Climate Change Flashcards
What are 3 natural causes of climate change?
Orbital changes
Solar output
Volcanic acitivy
How do orbital changes lead to climate change?
Sun’s eclipse changes every 100,000 years
Orbits closer to sun; warmer climate
Tilt increases; exaggerates climate
How does volcanic activity lead to climate change?
Sulphur mixes with water vapour
Becomes volcanic aerosol
Reflects suns heat energy entering atmosphere
Global temps drop
How does solar output lead to climate change?
Sunspots caused my magnetic activity inside sun
Fluctuations in amount of radiation from sun
Solar output measured by sunspots
What are 3 human causes of climate change?
Fossil fuels
Agriculture
Deforestation
How do fossil fuels lead to climate change?
Over 50% of GG emissions- releases CO2
Greenhouse effect; sun’s rays let into atmosphere but not back out
Used for transportation, heating, building
How does agriculture lead to climate change?
20% of GG emissions- produce methane
Cattle produce it during digestion
Population increases- for food required
How does deforestation lead to climate change?
Photosynthesis; trees absorb CO2 and release O2
Fewer trees can absorb or, and CO2 is released back into atmosphere when cut down
What are 3 long term evidences of climate change?
Ice cores
Tree rings
Ocean sediments
What do ice cores show about climate change?
Layers of ice build up over thousands of years
Ice cores drilled out
Trapped CO2 and methane released- compared to present levels
What do tree rings show about climate change?
Natural recorder- used before reliable data methods
Only indicate change rather than specific temperatures
E.g rings grow wider in warm, wet years and thinner in cold and dry years
What do ocean sediments show about climate change?
Deeper the sediment, older it is
Billions of tonnes deposited- provide timeline
Organisms reveal past surface temps and oxygen levels
What are 2 recent evidences of climate change?
Melting ice
Seasonal changes
What does melting ice show about climate change?
Ice sheets melting; sea levels rise
Risen by 19cm since 1900
What do seasonal changes show about climate change?
Seasonality variations
Plants and animals starting to adapt
What are 2 economic effects of climate change?
Cost of adapting coastal areas to rising sea levels
Loss of capacity to work- either sever heat or diseases spread due to higher temps
What are 2 environmental effects of climate change?
Shrinking productivity of harvests- too hot, not enough rain, too wet- destroy them
Species extinctions- tigers; forest fires. Snow leopards; snow, ice melting
What are 2 social effects of climate change?
Increased floods due to rising sea levels- loss of income from tourism
Skin cancer e.t.c- death toll increases, greater fees on healthcare
What are 2 mitigation strategies?
Solar energy
International agreements
What is 1 advantage and 1 disadvantage of solar energy?
- Saves over a ton of CO2- not GG emission to contribute to climate change
- No sunshine at night- cannot be relied on to generate electricity
What is one advantage and one disadvantage of international agreements?
- Makes a good difference- global emissions reduced by 60% by 2050
- Challenge for countries to agree on targets- some can afford mitigation more than others
What are 2 adaptation strategies?
Changes in agricultural systems
Managing water supply
What is 1 advantage and 1 disadvantage of changes in agricultural systems?
- Farmers and families continue to make income and eat crops they grow
- Cost of adapting is harder for poorer subsistence farmers
What is 1 advantage and 1 disadvantage of managing water supply?
- Summers wont get dryer and winter wont get wetter; water supply being controlled
- Desalination plant requires lots of energy- CO2 emissions need to be offset by an electricity plant
