2.b Low energy - Coastal landforms are inter-related and together make up characteristic landscapes

Question 1

How currents affects the Nile Delta:

Answer 1

Delineated nature of currents along this coast is significant in shaping bars that are either parallel or crescentic

Question 2

How waves affects the Nile Delta:

Answer 2

• Low energy environment so not important
• However in future will increase with rising sea levels so will become more significant as more erosion

Question 2

How wind affects the Nile Delta:

Answer 2

• Fact the wind is mainly north-westerly/dominant in one direction is significant because that influences the pattern of currents

Question 3

How tides affects the Nile Delta:

Answer 3

• Low tidal range - low energy environment and means sediment from the delta is not being removed

Question 4

How lithology affects the Nile Delta:

Answer 4

• Influences grain size
• West of Abu Qir we get larger sediment (carbonate sand which is worn down limestone) vs Quartz sand which is finer and found on the Nile Delta

Question 4

How structure affects the Nile Delta:

Answer 4

• Not really a factor

Question 5

Where does which current dominate:

Answer 5

• Rip currents dominate west of Abu Qur
• Longshore drift dominates east of Abu Qur headland

Question 6

Names of distributaries in the Nile Delta

Answer 6

• Rosetta - Distributary
• Manzala - Distributary

Question 7

Deltas:

Answer 7

• Deltas are large areas of sediment that form at the mouth of many rivers
• Deltaic sediment are those deposited by rivers and tidal currents
• Deltaic sediment form when rivers and currents are depositing sediment faster than waves and tides can remove

Question 8

Prevailing wind:

Answer 8

• North-westerly 60% of time
• All comes from the same direction which allows inter-relationships

Question 9

Longshore currents:

Answer 9

• Swash at an angle (prevailing wind)
• Backwash at 90 degrees as under influence of gravity
• Net result is transport of sediment along the coast
• Longshore currents dominate east of Abu Qur headlanf
• Sediment transfer and redistribution of sediment

Question 10

Rip currents:

Answer 10

• Waves break parallel to the shore
• Due to direction of prevailing wind
• Leads to sediment carried out to sea

Question 11

Crescentic Bars:

Answer 11

• Offshore bar
• West of Abu Qur
• Formation lead by dominant rip currents
• Very little longshore drift = directing in direction of prevailing wind

Question 12

Parallel Bar:

Answer 12

• Offshore Bar
• East of Abu Qur
• Formation lead by dominant longshore currents

Question 13

Inter-related: currents

Answer 13

• Landforms east of Abu Qur are inter-related because current erodes the deltas and transports sediment to form parallel bar and barrier bar with lagoon behind
• West - less inter-related due to less longshore current as prevailing wind travels in direction of coast, forms crescentic bar (offshore bar) = consequence, no inter-relationship

Question 14

Inter-related: seasonal - winter

Answer 14

• Velocity of coastal currents ranges from 9.26 to 13.5 cm/s during the summer and increases to 23.14 cm/s in the winter
• Increase in velocity = higher energy due to stronger waves and winds
• Higher energy means more sediment is being transported offshore = more sediment is deposited onto parallel bars
• therefore does not lead to the formation of any other landforms
• Weak inter-relationship

Question 15

Inter-related: seasonal - summer

Answer 15

• Velocity of coastal currents ranges from 9.26 to 13.5 cm/s during the summer and increases to 23.14 cm/s in the winter
• Low current velocity = less energy allowing sediment to be transported along coast by longshore drift
• Sediment is deposited to form barrier bar = traps water leading to formation of lagoon
• Creation of lagoon alters coastal environment = changes patterns of sediment deposition
• Over time can leads to development of salt marshes, mud flat
• Strong inter-relationship

Question 16

Inter-related: future

Answer 16

• Climate change will have a shift in the dominant factors shaping the coastline
• Wave and wind will play a more significant role than currents
• Rising sea level = deeper coastal waters
• Deeper seas allows waves to retain more energy = intensifying coastal erosion
• Turn low energy coastline where deposition dominates = high energy coastline where erosion becomes primary focus
• Increased erosion weakens the connection between landforms as less sediment is being carried
• Less inter-relationships