The Restless Atmosphere - Ocean Currents, Air Masses, Gases Flashcards
Explain what type of current the Labrador current is
Cold current which flows from Greenland along north coast of America
Brings cold air with it and freezes many ports ( Canada, USA)
Brings icebergs into North Atlantic
Explain what type of current the North Atlantic Drift is
War, current which starts as the Gulf Stream. Flows north easterly from Gulf of Mexico to Western Europe
Raises temperatures and keeps ports ice free
Ensures rainfall throughout the year
Explain what type of current the canaries current is
Cold current flowing south along the west coast of Africa. Very little moisture in wind so brings very little moisture to the Sahara.
What direction do the currents of the North Atlantic flow
A clockwise direction
Explain air mass
A body of air with its own temperature pressure and humidity level. They effect the weather of the countries they pass over.
Name the four air masses over Ireland and describe the weather they bring.
Polar air masses - cold
Continental air masses - dry
Tropical air masses - warm
Maritime air masses - wet
Explain a front
A front is where two air masses meet. They do not mix very well because of their different temperature,pressure and humidity
Explain how a cold front forms
A cold front forms when a cold air mass moves in towards a warm air mass. The cold air forces the warm air to rise
As the warm air rises it cools and condensation occurs.
Clouds are formed and this leads to rainfall
Explain how a warm front is formed
A warm front develops when warm air moves towards cold air. The warm air rises above the cold air
Condensation occurs as the warm air cools and clouds are formed which brings rainfall.
Explain depression
A depression is an area of low atmospheric pressure also known as cyclones
Often pass over Ireland and bring wet and windy conditions.
Describe how a depression forms over Ireland
A cold air mass (polar) meets with a warm air mass(tropical) and they do not mix as they have different temperatures, humidity,and pressure
Due to friction the warm air just into the cold air and makes a dent. Warm air rises creating area of low pressure and cold air comes from behind replacing warm risen air. Cold front and warm front develop.
Winds swirl around low pressure centre, the cold front constantly trying to catch up with the warm front.
Explain anticyclone and the weather they bring
An anticyclone is an area of high pressure, anticyclones bring clear sunny weather. There are few clouds and gentle breeze
Explain the greenhouse effect
Occurs naturally
The sun Heats up the earth and some heat gets trapped in gases in the atmosphere so heat is contained on earth
Without greenhouse effect it would be too cold for us to live on the earth
Explain global warming
Carbon dioxide and methane are two greenhouse gases in the atmosphere. The amount of these gases has increased a lot and this causes more of the sound heat to be trapped on earth. This makes the earth warmer and this is called global warming
Give causes of global warming
Increase in CO2 in atmosphere
People burning more fossil fuels
Tropical rainforests being cut down and so less trees absorbing CO2
More CFCs I. The atmosphere. These are bad gases which trap the Suns heat
