What is climate change?
is the long term change in the weather
Name the 2 evidence for climate change
- ice cores
- ocean sediment
Explain how ice cores shows the evidence for climate change
- Antarctic ice cores allows an understanding of long-term CC & the snow is undisturbed = no one lives there
- records go back to 800,000 years
- oxygen isotopes can be used to work out what the climate was for each layer of snow
Explain how ocean sediment shows the evidence for climate change
- organisms and remains of plankton reveal past water temperature + levels of oxygen
- the further the drilling = further back information about climate
What are the 3 natural causes of climate change?
- volcanic activity
- solar output
- orbital changes
Explain how volcanic activity can cause climate change
- particles can reflects the sun’s radiation away Earth , cooling it down = can be described as a volcanic winter(but it only last for few years & would cool the earth down)
- volcanic eruptions release CO2 = a GHG
EXAMPLE: 1991 eruption of Mount Pinatubo = global temperature to drop by 0.5 degrees for 4 weeks
Explain how solar output can cause climate change
- output of the sun is measured using sunspots -which are dark patches that develop on the sun’s surface
- sun output has had limited change in the last 50 years
Explain how orbital changes can cause climate change
this is the milankovitch cycles when:
- further from the sun = the cooler it is
- greater tilt = more extreme seasons
- wobble = seasonal changes
What are the 3 human causes of climate change?
- burning fossil fuels
- farming
- deforestation
Explain how burning fossil fuels can cause climate change
- co2 is released into the atmosphere when fossil fuels like coal, oil natural gas & are burnt e.g: in thermal power stations or cars
- account for 50% of GHG emissions.
Explain how farming can cause climate change
- farming livestock produces alot of methane = cows burps
- rice paddies contribute to global warming = flooded fields emits methane
- 20% contribution
Explain how deforestation can cause climate change
- plants remove co2 from atmosphere & converts it into organic matter via photosynthesis
- when trees are cut down = a decline in trees taking co2 in
- co2 also released into the atmosphere when trees are burnt as fuel/ to make way for agriculture
What does mitigation strategies do?
aim to reduce the causes of climate change by reducing the concentration of GHG in the atmosphere
List 3 mitigation strategies for climate change
- alternative energy produce
- carbon capture
- planting trees
Explain how alternative energy produce can mitigate climate change
- replacing fossil fuels with nuclear or renewable energy = helps reduces GHG emission with a reduction in burning fossil fuels
Explain how carbon capture can mitigate climate change
- carbon capture & storage (ccs) is designed to reduce emission from power station burning fossil fuels
- ccs provided a 50% reduction of carbon emission up to 2100
- ccs involves the capture and transport of co2 to a safe place to be stored
Explain how planting trees can mitigate climate change
- increase the amount co2 that is absorbed from the atmosphere via photosynthesis
- US $40 billion investment given = increase forest carbon storage by 28%
What is adaptation?
the response to the effects of climate change
What are 3 adaptation for climate change?
- changing in agricultural system
- managing water supply
- reducing risk from sea levels
How to change agricultural system to adapt to climate change?
- moving production to another country where the temperature is more suited
- increase water supply to irrigate (water) crops
- changing the time that crops are grown
How to manage water supply to adapt to climate change?
- reduce water demand
- recycle water
- increase supply through desalination
How to reduce the risk from the sea levels to adapt to climate change?
- London is protected by Thames barrier & has been closed 100 times since it was built
- but not all places can afforded expensive strategies like this
