Climate change

• Evidence of climate change:

  • Tree rings - each rings represents a year of growth, so wide ring = warm and lots of growth
  • Ice cores - ice is drilled and samples are collected, layers of snowfall are able to trap oxygen, which can be used to estimate temperatures
  • Melting ice
  • Sea level rise
  • Seasonal change - for example birds nesting earlier
  • Temperature records
• Natural causes of climate change:

  • Orbital change
  • Volcanic activity
  • Solar output
• Human causes of climate change:

  • Fossil fuels
  • Agriculture
  • Deforestation
• Orbital change as a cause of climate change:

  ~Milutin Milankovich was a Serbian Geophysicist and astronomer who came up when these theories:

  1. Eccentricity

  • earths orbit isn't fixed
  • changes from circular to ellipse every 100,000 years
  • closer to sun = hotter

  2. Axial Tilt

  • earth spins on axis, normally is 23.5 degrees
  • this can change from 21.5 to 24.5 degrees, every 41,000 years
  • closer to sun = hotter

  3. Precession

  • earth wobbles a bit
  • this cycle takes 26,000 years
• Impacts of climate change:

  ~Environmental impacts~

  • Sea level rise
  • Habitat destruction
  • Extreme weather

  
  

  ~Social impacts~

  • Health (heatstroke & more malaria - as there will be more breeding ground for mosquitoes)
  • Water & Food shortages
  • Migration
• Ways to mitigate (stop the cuase) climate change:

  • Alternative energy
  • Carbon capture
  • Planting trees
  • International agreements
• Ways to adapt to climate change:

  • Managing water supply
  • Change in agriculture systems
  • Reducing risk from rising sea levels (mangroves, house of stilts, seawalls)