2a(i) total 6 marks
· Data C is typical of equatiorial climate
Why?
· High mean annual temp. range of 27.5 deg C
· Small temp. range of 3 deg C
· High total annual rainfall of more than 2000mm evenly distributed throughout the year
Why not A and B?
· Not A because A has moderate mean annual temp. range of 11.5 deg C and moderate total annual rainfall of below 2000 mm, characteristic of temperate climate
· Not B because B has unevenly distributed rainfall, which is higher in middle of the year and lower at the end and beginning of the year, characteristic of tropical monsoon climate
3a(i) total 7 marks
Variation with distance from the coast is as follows:
· In January, the further a place of similar height is from the coast, the colder the temperature is in winter.
· In July, the further a place of similar height is from the coast, the warmer the temperature is in summer.
· Thus, A will have a moderate winter temperature of 3 deg C in January as compared to B which will have a more extreme winter temperature of -8 deg C.
· In July, A will have a moderate summer temp. of 18 deg C in July as compared to B which will have a hotter summer temp. of 21 deg C.
· Annual rainfall also falls as a place is further away from the coast.
· Thus, A has a higher annual rainfall of 1208mm while C has 445 mm.
Variation with height above sea level.
· As altitude (height) increases, temperature decreases while rainfall increases.
· Thus, B’s temperatures in July and January are lower than both A and C as it is located at a height above 2000m while the other 2 are found below 1000m.
· Annual rainfall at B, on the other hand, is higher with 1525mm as compared to A with 1208mm and C with 445mm.
3a(ii) total 5 marks
Seasonal differences in temperature between areas A and C in January and July because:
· Of maritime effect, which is the effect that large ocean bodies have on the climate of coastal areas such as area A.
· During summer in July, the air over the land heats up quickly, while the air over the sea gains heat much slower than the land.
· The cooler air over the sea helps lower the temperature of Area A, found along the coast, contributing to a lower summer temp. of 18 deg C as compared to C’s 21 deg C.
· On the other hand, during winter in January, the air over the sea remains relatively warm compared to the air over the land because the sea takes a longer time to lose heat.
· The warmer air over the sea helps to raise the temperatures of Area A, contributing to a higher winter temp. of 3 deg C as compared to C’s -8 deg C.
3b(i) total 5 marks [must use information from Fig. 7]
Bangladesh is frequently flooded because of both natural and human causes such as:
· Excessive rainfall brought about by the southwest monsoons à excess rainwater is unable to seep into the ground or rivers overflow their banks
· Storm surges due to strong winds of the tropical storms and
· the fact that 80% of Bangladesh consists of a low flat floodplain and delta
· Melting of the snow on Himalayas mountains à fed excessive water into the Brahmaputra and Ganges Rivers that drain Bangladesh
· Deforestation in foothills of mountains north of Bangladesh means that surface runoff will be higher after heavy rainfall
3b(ii) total 8 marks
Marking Scheme (Marks allocation for each level are fixed)
Level 1 (0-3m)
Level 2 (4-6m)
Level 3 (7-8m)
Details on strategies to reduce the effect of river floods
· Building artificial dykes, which are walls of sand, stone and concrete built along river banks prone to flooding
· Eg. In China, dykes have been built for centuries in the lower course of the Yellow River
· Construction of dams where walls of dams have gates which hold back or release water from the man-made reservoir behind it.
Level 1 - Generic responses without details on strategies to reduce the effect of river floods
Level 2 - Some details on strategies to reduce the effect of river floods
Level 3 - Many clear details or egs. on strategies to reduce the effect of river floods
Links between strategies and how they help reduce the effect of river floods
· Dykes help increase the capacity of the river to hold water, thus reducing its chances of flooding.
· Dams control the amount of water that flows downstream in a river, thereby reducing the occurrence of floods downstream.
· Flood insurance
· Building control
· Monitoring and education
Level 1 - Simple statements on the links between strategies and how they help reduce the effect of river floods
Level 2 - Some developed statements on the links between strategies and how they help reduce the effect of river floods
Level 3 - Many well developed statements on the links between strategies and how they help reduce the effect of river floods
Assessment or evaluation of the effectiveness of the different strategies to help reduce the effect of river floods
Shows limitations of the strategies
· Dams can be very costly
· Constant deposition on river bed limits the effectiveness of dykes
Level 1 - No attempts at evaluation
Level 2 - Some attempts at evaluation but weaker in explaining the effectiveness or limitations of the various strategies
Level 3 - Evaluation includes how effective and how limited the various strategies are in reducing the effect of floods
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