mock exam Flashcards
How has the climate changed during the Quaternary period
Fluctuated but more recently has increased and is now 1.2 degrees celsius above pre-industrial levels
what is the evidence for the climate changing during the quantinary period
Ice cores
Tree rings
Diaries
Old paintings of the Thames
What is the carbon cycle?
The transfer of carbon between the atmosphere and biosphere via the natural processes of photosynthesis and respiration.
Humans also add to this cycle by burning fossil fuels in cars, power stations etc.
What is the greenhouse effect?
Shortwave radiation heats the surface of the earth
The earth then radiates this heat out as longwave radiation
Some of this heat is trapped by a layer of greenhouse gases e.g. carbon dioxide.
Some of the heat escapes
What are the natural causes of climate change?
Orbital theory - the earth wobbles on its axis and is sometimes closer to the sun
Volcanic theory - ash blocks out sun reducing heat
Sunspot theory - areas of intense activity
What are the human causes of climate change?
Burning of fossil fuels in power stations and cars
Methane from cows
How does global circulation create areas of low and high pressure?
Over the Equator intense heat causes the air to evaporate and rise at the ITCZ
As it rises, it cools and condenses creating an area of low pressure
It then rains over the Equator
The air then moves north and south and sinks due to it being cold
It sinks over the Tropics of Cancer and Capricorn
As it sinks it warms up, therefore condensation does not take place, and therefore there are no clouds.
This creates an area of high pressure
What is the distribution of areas affected by hurricanes/cyclones and how does this change over time?
They are found over the Equator
They move west and in the northern hemisphere they turn to the right and in the southern hemisphere they turn to the left
This is due to the Coriolis effect - the spinning of the earth
What are the causes and consequences for people, environment and economy of one located low pressure hazard?
Cyclone Pam
-Category 5 storm, wind speeds up to 155mph, peaking at 168mph
-11 people did
-90,000 made homeless
-80% of subsistence crops destroyed
-Coastal areas flooded
What are the responses to one located low pressure hazard?
-Emergency aid sent by Australia, Fiji, France, New Zealand and UK
-Repairs provided safe drinking water
-Blankets distributed
-153 temporary schools set up
-Foreign medical teams arrived
What is the location of areas affected by heatwaves and droughts
Along the tropics of Cancer and Capricorn
What is the location of areas affected by heatwaves and droughts and how does this vary over time?
he position of the Jet Stream determines where these droughts take place
It pushes the rains, particularly in the winter over California however in recent years this has not been happening.
What are the causes for people, environment and economy of one located high pressure hazard?
california drought
Causes
Low winter rainfall and not much in summer
High pressure remained stationary over California
2012-2015 - low air pressure pushed away due to jet stream
What are the consequences for people, environment and economy of one located high pressure hazard?
california drought
Consequences
Low river levels meant no hydroelectric power
Crop failure led to shortages and price rises
17,000 agricultural jobs lost
Salmon and trout died as river levels fell
Groundwater not recharged
What are the responses to one located high pressure hazard?
california drought
Compulsory water restrictions including ban on watering gardens/cars
Toilets, washing machines etc must use low water technologies
Reduction in electricity produced by hydroelectricity
Investment into desalination plants
Growing crops that don’t need so much water
What is the difference between weather and climate?
Weather is day to day changes in the atmosphere
Climate is the average conditions over a longer period of time normally 30 years.
How does climate vary in the UK?
The North of the UK is colder then the south
The West of the UK is wetter than the East.
factors that affect temperature and rainfall in the UK
lattitude
altitude
aspect
ocean currents
what is latitude
the earth’s rays are more concentrated the closer you are to the Equator therefore the warmer it is the further south you go.