Lecture iv - Effects of Climate Change Flashcards
1
Q
Greenhouse Gases … since 1900s. Why?
A
Increased
- due to increased human activities esp. during the Industrial Revolution that sees much rapid development in many countries
2
Q
Classify effects of climate change
A
- Range of impacts
-primary vs secondary
- environ/climatic
- social (qlty of life)
- econ
- political (govnance) - Spacial scale of impact
- global
- regional
- national
- local/community
- DCs vs LDCs (variat n) - temporal scale of impact
- short vs long term
3
Q
Summarise effects of contemporary climate change
A
- more ENSO & its impacts (intensif n of natural disaster eg hurricane, drought)
- melting polar ice caps, glaciers, rising sea lvl
- impact on ecosystem
- spread infectious disease eg malaria, dengue
- opening of northern Sea route
- impact on food product n
- increased natural disasters & associated impacts (social, econ, environ)
4
Q
Explain climatic changes as effect of climate change
A
- global warm can hv sig impact on climate
=> greater extremities in temp & rainfall
=> hydrological impacts eg flood, drought (extreme climatic events) - global warm cld lead to increase in MORE extreme ENSO events (& cause ocean-atmos circulat n change & impacts)
5
Q
Describe how climate change affects ENSO
A
- In 1982-83, brought most serious condit n ever seen, caused $8 billion damage (econ impact) & 1000 ppl dead (social impact)
- areas w usual high precipitat n will now experience droughts eg SEA, India
- heavy intense rainfall might cause floodings eg Peru, S. America
- INCREASED FREQUENCY
El Nino usually occur every 7 yrs but recently, due to enhanced ghg effect, time period for this phenomena is shortened to 3-4 yrs - INCREASED MAGNITUDE (scale of event)
impacts of El Nino r now more severe as extreme climatic conditions become more destructive
6
Q
Explain how climate change affects marine ecosystems
A
- more frequent increase in sea surface temp (SST) can hv detrimental effects on marine ecosystem
Eg bleaching of coral reefs - Coral bleaching threatens all organisms that depend on reef:
• (Social impact) Species use corals as habitat and food (fish, mammoth whale shark, endangered salt water crocodile) => disrupt food chain, food supply
• (econ impact) Local communities depend on reef for food, income, & tourist biz => takeaway livelihood of local fishermen - weaker reef, mean less shoreline protection from storms and erosion
- Other impacts of coral bleaching r; loss of coral islands, decline in species diversity & changes in the overall reef communities
7
Q
Explain how global warming affects hurricanes
A
- more ghg gas trapped in atmos, higher SST
=> more occurence (frequent) of cat 4, cat 5 (mag) hurricanes due to stronger thermal reservoir - more intense vortex can b generated
Evidence: - cat 5 hurricane Mitch along coast of Honduras (America) is strongest storm in 1998 (cause torrential rainfall, widespread flood, landslide)
- > = 11 000 killed, 9000 missing + econ damage USD$2 billion
8
Q
Explain how global warming affects heat waves
A
- heat wave occur when high Pa systems strengthen, remain over region
- high Pa system fr air sinking cause little, no convect n, inhibit form n of rain, prevent heat fr rising
=> trap heat, cause heat waves - more ghg gas oso trap radiating heat => increased temp
9
Q
Explain impact of climate change on polar ice caps, glaciers and sea levels
A
- increased temp can lead to melt of ice caps, glaciers
=> sea lvl rise - rising by 1.7mm/yr over last century, abt 10-15cm over past century
–> due to global warm, it cld rise by as much as 1m by 2100
=> detrimental effects: - inundate deltas (physical impact), reducing amt arable land for agri & livelihood (socio-econ impact)
- Tourism: some biz can b affected eg skiing industry can go out of biz bcos increase in snow melt (econ impact)
10
Q
Explain impact of climate change on aquatic and terrestrial ecosystems
A
- change in distribut n of flora & fauna - general shift to diff latitude
=> species that can oni grow/thrive within specific temp range must migrate to diff latitude or die-off due to global warm
eg many fish species move northwards, search for cooler waters. Cod fishes move polewards in Atlantic Ocean - research show as earth heats up, climate zone shift outwards fr equator
=> countries north of equator eg UK find themselves living in recognisable climate of countries far closer to equator, as will southern countries eg New Zealand - within our lifetime, London may hv climate of Southern France, while scorching deserts of northern Africa may creep into Europe
11
Q
Explain how climate change affects spread of infectious diseases
A
- CC promote ideal condit n for breeding
- climate related events eg flooding/rain create spawning pools for mosquitos to breed/spawn
- diseases/disease carriers thrive in hotter, wetter temp
=> spread of diseases into non-tropical areas eg malaria, zika, dengue
=> 60 % of world projected to be in malaria zone by 2100
12
Q
Explain how climate change creates Northern Sea route
A
- melt Arctic Ice open Northwest Passage in summber
- until 2008, Arctic-pack ice prevented regular marine shipping thruout most of year
- change in pack ice (Arctic shrinkage) rendered waterways more navigable
- offer alternatives for shipping routes btw europe & asia
- as ice melts, range of activities increase
eg shipping, oil & gas explorat n, tourism (all cld bcome more accessible as ice recedes) - warming can oso create new border disputes as countries increase their military presence in Arctic
- if part of Arctic bcome ice-free, new sea routes can open up which may disrupt economies of some cities/countries eg Singapore
13
Q
Explain how climate change affects food production
A
- increase in temp can affect precipitat n & soil moisture across regions in world, leads to major shifts in agri
- particularly devastating on countries engaging in primary product n as impt econ sector
–> crops tend grow faster in warmer condit n (but oso depend on yield condit n)
POSITIVE IMPACTS:
- gradual greening or northern latitude fr 1980 onwards
- grow season increased by 11 days on avg since early 1960s
NEGATIVE IMPACTS:
- high probability grow season temp in tropics & sub-tropics bcome more extreme, too hot to grow certain type crops
14
Q
Explain how climate change affects natural disaster frequency
A
- Increase in natural disaster
- Floods: brought abt by hurricanes or increased rainfall
eg Mississipi flood, 2008 - Droughts: increased temp due to ENSO or other factors
=> environmental refugees
15
Q
Briefly explain how climate change affects different types of location. What can be done?
A
- low-lying coastal areas more prone to flood due to rise sea lvl
–> can b further caused, even aggravated by human activity or natural disaster - issues stemming fr geographical locat n cnt b altered but can b mitigated thru HARD and/or SOFT engineering methods
