Outline what is meant by terrestrial albedo. 

Suggest how climate change may cause spatial changes in biomes.

Suggest how climate change may cause spatial changes in animal migration patterns.

Explain two ways in which higher temperatures could increase the incidence of health hazards on people.

Way 1:

Way 2:

A measurement of the amount of sunlight reflected [1].

Development could include: reference to earth/land/sea surfaces [1] / the amount of energy reflected back as a % of incoming solar radiation (measured from 0-1) [1].

Award [1] for a valid spatial change and [1] for additional causal detail.

For example: deserts and semi deserts expand [1] as climate change reduces rainfall totals and reliability [1].

Other possibilities include:

• Some biomes may shift/move/expand/disappear to different latitudes
• Mediterranean vegetation shrinking – the present areas will become drier
• Tundra in the Northern Russia which is shrinking in lower latitudes – permafrost melts due to rising temperatures.
• Boreal forests/Taiga – trees at the southern boundary are experiencing dieback as temperatures increase
• Increase in wildfires – may shrink the area covered by a particular biome e.g. Mediterranean
• Coral bleaching – coral reef biomes are shrinking as sea temperatures increase/acidification takes place
• Mangrove biome shrinking/disappearing/changing position – temperature increase leads to melting ice which raises sea levels.

Award [1] for a valid spatial change and [1] for additional causal detail.

For example: Climate change is driving some species to migrate to new locations especially if they prefer cold climates [1] by moving to higher latitudes or higher altitudes (e.g. Atlantic Mackerel).

Other possibilities include:

• migratory birds – changing routes or patterns/extent of migration
• savanna animals – changing routes or patterns/extent of migration
• loss of sea ice can change migration routes of caribou in Canada – they avoid swimming long distances
• increase in access to green vegetation – decreases need to migrate for caribou
• migration of mosquitoes to areas that are warming – climate change has changed the environment so that it is now suitable
• fish stocks e.g. mackerel migrating poleward in search of cooler waters.

In each case, award [1] for a valid distinct way linked to higher temperatures and [1] for additional explanation/exemplification.

For example: Increased temperature in some regions increase the incidence of vector-borne diseases [1] carried by mosquitoes like dengue fever and the Zika virus [1].

Other possibilities include:

• Weather temperature extremes – heat waves causing increased mortality amongst vulnerable populations such as the older generation due to heat stroke/cardiovascular disease. Linked with mental disorders/lower birth weight. Heat waves are also linked to a number of skin conditions such as rashes/blisters.
• Changes in agriculture could impact upon food availability – nutritional deficiencies.
• Increased water temperatures caused by higher air temperature mean that waterborne bacteria and harmful algal toxins will be present in the water at different times of the year, or in places where they were not previously threats.
• Higher air temperatures can increase cases of Salmonella and other bacteria-related food poisoning because bacteria grow more rapidly in warm environments. These diseases can cause gastrointestinal distress and, in severe cases, death.
• Decrease air quality – raise the levels of ozone and other pollutants in the air that exacerbate cardiovascular and respiratory disease.
• Higher temperatures lead to increased incidence of cyclones – resulting health hazards/mortality.
• Higher temperatures lead to melting glaciers which give sea level rise which contaminates water supplies in lowland areas – leads to hypertension/miscarriage/skin diseases e.g. Bangladesh.
• Release of pathogens from melting ice – melting of permafrost release long dormant diseases e.g. anthrax in Siberia
• Dehydration from increased temperature – can lead to hypertension, cramps and mental issues.

The responses showed a good understanding of the term albedo, and the majority were able to address the terrestrial element of the phrase.

Both sub-sections of this question presented problems for the candidates. Many did not possess the body of knowledge required, especially in the context of biomes. In addition, a number strayed into temporal changes when examining migration patterns. The guide identifies the body of knowledge required in Unit 2:2 of Geographic perspectives.

In (b)i a minority commented on the expansion of deserts or changes in the location and extent of the tundra and taiga. However, the causal element of the question was not usually addressed to acquire the second mark.

Candidates were more successful in (b)ii with a basic comment on animals migrating to environments that suit their environmental requirements, but explanations were frequently superficial. The better answers usually were on fish migrations and ocean warming.

Answers to this question were more secure and candidates generally scored well. Many candidates referred to the link between higher temperatures and the distribution of mosquitos, the increased incidence of heatwaves and changing food production. Some commented on extreme weather events and rising sea level, with varying success in their linkage to higher temperatures. A substantial number however did not provide comment on the resultant health hazard. For example, candidates would comment on the spread of mosquitos but not outline the link to malaria as a health hazard.