Ch 7.4 How does climate change affect us?

Question 1

What are the consequences of climate change?

Answer 1

1. Changes of climatic zones.
2. Strengthen precipitation patterns.
3. Rising sea levels.
4. Extreme weather events.
5. Changes in natural ecosystem.
6. Changes in agriculture and food supply.
7. Relocation of people.
8. Decrease in freshwater supply.
9. Increase in human’s health.
10. Changes in tourist industry.
11. Infrastructure and navigation.

Question 2

Elaborate on changes in climatic zones as one of the consequences of climate change.

Answer 2

Tropical areas will extend polewards (i.e. at an average rate of about 27.4 km per decade in both hemispheres).
Temperate areas will shift polewards.

Question 3

Elaborate on changes in precipitation patterns as one of the consequences of climate change.

Answer 3

1. Climate change can strengthen the existing precipitation patterns(1), which means that wet regions become wetter(2) and dry regions become drier.(3)
2. A rise in air temperature -> Higher evaporation rate.
3. A warm air can hold more moisture(1) -> moisture in the atmosphere increase(2) -> more precipitation in some places: Equatorial, sub polar and polar regions.(3)
4. Drying out the land quickly -> air remains dry -> Fewer clouds and less precipitation in other places: Tropical & Sub Tropical regions over the oceans, the northern part and the southern tip of Africa, western part of Australia and Southern part of North America & South America.
5. Scientists have found that the Sahara Desert has expanded by more than 10% since 1920 because of climate change.

Question 4

Elaborate on rise in sea levels as one of the consequences of climate change.

Answer 4

1. Snow and ice cover melt -> meltwater runs into the ocean.
2. Seawater heats up and expands (Thermal expansion of seawater).

Question 5

Elaborate on extreme weather events as one of the consequences of climate change.

Answer 5

1. More frequent and stronger tropical cyclones, storms and rainfall.
   - Rise in ocean temperatures. -> More energy for storm formation.
   - More evaporations -> More water vapour condenses into water droplets -> release more energy (latent heat).
2. More severe and long-lasting periods of droughts.
   - More evaporation -> drying out the land quickly -> Air remains dry -> Fewer clouds and less rainfall.
3. More heat waves.
   - Warmer atmosphere -> Higher air temperatures.
4. More wildfire
   - More severe and long-lasting droughts & heat waves.
5. More flooding in low-lying areas.
   - Rising sea levels & More frequent and stronger storms and tropical cyclones and rainfall -> Greater surges.

Question 6

Elaborate on natural ecosystem as one of the consequences of climate change.

Answer 6

1. Changes in climate alter the natural distribution limits for vegetation(1) and some species may not be able to cope with rapid climate change(2) -> Migration of species(3) -> Disrupt the balance of ecosystems.(4)
2. Rise in sea levels inundates coastal habitats, such as mangrove forests and marshes(1) -> destroy natural habitats(2) -> extinction of some species(3) -> break down the food chain(4) -> disrupts the balance of ecosystem.(5)
3. Rise in seawater temperatures(1) -> coastal bleaching(2) -> mass die-offs of coral(3) -> disrupt the balance of ecosystems.(4)
4. Ocean acidification as it absorbs more carbon dioxide from the atmosphere(1) -> makes building and maintaining shells more difficult for marine creatures(2) e.g. oysters and clams.

Question 7

Elaborate on relocation of people as one of the consequences of climate change.

Answer 7

Rising sea levels ->
1. Inundate coastal lowlands.
2. More storm surges.
3. Coastal erosion.
4. Frequent flooding in low-lying coastal areas.

Question 8

Elaborate on agriculture and the food supply as one of the consequences of climate change.

Answer 8

1. Warmer and drier climate:
   - 1. Evaporation rate increase -> 2. loss of soil increase -> 3. More erosion -> 4. Land productivity decreases -> 5. intensify desertification -> 6. Shrink the size of farmland -> 7. Food production drops.
2. Warmer and shorter winters -> pests become more active.
   -> 1. More crops will be destroyed -> 2. Food production drops.
   -> 1. Crops are more vulnerable to infection and pest infestation -> 2. Increase the use of harmful and expensive herbicides and pesticides.
3. Increase in drought periods and flooding:
   -> More crops will be destroyed -> Food production drops -> Food supply drops.
4. Rising sea levels:
   -> Inundates coastal farmland -> Shrink the size of farmland -> Food production drops.

Question 9

Elaborate on agriculture and the food supply as one of the consequences of climate change in general.

Answer 9

Farm production is expected to decrease in low-latitude regions(1) but increase in middle- and high-latitude regions.(2) Since warmer climates extend growing season(3) and frost free period.(4) More varieties of crops can be grown in the region(5) and increase farm production. (6)

Question 10

Elaborate on freshwater supply as one of the consequences of climate change.

Answer 10

1. Warmer climate:
   a. - Melting of glaciers and ice caps(1) -> shrinking of glaciers and ice caps (2)-> Freshwater supply increases.(3)
   b. -> Increases in evaporation rates(1) -> Decrease in surface run off(2) -> Freshwater supply decrease.(3)
2. Changes in precipitation patterns:
   a. Precipitation in some areas (e.g. temperate and subtropical area) drops -> decrease in surface run off -> freshwater supply decreases.
   b. Precipitation in some areas (high latitude, tropical area) increase -> freshwater supply increases.
3. Rising sea levels:
   -> Intrusion of saltwater into freshwater aquifers in coastal areas -> groundwater becomes salty -> freshwater supply decrease.

Question 11

Elaborate on human’s health as one of the consequences of climate change.

Answer 11

1. Warmer climate and increase in precipitation(1) favours the breeding of mosquitoes(2) -> More people will be exposed to tropical diseases such as malaries and dengue fever(3). It is because climate change will alter the distribution of parasites(4), bacteria(5) and carriers of infectious diseases.(6)
2. Warmer climate means there will be more heat waves.(1) This will lead to more cases of heat-related health problems such as heat stroke.(2)
3. Cold-related health problems and deaths in cold areas(1) will reduce because of warmer winters. (2)

Question 12

Elaborate on change in tourist industry as one of the consequences of climate change.

Answer 12

1. Alpine areas that rely on skiing and winter sports for income:
   - Warmer and shorter winter shorten ski season and decrease snow cover on mountains. This may adversely affect the tourist industry in these areas
2. Places with mild summers, such as the mediterranean:
   - When summers become too hot, there will be fewer holidaymakers spending vacation there.
3. Place with coral reefs:
   - Warmer seawater will cause coral bleaching. This decreases coral reefs’ attractiveness.
4. High-latitude regions with severe winters.
   - Climate will become milder in high-latitude regions. This helps attract regions.

Question 13

Elaborate on change in infrastructure and navigation as one of the consequences of climate change.

Answer 13

1. Increase in extreme climate events e.g. floods destroys roads and buildings -> economic losses.
2. Melting of permafrost in the Arctic area reduces the stability of infrastructure -> economic losses.
3. Large ice blocks breaking off from ice shelves or glaciers -> pose a great threat to ships travelling in waters around North Atlantic and Antarctica .
4. Melting of ice in the Arctic
   -> Shorter shipping routes and can open up new shipping lanes.
   -> Provides opportunities to tap oil minerals and fisheries resources in the Arctic.