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1. Trade winds

are caused by lifting over the heat equator and the subsequent air movements from the sub tropical anticyclones

blow towards the sub tropical anticyclones

only blow in the winter months.

blow from the equatorial low pressure systems throughout the year.

2. The warm temperature climatic zone is

approximately 20° - 35° of latitude and covers the high pressure desert regions of the world.

approximately 35° - 40° of latitude and provides a wet summer season and a dry cold winter

approximately 35° - 40° of latitude and provides a warm dry summer with a cool wet winter

approximately 35° - 40° of latitude and is under the influence of polar front depressions throughout the year

3. Jet streams

have a speed in excess of 80 kt.

are caused by a large difference in mean temperature in the horizontal.

only occur in the troposphere.

are located above the tropopause.

4. Jet stream main locations are

only in association with the polar front.

in the warm air some 400 nm ahead of a warm front and some 200 nm behind a cold front and near the sub tropical highs.

in the warm air some 400 nm ahead of a warm or cold front and near the subtropical highs

in association with the polar front and with mountain waves.

5. The outflow from the Siberian High

is northwesterly over Japan, northeasterly over southeast Asia and easterly over Europe.

is the source of Polar Maritime air.

is northwesterly over Japan, northerly and northeasterly over China and northerly over the whole of India

is evident throughout the year.

6. Northern hemisphere summers tend to be

warmer than the southern hemisphere and the winters are colder

colder than the southern hemisphere due to the smaller amount of solar radiation.

warmer than the southern hemisphere and winters are warmer too.

colder than the southern hemisphere because of the large land masses.

7. The areas of greatest rainfall are

in central North America in summer due to the large convective cloud formations.

in the equatorial regions.

in the polar regions.

those where there is much polar front depression activity.

8. Tropical Revolving Storms are

can be very active well inland.

can travel at speeds of 100 kt.

easily predictable.

a summer weather feature.

9. The Savannah climatic zone is

approximately 10° - 20° of latitude and provides a wet winter season and a dry hot summer.

approximately 10°- 20° of latitude and provides dry trade wind conditions in winter and a wet summer season.

approximately 20° - 30° of latitude and provides very dry desert conditions throughout the year.

approximately 10° - 30° of latitude and has a period of long rains in spring and autumn, but is never dry.

10. The Polar Front is

near the poles.

the region where warm sector depressions develop.

only apparent over the Atlantic ocean.

the boundary surface between polar continental and tropical continental air

11. The most numerous and frequent thunderstorms occur

in association with tropical revolving storms

in association with the ITCZ over north Africa

over the east Indies area (Java) due to the intense surface heating.

in regions affected by cold fronts.

12. The Tropopause is

the upper limit for jet streams and mountain waves.

is a boundary layer between the troposphere and the stratosphere.

normally the upper limit of weather.

more or less constant for any latitude.

13. The upper winds tend to be westerly outside the tropics because

the thermal winds are westerly on average.

the rotation of the earth is west to east

surface winds are nearly always westerly.

jet streams are usually westerly.

14. The ITCZ is

the boundary between polar air and equatorial air.

the region between the two trade wind systems centred on the heat equator

the boundary region between the two monsoons.

a region of calm winds and layer type clouds with much haze.

15. The average temperature around the equatorial regions

has a very high range of temperatures throughout the year

is always above +40° C

varies on average from winter to summer by only some 5° C

is higher over the sea areas

16. Monsoons are seasonal winds which

develop due to the high pressure over continents in winter and the subsequent low pressure which develops over the same areas in summer

are from the southeasterly direction over the Indian sub continent in summer

are never in combination with trade winds

blow only in the southeast Asia region

17. Trade winds in the southern hemisphere are

southeasterly

southeast at first becoming southwest

usually from the northeast

in opposition to the monsoons

18. The Hadley cell is the name given to

a cell formed by lifted air over the heat equator descending to the sub tropical highs

the centre portion of a jet stream.

the CU cells which continue to form a CB.

an initial bubble of air which is lifted by convection.

19. The large change in the direction of trade winds is caused by

local pressure differences.

an excess of air at height in association with the Hadley cells.

the cyclostrophic force in the equatorial regions.

the change in geostrophic force when crossing the geographic equator.

20. The effect of mountain barriers on temperature is exemplified by the following

the Ural mountains of West Russia prevent most of the cold Siberian air reaching Europe in summer

the Rocky mountains of North America prevent cold Pacific air reaching inland, so summer temperatures to the east of the mountains are high

the Himalayas prevent warm dry air from Russia reaching India and Pakistan

European temperatures are low in winter because there is no barrier to prevent cold Atlantic air crossing the area.

21. Dust storms and haze are most common

with the Haboobs in winter

in temperate latitudes

in unstable air with low pressure

in association with the sub tropical anticyclones over land

22. Near the equator upper winds tend to be

at speeds greater than 60 kt.

calm.

westerly.

easterly

23. Statistical pressure values tend to be

on average parallel to the lines of latitude

higher over the oceans in winter

on average parallel to the lines of latitude in the southern hemisphere and much more variable in the northern hemisphere

much lower in winter in the northern hemisphere than in the southern hemisphere

24. The heat equator is

coincident with the equatorial trough and ITCZ

a line over the land joining places where the summer temperatures are highest.

another name for the geographic equator

a line over the land joining places where the winter temperatures are highest.

25. The most notorious advection fogs occur

over central North America in autumn and winter

over the sea in the region of Newfoundland and the Kamchatka peninsula

over southwest UK

over Europe with high pressure to the north

Question Bank

Questions for GLOBAL CLIMATOLOGY