seas. The Caspian occupies a deep continental depression within the largest catchment basin in Europe (about 3.100.000 km2). it is width ranges from 435km to a minimum of 196km. It has no natural connection to the world's oceans and its surface level is currently around -26.5m below MSL. At this level, its total coastline is some 7.000km in length, its surface area 386.400km2 and its water volume about 78.700km3.

2. The Caspian can be divided into three parts: the northern, middle and southern. The border between the northern and middle parts runs along the edge of the North Caspian shelf between Chechen Island (near the Terek river mouth) and Care Tiub-Karagan (at Fort Shevchenko). The border between the middle and southern parts runs from the Apsheron threshold connecting Zhiloi Island in the west with Care Kuuli in the east (north of Turkmenistan). The northern part covers about 25 % of the total surface area, while the middle and southern parts cover about 37 % each. However, water volumes in the northern part account for a mere 0.5 %, volumes in the middle part make up 33.9 %, while southern part contains 65.6 % of the Caspian waters. These volumes are a reflection of the bathymetry of the Caspian: the northern part is very shallow, being mainly less than 5m in depth; in the middle part the main feature is the Derbent Depression, which reaches depth over 500m; and the South Caspian Depression, with its deepest point being 1025m below the surface.

3. Around 130 large and small rivers flow into the Caspian, nearly all of which flow into the north or west coasts. The largest is the Volga River, which drains an area of 1.400.000km2 into the northern part of the Caspian. Over 90 % of the inflowing freshwater is supplied by the 5 largest rivers: Volga, Kura, Terek, Ural and Sulak. The rest is accounted for by the Iranian rivers and the smaller streams on the western shores, since there are no permanent inflows on the eastern side. The Volga water is fresh (total ionic content from 200 to 400 mg/1), and enters the Caspian through the west part of the delta, flowing south along the west coast. Because the Caspian is so shallow there, no saline stratification can become established. The Volga and Caspian waters mix rapidly, causing a marked increase in salinity as on moves away from the delta. The Caspian s average salinity is slightly over 1/3 that of seawater, such that it may be classified as brackish and mesohaline, a rather unique hydro chemical environmental.