write up Flashcards
what were management strategies to reduce the risk of Boscastle flood happening again?
- £4.5 million has been spent on flood defence scheme
- river channel has been made deeper and wider to hold more water
- Boscastle car park has been raised + given a permeable surface
what is the quaternary period?
- most recent geological time period
- period of time from 2.6 million years ago to present day
what was the period before the quaternary like?
earths climate warmer + quite stable
how did things change in quaternary?
- during quaternary global temp had shifted between:
- cold glacial periods that last around 100,000 years
- and warmer interglacial periods that last around 10,000 years
when did the last glacial period end?
around 15,000 years ago - since then climate has been warming
how are ice cores evidence for climate change?
- scientists often use ice cores to detect changes in temp
- by analysing gases trapped in layers of ice can tell what temp was each year
how are early springs evidence for climate change?
- in recent years have been signs of seasonal shift - spring arrives earlier + winters tend to be less severe
- these seasonal changes affect the resting + migration patterns in wildlife
how is pollen analysis evidence for climate change?
- pollen from plants get preserved in sediment
- scientists can identify + date preserved pollen to show which species were living at the time
how are tree rings evidence for climate change?
- scientists take the cores of trees + count rings to find the age of tree
- thickness of each ring shows what the climate was like
- reliable source of evidence of climate change for the past 10,000 years
what do orbital changes affect?
- affect how much solar radiation the earth receives
- more energy means more warming
what are the variations of how the earth orbits?
- stretch - the earth’s orbit around the sun varies from circular to elliptical - called eccentricity
- tilt - earths axis is tilted at an angle as it orbits the sun
- wobble - earths axis wobbles
how is volcanic activity a possible factor for climate change?
- during a volcanic eruption carbon dioxide is released into the atmosphere
- volcanic activity may also cause short term changes to the climate
how is solar output a possible cause of climate change?
- there can be fluctuations in the amount of radiation from the sun
- reduced solar output means that the earth’s climate may become cooler in some areas
- solar output isn’t thought to have a global effect on climate change
how can cement production be a possible cause?
- cement is made from limestone - which contains carbon
- when cement is produced - lots of co2 released into atmosphere
what else can be a possible cause of climate change?
- greenhouse effect
- burning of fossil fuels
- farming
- deforestation
what effects does climate change have on the environment?
- sea levels are rising due to land ice melting
- sea ice shrinking leading to loss of polar habitats
- precipitation patterns changing
how can biodiversity decrease as a result of climate change?
- some species now live at higher latitudes due to warming temperatures
- some habitats destroyed or damaged - species can become extinct
how can climate change affect people?
- in some places deaths due to heat have increased
- some areas could become so hot + dry - difficult/ impossible to inhibit
- in some areas - problems with water availability caused by changing rainfall patterns
how is climate change affecting farmers?
- globally some crops have suffered from climate change resulting in smaller yields
- this could increase malnutrition, illness and death from starvation
what does climate change mean for the weather?
- means weather getting more extreme
- means more money has to be spent on predicting extreme weather - reducing their impacts + rebuilding after they take place
how is planting trees a good mitigation strategy to reduce causes of climate change?
more co2 absorbed from atmosphere through photsynthesis
how is carbon capture a good mitigation strategy to reduce causes of climate change?
- carbon capture and storage is designed to reduce emissions from power stations burning fossil fuels
- involves capturing co2 + transporting it to safe places where it can be stored
how is alternative energy production a good mitigation strategy to reduce causes of climate change?
replacing fossil fuels with nuclear or renewable energy can help reduce greenhouse gas emissions
how are international agreements a good mitigation strategy to reduce causes of climate change?
- in 2005, the Kyoto protocol became international law
- the countries that signed up to the treaty pledged to reduce their carbon emissions by 5%
- but overall impacts had been small
- the US refused to join + major developing countries like China + India were not required to make any reductions
how is changing agricultural systems a good adaptation strategy?
- may be necessary to plant new crop types that are more suited to the new climate
- some regions - biotechnology is being used to create new crop varieties resistant to extreme weather events
how is managing water supply a good adaptation strategy?
- water meters can be installed in homes to discourage excessive water use
- rainwater + wastewater can be collected and recycled
how is coping with rising sea levels a good adaptation strategy?
- better flood warning systems are being put in place + physical defences such as flood barriers are being built
- in areas that can’t afford expensive flood defences people are building raised flood shelters
