The Impacts of Global Warming Flashcards
what evidence & statistics is there to suggest that global warming is having a direct impact on the arctic?
- warming since 1950s at twice the rate as rest of world
- greenland ice sheet already melting, at 16% faster rate, in Disco Bay
- 50% arctic ice lost by 2100
- 10% decline in snow cover since 70s
how is the melting ice affecting the climate of North West Europe?
melting ice = arctic ocean more saline & warm
weaken formation of Arctic Conveyor
no warm water brought up by north atlantic drift current
what are the 4 environmental impacts that global warming has on the arctic?
- vegetation shifts
- thawing of permafrost
- increasing fires & insects
- marine species
what is a positive & negative impact of global warming affecting vegetation shifting in the arctic?
Positive: benefits arctic agriculture, longer growing seasons
negative: destabilises existing food webs
how does global warming make vegetation shift in the arctic?
makes it move northwards into tundra
how much permafrost is expected to thaw in sibria due to global warming?
40% expected to thaw, warmed by 2degrees since 70s, shift 100km north
give one positive & negative impact on permafrost melting in the arctic due to global warming
Positive: create new wetlands = species
Neg: release methane
what are the two negative impacts global warming has on insects & fires in the arctic?
- 80% increase in forest fires by 2100 = no carbon sinks from boreal forest in russia
- spruce bark beetle = eat spruce trees
what 3 species are negatively impacted by global warming in the arctic?
- polar bears & seals extinct
- geese different migration patterns
what are 2 negative soioeconomic impacts that global warming has on the arctic?
- inuit hunting culture lost & bad food security
2. arctic char freshwater fisheries decline
what are 4 positive socioeconomic impacts that global warming has on the arctic?
- arrival of cod & herring fish, more saline water
- more access of marine shipping, less glaciers
- enhanced agriculture & forests, less snow
- new land exposed used for oil & gas drilling = money
why is africa being affected by global warming unfair?
contribute least to global warming but suffer the most, predicted 5deg increase faster that rest of global increase
name the 6 main direct impacts that global warming has on africa
- water issues
- food insecurity
- natural resources
- health
- development of coastal zones
- desertification
how could global warming affect conflict over water in africa?
- demand for water already outweighs supply for 25% of africans
- river nile internationally shared, conflict & wars over water, people migrating away & famine
why is the impact from global warming on water resources predicted to be worse in the north & south of africa?
rainfall will increase due to inter tropical convergence zone in equatorial area, depriving north & south
how is food security going to be threatened as a result of global warming in africa?
water dries up = no crops/ eaten by locusts => 70% pop of subsistence famers starve
how will lack of natural resources due to global warming affect people in africa?
- no biodiversity
- poor who depend on wildlife starve
- kenya looses safari tourism income as ‘big five’ species die out
- 80% remedies rely on plants that will die
how is health in africa threatened by global warming?
more water bourne diseases, malaria & diarrhoea = more medical expenses
plant species that make 80% remedies extinct = more deaths
how do developed coastal areas in africa make it more vulnerable to indirect impacts of global warming?
- 60% africa live on coast
- environmental refugees & shanty town cities Lagos & Freetown = unstable infrastructure
- more vulnerable to sea level rise & flooding
explain how global warming impacts desertification in africa
- areas of no grassland, The Sahel
- unfertile land, destroyed due to drought & marginal farming
- drought caused by unreliable rainfall
how much is sea level expected to rise by in 2100?
15 metres!
which 4 things contribute to the predicted rise of sea level by 15m, by 2100?
- largest to smallest*
1. 7m rise: greenland ice sheet
2. 5m: west antarctic ice sheet
3. 2m: worlds glacier systems
4. 1m: thermal expansion
why is it difficult to predict eustatic sea-level rise in the future?
- unknown how many GHG emitted
- model might become sustainable from tipping point or follow present patterns
- hard to predict impact of thermal expansion and glaciers melting
even if we stabilised the amount of GHG emitted, why might this not reduce sea-level rise?
- continued warming of deep oceans due to more sunlight let in through gaps in ozone
- sea level may continue to rise in some places because of local land movements and isostatic change
which 3 areas are most vulnerable to sea-level rise (with specific examples)?
- large river deltas (Nile/Mississippi)
- areas close to sea level & already defended (netherlands)
- low-lying islands (maldives/Philippines)
geophysically, why is bangladesh vulnerable to sea-level rise?
- coast is too long to defend
- 70% of country only 6m above sea level = flooding
- vulnerable to typhoons & storm surges
what are humans doing in bangladesh to make them more vulnerable to sea-level rise?
- destroying mangrove swamps
- rapidly growing population
- 65% of pop subsistence farmers
how is sea level rise predicted to impact bangladesh in the future?
- lose 20% of land = displace 40 million
- lose agricultural land, food supplies and fresh water
- 2025: local sea (isostatic) level rise by 1m
how will sea level rise impact a HIC?
The Netherlands
- 50% of land already reclaimed from sea
- densely populated and developed
- defended by dykes and coastal sand dunes
- 1m rise in sea level would code $12,000 million to defend
why are the pacific islands in general so vulnerable to sea level rise?
- difficult to reach/flee, remote
- hurricane prone
- dense, rapid urbanisation on Fiji
- limited resources, some of least developed countries in world
how has/will sea-level rise impacted Tuvalu and the Maldives?
- maldives only 2m above sea level and densely populated
- tuvalu 11,000 pop will have to leave by 2100, already many have evacuated to NZ
give three pieces of evidence predicting how GHG emissions will worsen in the future
- before industrial revolution: 280ppm, in 2007: 440ppm
- proves ‘buisiness as usual’
- will reach 550ppm by 2035
- most emissions will come from developing countries, 75% contribution from China and India
why is is difficult to predict future global warming?
- don’t know economic development
- don’t know how much international action will be taken
- don’t know impact of positive feedback mechanisms
what is the predicted impact of a new tipping point being reached on the world?
- irreversible, abrupt changes that can’t be prepared for at regional scale
- mass migration from Africa to Europe
- large scale conflict over food and water
give 3 examples of irreversible changes caused by a tipping point in climate change
- rising sea level
- stopped atlantic thermohaline circulation
- water shortages and agriculture yields
give predicted statistics about impact of sea level rise
- greenpeace, melting arctic ice caps = 10-25cm rise during 20th century
- 21st century, coral bleaching and 1/3 of florida flooded
what is the probability of the atlantic thermohaline circulation shutting down in the future after a new tipping point is reached?
50% chance it will stop in next 200yrs = 50% chance western Europe will be plunged into new ice age
how many globally will suffer from water shortages after a new tipping point is reached?
2.8 billion :(
what is some of the background information on the stern review?
- 2006, first time economist joined environmental debate
- argued probs of global warming could be stopped if GW stopped by 2025
- would cost 1% of world GDP to do this
What were some of the environmental impacts of global warming listed in the stern review?
- 40% world species extinct
- global flooding
- climate belt shift in africa = bad crop yields
- rising sea level = 200 million homeless
what were the two main economic impacts of global warming highlighted in the stern review?
- extreme weather = global GDP lowered by 1% (cost of damage)
- 2-3deg increase = reduce economic output by 3% (crop yields bad)
what were the 4 main options for change suggested by stern in the stern review?
- reduce consumer demand for heavily polluting goods
- global energy supply more efficient
- lower deforestation, balance carbon emissions/keep carbon sinks
- cleaner energy tech
what 3 responses did the UK Government make to reduce the impacts suggested by the stern review?
- target: reduce CO2 emissions by 30% by 2020
- get laws to carbon reduction targets and monitoring of the targets
- create 100,000 new jobs in green tech
