Climate and Change Flashcards
Name all the natural causes of climate change
1)Eruption theory
2)Meteors
3)Changes in solar output
4)Circle to ellipse
5)Axis theory
6)Wobble theory
(Milankovitch cycles^^ 4-6)
How does eruption theory work, how long does it last and the effect on the earths climate?
- Volcano erupts and sends particles into the stratosphere, aerosols reflect solar energy back into atmosphere, ash blocks out sun
- Can last days, months or years
- Mountain in Philippines in 1991 released 10km3 of ash and cooled the world by 0.4 degrees
How do meteors work, how long does it last and the effect on the earths climate?
- Large meteors crash into earth and trigger natural disasters, total extinction
- Extremely random and rare
- When the dinosaurs became extinct
How do sun spots work, how long does it last and the effect on the earths climate?
- Higher number of sunspots, hotter earth is
- Most active over last 60 years out of 1150 year period
- 1645 & 1715, fewer sunspots seen and links to mini ice age
How does circle- ellipse cycle work, how long does it last and the effect on the earths climate?
- Earths orbit changes shape, circle to ellipse, varies sun exposure
- Changes shape every 100,000 years
- Changes earths temp by 5-8 degrees, start or end an ice age
How does axis theory work, how long does it last and the effect on the earths climate?
- Earths axis tilts, varies sun light exposure
- 41,000 years to switch from straight to tilt
- Changes earths temp by 2-3 degrees
How does wobble theory work, how long does it last and the effect on the earths climate?
- Spinning fast allows earth to stay straight, but slower and it wobbles
- 26,000 years to switch between wobble and straight
- Makes summers hotter or winters colder
What factors on the global and local have increased the emissions of greenhouse gases?
GLOBAL SCALE Fossil fuels being burnt Agriculture and growing demand for meat (like in Chinas developing middle class) Global trade LOCAL SCALE Domestic energy use growth Increased car driving
Facts about CO2
o From burning fossil fuels and deforestation
o Increased by 30% since 1850
o More power stations are used to meet energy needs, more cars used
Facts about methane
o From gas pipeline leaks, farming rice and cattle
o Increased by 250% since 1850
o Increased demand for agricultural meat and the retrieval of fossil fuels
How has the effects of climate change affected sea level rise?
Bangladesh
- By 2050, 15% of coasts will be underwater
- Thousands of people live in tents
- Broken embankments
- Thousands rely on charities
- Salty land
How has the effects of climate change affected crop yields?
- Egypt is predicted to lose 15% of wheat crops by 2050
- Increased temps by 4 degrees will cause 9 million more children to become malnourished by 2050 in South East Asia
- Food prices fall as better conditions for African crops so increased supply
How has the effects of climate change affected coral reefs?
Great Barrier Reef
- Flood on the coast cause polluted sea water from tourists
- 1500 fish species there that migrate to cooler water
- 360 hard coral species that become stressed and bleach in warm waters
- 22 species of shore bird starve when fish migrate
- Cyclones break up coral reefs
What are the arguments that natural causes are to blame for climate change?
₪ Some warming since 1979 but cause from urban heat island effect
₪ Global increase of 0.8 degrees since 1900
₪ Warming periods of earths history came 800 years before rise in CO2 levels
₪ After WW2, lots of CO2 was produced but global temps fell for 4 decades
What are the arguments that humans are to blame for climate change?
☯ Warmest period since 1997 is the last ten years
☯ Medieval warm period is patchy thus unreliable
☯ Arctic is at its warmest since last 2000 years
☯ Solar forcing cant be responsible as it doesn’t match greenhouse gases
