1.b. Coastal landscape systems are influenced by a range of physical factors.

Question 1

Potential influences on coastal landscape systems of:
- winds, including speed, direction and frequency

Answer 1

Wind speed, direction + frequency DETERMINES WAVE ENERGY

Speed-

Faster + stronger winds -> more energy -> higher energy waves -> destructive waves -> higher rates of erosion

Waves with less energy -> deposit more -> building the beach

Direction-

Direction of prevailing wind -> determines direction of LSD -> landforms such as spits and bars can form

Frequency-

more winds -> more aeolian processes -> coastline will be shaped by winds

Fetch= distance wind has travelled over uninterrupted water
Long fetch = more wave energy

Question 2

Potential influences on coastal landscape systems of:
- waves, including wave formation, development and breaking

Answer 2

Wind speed, direction + frequency DETERMINES WAVE ENERGY

Constructive
- Low energy
- Stronger swash than backwash -> adding sediment to the beach -> net gain
- Lower frequency (6-8 per min)
- Lower and longer waves

versus

Destructive
- High energy
- Stronger backwash than swash -> takes sediment away from beach -> net loss
- Higher frequency (11-14 per min)
- Taller and shorter waves

Different types of breaking waves-
- spilling
- surging
- plunging
-> effects beach profile

Question 3

Potential influences on coastal landscape systems of:
- tides, including tidal cycles and range

Answer 3

Short term changes in sea level determined by the gravitation pull of the moon -> high tide follows the moon

When the sun + moon are aligned -> strong gravitational pull
-> spring tides with high tidal ranges

When the sun + moon are at right angles to each other -> week gravitational pull
-> neap tides with low ridal ranges

Neap and spring tides -> differing tidal range -> effects rates of erosion of landforms

Evaluation- these are short term changes -> therefore having limited long term effects on the coastline

Question 4

Potential influences on coastal landscape systems of:
- geology, including lithology and structure

Answer 4

Lithology = the composition of rocks -> including chemical and physical composition

Structure= the properties of rocks -> including joins, cracks + pores

• how reactive minerals in the rock are -> effects rate of chemical weathering
• whether the rocks are clastic or
  crystalline:
  clastic - sediment particles cemented together
  these are sedimentary rocks e.g. sandstone and clay

crystalline- interlocking mineral crystals
these are indigenous e.g. granite and metamorphic rocks e.g. marble

• the amount of joints, cracks + pores -> these weaknesses are exploited by erosion and weathering

sedimentary rocks also may have bedding planes- more vulnerable to erosion

the angle the bedding planes are pointing -> influences cliff profile -> landward + horizontal = steep vs seaward = gentle

how rocks lie on a coastline-

discordant =
alternating bands of hard and soft rock lie PERPENDICULAR to the coastline -> formation of headland + bays

concordant =
alternating bands of hard and soft rock lie PARALLEL to the coastline -> straighter coastline -> coves can form

Question 5

Potential influences on coastal landscape systems of:
- global pattern of ocean currents.

Answer 5

The global masses of water -> that transfer heat around the planet

Warm ocean currents = low latitudes -> polar regions

Cold ocean currents = polar regions -> low latitudes

Evaluation- has little effect on coastal processes -> however directly impacts air temperature -> therefore sub-aerial processes of weathering + mass movement

rip currents-
help transport sediment
either caused by tidal motion or waves breaking at right angles to the shore
a cellular circular is created when the wave returns to the sea -> this is created by differing wave heights

wave with a larger height breaks on the beach and when it returns back to the sea, dragging back the wave with the lower height
this movement of water can produce cups on the shoreline