challenges for the planet 1 Flashcards
what are the human causes of climate change
cars and transport = pollution
greenhouse gasses by fossil fuels
increase in energy consumption
natural cause of climate change
cows and methane
volcano and sulphur
solar output (heat trapped)
increase in methane
china = more rice and more cow
more disposable income means meat is demanded
negative effects of climate change
changing pattern of crop yield e.g. Tanzania and Mozambique e.g. droughts
treating glaciers = loss of habitat
Labrador, Atlantic = 8-10 degrees in july.
90% of glaciers in Antarctic are retreating
rising sea levels = flooding in coastal areas.
1993-2006 = 3.3mm global increase
London, Tokyo, NYC = low lying = flooding
how companies/the government promote sustainability
park and ride in Cambridge (public transport)
£2.20 per ticket
advantages:
cheap
convenient reduces traffic
busses every 10mins
disadvantage
expensive start up
bus congestion
unreliable / late
how has the climate changed since the last ice age?
8000BC was end of ice age, and world temp has risen 6 degrees C since.
temp change of 5 degrees over next 2000 years then
decrease of 1.5 degrees in 5000 BC
next 1500 years = increase and second warm period.
between 2000BC and 2000AD was the medevil warm
period - temp change of 1 degree
mini ice age.
projected temp to increase by 5 degrees by 2100
what are the external and internal factors affecting climate change?
external:
solar output
orbital geometry
internal:
volcanic activity
surface relfection
tectonic activity
explain solar output (external factor)
it is the energy that comes from the sun
more solar output means hotter and less means cooler. a 1% change in solar output could make temp rise or fall by 0.5-1 degree C.
in 1980s the amount reaching earth decreased by 0.1%.
sunspots affect solar output. reduced sunspot between 1645 and 1715 may of caused mini ice age
orbital geometry (external factors)
orbital characteristics that are responsible for the past and possible future climate changes
1) shape of the earth orbit around the varies from nearly circular to elliptical and back to circular again every 95000 years.
circular = cold and glacier
elliptical = warmer
2) the tilt of the Earth’s axis varies from 21.5 and 24.5 degrees. this occurs over a 41000 years.
greater angle= hotter summers & colder winters. also usually warm periods
volcanic activity (internal factors)
volcanic eruptions releasing gas and ash
lots of sulphur dioxide and ash is released. reduces amount of solar radiation reaching the earth = cold.
1815) mount tambora erupted meaning Europe had lots of snow and world was unusually cold. “year without summer”
surface refection (internal factor)
snow and ice reflects sun into space
cooler periods = snow and ice. global temp drops because it reflects sunlight back into space.
if planet warms then the snow will melt and earth temp will increase
tectonic activity (internal factors)
movement of continents caused by plate tectonics
affects global patterns of atmospheric and ocean circulation.
causes winds and ocean currents to change.
process is to slow to have effect on climate over 10,000 yrs
change in atmospheric gas
CO2 = largely responsible for the greenhouse gas effect. it traps heat by absorbing longwave radiation
without it the world would be at -18, rather than +15 degrees
causes on climate change on a local scale
cars = pollution = greenhouse
methane and C02. methane is 20 times more potent than CO2 and makes up for 20% of the green house.
energy consumptions e.g. fossil fuels
causes to climate change on a global scale
75% of china energy = coal. = fossil fuels and greenhouse
fossil methane (30% methane) is released when we mine for fossil fuels
