· What is climate?
· What climatic belts do you know?
· What is the typical climate of Belarus?
B) Now read the text, translate it and get ready to do the exercises after the text.
Climate
Climate is the aggregate of day-to-day weather conditions over a period of many years. It is the result of the interaction of many different elements, the most important of which are temperature and precipitation.
Climatic patterns are a result of the interaction of three geographic controls.1 The first is latitude. The earth is tilted on its axis2 with reference to3 the plane of its orbit around the sun. As it makes its annual revolution around the sun, first the Northern Hemisphere and then the Southern are exposed to the more direct rays of the sun. During the Northern Hemisphere’s summer, higher latitude locations have longer days, with far northern points experiencing a period of continuous daylight. Daylight periods during the winter months are shorter at higher latitudes, whereas more southerly locations have both longer days and exposure to more direct rays of the sun.
The second control is based on the relationship between land and water. Land tends to heat4 and cool more rapidly than water. In a tendency called continentality, places far from large bodies of water experience greater seasonal extremes of temperature than do coastal communities5. Parts of the northern Great Plains experience annual temperature ranges close to 650C; annual differences of as much as 1000 C (from 500C to – 500C) have been recorded in some locations.
The converse effect occurs at maritime locations, especially on the western coast of continents in the mid-latitudes. These locations have smaller temperature ranges as a result of what is called a maritime influence. Summer and winter extremes are moderated by the movement onshore of prevailing westerly wind systems6 from the ocean. Horizontal and vertical ocean currents minimize seasonal variations in the surface temperature of the water. The moderated water temperature serves to curb7 temperature extremes in the air mass above the surface.
Proximity to large water bodies also tends to have a positive influence8 on precipitation levels, with coastal locations receiving generally higher amounts. The reason for this should be obvious; large water bodies provide greater levels of evaporation and thus increase the amount of moisture in the atmosphere.
The third prime geographic influence on climate is topography. Most obvious is the relationship between elevation and temperature, with higher elevations cooler than lower elevations. The influence of topography can be broader, however, because of its effect on wind flow. If a major mountain chain lies astride a normal wind direction, the mountains force the air to rise and cool. As the air mass cools, the amount of moisture that it can hold is reduced. Precipitation results if the cooling causes the relative humidity to reach 100 percent. Moisture falls on the windward side, and the lee is dry.
Notes:
1. geographic control – географический фактор, воздействие
2. earth is tilted on its axis – ось Земли наклонена
3. with reference to – относительно
4. land tends to heat… – земля имеет тенденцию нагреваться
5. community – местность, территория
6. westerly wind system (westerlies) – западные ветры, западный перенос
7. curb – сдерживать
8. … tends to have a positive influence… – оказывать положительное влияние
Word study
Ex. 1. a) Pronounce correctly the following international words.
| Celsius climate continentality control effect element Fahrenheit horizon | horizontal period region system temperature vertical extreme |
