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GRADE 10 SCIENCE:       MORE WEATHER REVIEW-- ANSWERS

 

NAME: _____________

 

  1. What is the definition of “prevailing wind?”

 

 

Winds which mainly blow in a constant direction, over large areas of the globe (within certain “bands” of latitude.)

 

 

 

  1. Explain why “high pressure areas” and “low pressure areas” exist over different parts of the Earth.

 

High pressure areas exist in cold areas such as the poles,        low pressure areas exist in hot areas like the equator

 

 

 

 

  1. What is the main reason that prevailing winds are created?

 

 

 

Air flowing from high pressure (cold) areas to low pressure (warm) areas

 

 

 

  1. What is special about the dates:  December 21st, March 21st , June 21st  and September 23rd.

 

 

 

Winter solstice (sun over tropic of Capricorn), equinox (equator), summer solistice (sun over tropid of cancer, equinox

 

 

 

  1. Why do seasons exist as they do in the Northern and Southern hemispheres?

 

 

The Earth is tilted about 23 degrees on its axis.  During summer, the Northern Hemisphere is tilted towards the sun:  sun’s rays are more direct.

 

 

 

 

    

  1. What is the definition of an “ocean current”?

 

Large masses of ocean water which mainly move in one direction, although some variations which exist

 

 

 

 

 

  1. List four factors which cause ocean currents to be created?

 

-temperature variation

-variations in salinity (fresh vs salt water)

-pull of gravity from the moon

-rotation of the earth (affect direction)

-____________

 

 

 

 

 

  1. List four ways in which the acid rain problem can be improved?

 

 

-burn less gasoline, fossil fuels

-use sulphur-reduced fuels

-use “scrubbers” to clean up pollution

-liming of lakes

-using catalytic converters to convert NOx in car exhaust to nitrogen

 

 

 

  1. Why is weather prediction so difficult (or impossible) to get perfect?

 

 

TOO MANY VARIABLES

 

  1. Tornados:

 

                                                               i.      What conditions are necessary for tornados to occur?

                                                             ii.      What is the main ‘tornado season?’

                                                            iii.      Where do most of the world’s tornados occur?

 

 

Hot temperatures, turbulent weather conditions, cumulonimbus clouds, a warm front meeting a cold front

 

Spring time  (may – july) in central midwest

 

 

  1. What is the impact on the shrinking polar ice caps (at both poles) on the overall trend of global warming?

 

Increases temperature absorption by Earth and atmosphere because less solar radiation is reflected by the ice and snow