The weather and the climate Flashcards
Explain the greenhouse effect?
The sun produces short wave energy which goes through the atmosphere and heats the Earth’s surface
● The Earth’s surface returns long wave energy
● However, the long wave energy finds it difficult to pass through certain gases
● Therefore, some heat is trapped within the atmosphere
List 3 greenhouse gasses
● Methane
● Carbon dioxide
● CFCs
List 3 human activities that cause global warming
Fossil fuels
Burning fossil fuels e.g coal, oil and gas, releases carbon dioxide into air
Trees cut down
Less trees are present to absorb carbon dioxide. This results in more carbon dioxide in the air
Household waste
Refuse dumps containing waste emits methane
Plastics and fridges
CFCs produced when making plastics and fridges
List the effects of global warming
Sea levels rise
● Polar ice caps melt
● Desertification
● More severe weather conditions
What can we do to stop global warming?
Use renewable energy
● Plant more trees
● Conserve energy
How does wind occur?
Unequal heating of the Earth at different latitudes
● Air has atmospheric pressure
● Cold air is dense and heavy, creating an area of high pressure
● Warm air is not dense and is light, creating an area of low pressure
● Winds blow from areas of high pressure to areas of low pressure
List the different types of winds
Prevailing winds are the most common winds in an area Warm winds blow from the equator
Cold winds blow towards the equator
Winds are named from the direction where they blow
What is the Coriolis force?
Earth rotates on its axis from west to east
● Winds in the northern hemisphere deflect to the right
● Winds in the southern hemisphere deflect to the left
What are the effects of ocean currents, warm currents and cold currents of the air and sea?
Ocean Currents ● Great heat at low latitudes causes water to expand and becoming less dense ● Cold conditions at high latitudes have the opposite effect ● Global winds drag ocean currents Effects of warm currents ● Raise sea temperature ● Raise air temperature ● Prevents harbours from freezing Effects of cold currents ● Lower sea temperature ● Lower air temperature ● Increase possibility of ice
Ireland and the North Atlantic Drift
Heats the waters off our coast
● Prevents Irish harbours from freezing in the winter
● Transfers winter warmth to the southwesterly winds which prevail over Ireland ● Keeps our winters more milder
Explain weather and climate
Weather is the condition of the atmosphere over a very short period of time
Climate is the condition of the atmosphere across a large area of the Earth’s surface and over a very long period of time
What are depressions (weather)
Depressions ● Areas of low pressure ● Cyclones or lows ● Oval in shape ● Pressure is lowest at the centre
What are anticyclones?
Areas of high pressure ● Highs ● Roughly oval in shape ● Larger than depressions ● Pressure is highest at the centre
What is a Stevenson screen?
Painted white to reflect sunrays from the box
● Slatted sides allow air but not direct sunlight
● Contains a hygrometer
What is a wind vane?
Free moving arrow on high mast
● Tail is wide and blown forward by wind
● Arrow points direction from which wind blows
What is an Anemometer
Three cups rotate when the wind blows
● The stronger the wind blows, the faster they rotate
● The number of rotations is recorded on a meter
What is an aneroid barometer?
An aneroid barometer measures atmospheric pressure
● It consists of a hollow metal box with a vacuum
● Air enters the vacuum and a needle attached to the box indicates the pressure of the air
in the box
● Pressure is measured in millibars or hectopascals
● Isobars are the lines on a map that join places of equal pressure
What is a Campbell stokes recorder?
Measures hours of sunshine each day
● A solid ball
● Concentrate the sun’s rays onto a removable strip
● Rays scorch card
● Different parts are scorched as sun changes position
● Card is marked off in hours, so that the scorch marks reveal when and for how long the
sun is shining
What is a rain gauge?
Measures precipitation in mm
● Outer cylinder
● Partially buried in ground
● Spot away from buildings or trees
● Outer cylinder has a funnel directing water into a measuring cylinder
● Measuring cylinder shows rainfall in mm
What are isobars, isotherms, isohyets, isohels and isotachs?
Lines on weather maps
Isobars= pressure Isotherms= temperature Isohyets= precipitation Isohels= sunshine Isotachs= wind speed
Name 5 factors that affect climate
Latitude, distance from the sea, altitude, relief and prevailing winds
Explain the 5 factors of climate change
Latitude
● Refers to the distance from the equator
● Further a place is from the equator, the colder it will be
● Uneven distribution of heat
Distance from the seas and ocean
● The sea absorbs and loses heat slower than land
● Coastal lands are not too hot in summer/not too cold in winter
● Annual temperature range is small
● Temperate climate
● Land absorbs and loses heat quicker than sea
● Inland countries are hot in summer/cold in winter
● Annual temperature range is large
● Continental climate
Altitude
● Refers to the height above sea level
● The higher a place is, the cooler the climate will be
● For every 150m we climb, the temperature decreases by one degrees Celsius and this is
known as the lapse rate
● The higher we climb, the thinner the air will get and the less heat it will be able to retain
● High mountains are exposed to wind leading to further cooling and this is known as the
chill factor
Prevailing air masses or winds
● Northerly air masses are cool and dry
● Easterly winds are warm in summer, very cold in winter and dry
● Southerly air masses are warm and may bring rain
● South-westerly winds bring temperate conditions and bring rain
Relief
● Refers to the shape of the land’s surface
● Aspect refers to the direction in which the slope faces
● In the northern hemisphere, south facing slopes are usually warmer than the north facing
slopes
Explain the water cycle
Evaporation
● Condensation
● Precipitation
● Soakage and run off
What are the forms of water?
Water vapour
● Cloud
●Precipitation
What is water vapor?
Air holds moisture in the form of water vapour
● The amount of water vapour in air is expressed as Relative Humidity
● Warm air holds more water vapour compared to cold air
● When the Relative Humidity is 100%, the air is saturated and extra water vapour will
undergo condensation
● Tiny droplets form cloud
Name 3 different types of clouds
Cirrus ● High altitude ● Delicate brush strokes Cumulus ● Medium altitude ● Fluffy clouds ● Dark ones bring showers Stratus Clouds ● Low altitude ● Occur in thick layers ● Can bring long spells of precipitation
What is relief rainfall?
Moisture laden winds blow in from the sea
● Air rises over mountains and is cooled
● Water vapour condenses to form cloud and rain on the windward side of the mountain
● When the air moves down the leeward slope, it has already lost most of its moisture
● The leeward side gets little rain and a rain shadow area is formed
What is conventional rainfall?
The sun heats the Earth’s surface
● Air over the hot land is warmed
● The air expands and rises rapidly
● Water vapour condenses to form cumulus cloud and heavy, thundery showers
Cyclonic rainfall
Warm air is light so it tends to raise over heavier, cool air
● The warm air cools
● Water vapour condenses to form stratus cloud and rain occurs
What is weathering?
Weathering is the breakdown and decay of rocks that are exposed to the weather and waste material is not removed
What is erosion?
Erosion is the breaking down of rocks and the removal of the particles
Explain freeze thaw action
During the day, rainwater seeps into the cracks in mountains
● At night, the temperatures drop below 0 degrees Celsius and this causes the rainwater
the freeze and expand
● When water expands, it puts pressure on the rocks in the mountains
● Over time, pressure increases and the rocks fall to the bottom of the mountain
● The loose rocks are known as scree
Explain carbonation
Rain takes in carbon dioxide as it passes in the atmosphere
● Carbon dioxide mixes with rainwater, forming a weak c arbonic acid
● Weak acid reacts with limestone (which contains calcium carbonate) and slowly
dissolves it
The burren landscape (you don’t have to remember all just an overview)
Limestone pavement
● The large area of exposed limestone
● Weathered by carbonation
● Cracks in the limestone are widened and deepened forming g rikes (deep grooves)
● Blocks of limestone that remain are clints (blocks of limestone that remain)
2. Swallow holes
● Carbonation occurs when rivers flow on a bare limestone surface
● Water widens joints and bedding planes, opening them up
● The river disappears underground through a swallow hole
● The largest swallow hole in the Burren is Pollnagollum
3. Underground features of the Burren
● Carbonic acid in water dissolves limestone as the river flows underground, cutting long tunnels
● Some drops of water containing calcium carbonate hang from the roof while some evaporates
● As the water evaporates, it leaves behind deposits of c alcite
● Calcite slowly builds up to form stalactites o n the roofs of caves
