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Ocean vertical structure

  1. A) Compare BASIC and PASCAL; b) Speak on the difference in BASIC and PASCAL structures.
  2. Analyze Figure 11.5. and say in what case a suspended concrete structure is possible / impossible to build and explain your choice.
  3. ANCIENT STRUCTURES
  4. Circulations in the vertical and horizontal planes
  5. Civil engineers turn complex ideas into reality. They help make some of the most innovative structures in the UK and abroad.
  6. COMPANY STRUCTURES
  7. Deep ocean circulation

The oceans occupy 71 per cent of the earth's surface, with over 60 per cent of the global ocean area in the southern hemisphere. Three-quarters of the ocean area is between 3,000 and 6,000 m deep, whereas only 11 per cent of the land area exceeds 2,000 m altitude.

a Vertical

The major atmosphere-ocean interactive processes involve heat exchanges, evaporation, density changes and wind shear. The effect of these processes is to produce a major oceanic layering that is of great climatic significance:

1 At the ocean surface, winds produce a thermally mixed surface layer averaging a few tens of metres deep poleward of latitude 60 °, 400 m at latitude 40 ° and 100-200 m at the equator.

2 Below the relatively warm mixed layer is the thermocline,
a layer in which temperature decreases and density increases (the pycnocline) markedly with depth. The thermocline layer, within which stable stratification tends to inhibit vertical mixing, acts as a barrier between the warmer surface water and the colder deep-layer water. In the open ocean between latitudes of 60 ° north and south the thermocline layer extends from depths of about 200 m to a maximum of 1,000 m (at the equator from about 200 to 800 m; at 40 ° latitude from about 400 to about 1,100 m ). Poleward of 60 ° latitude, the colder deep-layer water approaches the surface. Within the thermocline layer, the location of the steepest temperature gradient is termed the permanent thermocline, which has a dynamically inhibiting effect in the ocean similar to that of a major inversion in the atmosphere. However, heat exchanges take place between the oceans and the atmosphere by turbulent mixing above the permanent thermocline, as well as by upwelling and down-welling involving deep-layer water. During spring and summer in the mid-latitudes, accentuated surface heating leads to the development of a seasonal thermocline occurring at depths of 50 to 100 m. Surface cooling and wind mixing tend to destroy this layer in autumn and winter.

3 Below the thermocline layer is a deep layer of cold, dense water. Within this, water movements are mainly driven by density variations, commonly due to salinity differences (i.e. having a thermohaline mechanism).

The ocean may be viewed as consisting of a large number of layers, the topmost subject to wind stress, the next layer down to frictional drag by the layer above, and so on; all layers being acted on by the Coriolis force. The surface water tends to be deflected to the right (in the northern hemisphere) by an angle averaging some 45 ° in the surface wind direction and to move at about 3 per cent of its velocity. This deflection increases with depth as the friction-driven velocity of the current decreases exponentially. On the equator, where there is no Coriolis force, the surface water moves in the same direction as the surface wind. This theoretical Ekman spiral was developed under assumptions of idealized ocean depth, wind constancy, uniform water viscosity and constant water pressure at a given depth. This is seldom the case in reality, and under most oceanic conditions the thickness of the wind-driven layer is about 100 to 200 m.

Вправа 2.

Прочитайте наступні слова і визначте їх відповідності
в Російській мові:

Hemisphere, thermocline, pycnocline, process, temperature, stratification, vertical, barrier, maximum, location, gradient, dynamically, upwelling, seasonal, exponentially, theory, spiral, idealize, constant, reality.

Вправа 3.

Визначте, до яких частин мови належать такі слова; напишіть відповідні англійські скорочення для кожного з них (v., adv., n., adj., conj., part., prep., pron.):

Vertical, evaporation, as, with, which, within, colder, has, however, termed, occurring, mainly, thickness.

Вправа 4.

У правій колонці знайдіть російські еквіваленти наступних англійських словосполучень:

 1. heat exchange2. vertical mixing3. temperature gradient4. water movement5. density variation6. wind stress7. wind direction8. ocean depth9. surface layer  a. глибина океанаb. рух водиc. напрямок ветраd. поверхневий слойe. температурний градіентf. теплообменg. вертикальне перемешіваніеh. зміни плотностіi. вітрове вплив

Вправа 5.

Заповніть, де це можливо, таблицю, вставивши відсутні частини мови.

 v.  n.  adj.  adv.
 produce extend  significance variation  stable  dynamically relatively

Вправа 6.

Прочитайте наступні вирази:

206 km; 1-2 m / day; 30 ° C; 1700; 1,367; 2.68931.

Вправа 7.

Вставте відповідний привід і підберіть визначення до кожного слова: Off about up away for down on out.

 1. pass ... 2. make ... 3. bring ... 4. clear ... 5. cut ... 6. do7. fall8. fill  a. вияснятьb. продолжатьc. расшірятьe. направлятьсяf. сніматьg. покідатьh. визиватьi. скорочувати

Вправа 8.

Прочитайте текст і знайдіть в ньому відповіді на наступні питання:

1. Яка середня швидкість апвеллинга?

2. Від чого вона залежить?

3. Де розташований основний регіон апвеллинга?

(Контрольний час - 7 хвилин)




Length of day | Energy transfer within the earth-atmosphere system | Effect of the atmosphere | Composition of the atmosphere | Variation with height | Variations with latitude and season | The layering of the atmosphere | Ozone layer reduction | The general circulation | Circulations in the vertical and horizontal planes |

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