Coasts 6 Markers (1)

Question 1

Analyse the data shown in figure 5 (Oman Sea and Chabahar Bay) (2018)

Answer 1

 This is a coastline which is being affected by longshore drift. The
sediment cell is approximately 50-60 km long and the longshore current is moving sediment from east to west. The dominant wave direction is north, north-west. It suggests that waves must be hitting the coastline at a slight angle moving the sediment in a westerly direction.
 There appears to be no coastal protection in place and significant quantities of material are being moved annually - 70,000 m3 from the eastern end of the littoral cell.
 The sediments appear to be being moving in an anti-clockwise direction around the bay. There is a significant input of sediment (240,000 m3) into the bay presumably as a result of river deposition.
 Overall the bay is experiencing significantly more deposition than erosion due the contribution of longshore transported material and the input from the river.

Question 2

Analyse the data shown in Figure 5 (Distribution of beach erosion and accretion from 1984 to 2016) (2019)

Answer 2

• There is significant variation in the rates of accretion and erosion of sandy beaches across the world.
• Overall, across the continents, beaches are experiencing net gains, most notably in south-east Asia. This area is experiencing accretion rates over 1m/yr greater than any other continent.
• In terms of locational patterns there are some distinct bands where
erosion is dominant (e.g. India or the band stretching from the Mediterranean to east coast of Africa). There are some bands of significant accretion e.g. south east Asia and northern Canada
• Some may argue that in terms of longitudinal analysis, there is some evidence of mirroring i.e. where rates are high for erosion, there is some evidence that rates are also high for accretion and vice versa.
• Some may suggest that this is not the case and point to anomalies
such as 30oW or 144oW. At 30oW for example, there is evidence of
erosion running at over 50% with accretion at only around 5–10%

Question 3

Analyse the relationship between isostatic adjustment and the 2010
melting day anomaly in Greenland as shown in Figure 5. (2020)

Answer 3

• There appears to be some correlation between the 2010 melting day anomaly and uplift.
• The uplift is all coastal according to the data, with neither melting nor uplift taking place inland.
• The south of the island is generally experiencing more uplift than the north.
• In places where melting is higher than the 1979–2009 average, there has been more uplift in 2010. This can be seen on the south-east of Greenland, where the melting day anomaly is recorded to be +40 days and higher, in the same areas most significant rate of isostatic rebound was recorded.In senu for example ,ice is experiencing more than 60 days above average melting, this coincides with around 20 mm of uplift.
• The pattern is by no means consistent though. At kely, this area (to the east) experiences the highest concentration of melt anomaly but only around 5–6 mm of uplift.

Question 4

Analyse the data shown in Figure 5. (The distribution of coastal erosion and accretion (sediment build up) across selected European coastlines in 2004) (2021)

Answer 4

• The overall picture is very mixed across the European coastlines.
• There are large areas experiencing accretion, particularly around
northern Europe.
• The picture around the Jutland peninsula is hard to decipher and
somewhat unclear.The picture is mixed here with what looks like more accretion than erosion.
• The Mediterranean coastlines are almost all either eroding or stable with only small pockets of accretion such as in northern Italy. Spatially, most of the erosion along the Mediterranean coastline takes place on Greek’s coastline in Myrthoan sea and sea of Crete and as well Italy’s coastline in Ionian Sea.
• It is interesting to note that the islands of Madeira and the Canaries are both exposed coastlines but experiencing stability.

Question 5

Complete Figure 5 and interpret your Chi-square result using Figure 6. 9 (Specimen)

Answer 5

196
2.67
11.68

The 𝑥2 figure of 11.68 exceeds both the 0.05 and 0.01 significance levels (1). This means that the null hypothesis can be rejected and that there is a significant difference in the location of the worst floods to affect Great Britain (1). There is a less than 1% probability that these results could occur by chance (1). Looking at the data, it is clear that flooding is much more likely (with statistical significance) to affect the south west compared to other locations, most notably the north east (1).