Climate Change

• Finish the sentence: Climate change is the result of ....

  natural and human factors and has a range of effects.
• what is the quaternary period?

  the last 2.6 million years. the most recent geological time period.
• what is evidence for climate change during the quaternary period.

  1) using burried fossils and layers of sediment which preserve global temperatures of the time they are from.

  
  

  2) Scientists then calculate the oxygen or CO2 levels as well as the composition of the water.

  
  

  3) Our climate has been warming rapidly. Average (global) air temperatures have risen by 0.85 since 1880, mostly in the 1970s.
• what is recent evidence for climate change?

  shrinking glaciers and melting ice caps, rising sea levels, seasonal changes
• what are the global effects of climate change?

  1) ice caps shrinking, benefits ships in the future giving them more access. but harms arctic wildlife such as polarbears.

  
  

  2) low lying Pacific Islands such as the maldives are at risk of sea level rise which leads to flooding.
• what are natural causes of climate change?

  Orbital changes, volcanic activity and solar output
• what are human causes of climate change?

  The greenhouse effect which can be enhanced in several ways such as burning fossil fuels.
• what ate inter glacial periods?

  the warmer periods between glacial periods
• how is melting ice evidence for climate change?

  arctic sea ice thinned by 65% since 1975. glaciers are retreating and some may completely disappear by 2025.
• how is rising sea level evidence for climate change?

  average global sea level has risen by 10-20cm in 100 years. this is due to:

  
  

  1) Glaciers: ice melting provides more water.

  
  

  2) thermal expansion: oceans warming causes water to expand.
• how are seasonal changes evidence for climate change?

  seasonal activities are happening earlier such as bird migration.
• what are glacial periods?

  when ice covered parts of Europe and North America.
• What are Milankovitch cycles?


  eccentricity, axial tilt, and precession. the three cycles all affect the world's climate and seasons.
• How do orbital changes prove climate change?

  eccentricity is the main factor as the orbir is not fixed and changes from almost circular to slightly elliptically. This changes the distance from the sun. the glacial period is further from the earth.
• How does solar output prove climate change?

  sunspots are dark patches on the sun. there are 11 year long sunspot cycles in which the number of sunspots increase from minimum to maximum then back to minimum. the minimum is the lowest solar output and leads to cooler temperatures.
• How does volcanic activity prove climate change.

  volcanic eruptions lead to lots of ash in the atmosphere and clouds of ash, blocking sunlight. this temporarily lowers temperature. SO2 emissions cause droplets of sulfuric acid to reflect radiation. This cools the area for 2-3 years.
• what is the greenhouse effect?

  the atmosphere allows short wave radiation to pass through, this warms the earth surface. When the earth warms it gives off long wave radiation which is absorbed by gases.
• what does the atmosphere contain?

  particles such as dust, gases such as nitrogen, liquids such as water.
• why is the greenhouse effect important?

  it keeps the earth habitable and warm enough.
• what is the enhanced greenhouse effect?

  human activities producing more greenhouse gas.
• what greenhouse gases are we producing?

  nitrous oxides, carbon dioxide, methane.
• how are we producing Nitrous oxide and how much of it is in the atmosphere?

  very small amounts, from car exhausts, fertilisers, sewage treatment, power stations.
• how are we producing carbon dioxide and how much of it is in the atmosphere?

  60% of the enhanced greenhouse effect. burning fossil fuels for electricity, car exhausts, deforestation.
• how are we producing Methane and how much of it is in the atmosphere?

  20% of the enhanced greenhouse effect. Organic matter decaying in landfills, rice farming, livestock, burning biomass.
• what are the ways to manage climate change?

  mitigation and adaptation
• what is mitigation

  reducing causes.
• What are the ways to mitigate climate change?

  1) alternative energy source.

  
  

  2) carbon capture

  
  

  3) planting trees

  
  

  4) international agreements
• how does using an alternative energy production mitigate climate change?

  using renewable energy such as solar and hydroelectricity can be used for a longer period of time without enhancing the greenhouse gas effect. Nuclear reactors are already being built in Somerset.
• how does planting trees mitigate climate change?

  trees are carbon sinks and remove CO2. they release moisture which results in the cooling of the atmosphere. plantation forests can absorb CO2 faster and more effectively for 50 years.
• how do international agreements mitigate climate change?

  global solutions such as the 2015 Paris Agreement. a deal with 195 countries. balance the sources and sinks of greenhouse gas to limit global warming below 2 degrees. COP 26 also has new targets for CO2 emissions to improve energy efficiency and promote renewable energy.
• what is adapting to climate change?

  responding to changes.
• how does carbon capture mitigate climate change?

  CCS can capture 90% of CO2 before it enters the atmosphere. it is compressed and transported to the water which is injected by a pipeline into the ground to store it in reservoirs.

  
• what are the ways of adapting to climate change?

  1) change in agricultural systems.

  
  

  2) managing water supply.

  
  

  3) reducing risk of rising sea levels.

  
  

  4) flood barriers
• how does a change in agricultural systems help adapt to climate change?

  farmers should be educated and produce drought resistant crops but also shade trees from very strong sun rays. new crop patterns and irrigation methods can be introduced. rainfall will fluctuate along with a rise in temperature.
• how does managing water supply help adapt to climate change?

  rainfall is unreliable so rural areas will be strongly impacted. In the Himalayas millions of people depend on rivers and glaciers for water supply. GM crops can increase yield by 6-25%.
• how does reducing risk of rising sea levels. help adapt to climate change?

  this reduces coastal erosion and protects areas from storm damage. Small Islands such as the Maldives are at the most risk. sea walls, elevated artificial islands and houses helps. People may need to be relocated as the future is uncertain.
• how do barriers help adapt to climate change?

  In Italy, barriers are connected by canals. Mobile barriers, 78 gates block tides.
• global impacts of climate change?

  strong tropical storms and increased risk of natural hazards.

  
  

  rising sea levels

  
  

  lower crop yield

  
  

  desertification

  
  

  affects food production and water supply
• what is drip irrigation?

  water dripped slowly to plants through a tube.