Coastal Topic Flashcards
Name The Inputs Of A Coastal System
Land, people, atmosphere, marine, solar energy, waves, wind, tides
Name The Outputs Of A Coastal System
Erosion, Transportation, deposition, weathering, mass movement, salt marsh, wave cut platform, long shore drift, abrasion, freeze thaw
What Is The Top Of A Wave Called
The crest
What Is The Bottom Of A Wave Called
The Trough
What Is A Wave Length
The distance between each crest
What Is The Hight Of A Wave Called
The amplitude
What Is Wave Frequency
The amount of waves that pass a certain point in a time frame
Name The Key Aspects Of Destructive Waves
*Strong backwash
*Weak swash
*Appears on steep beaches because it washes the beach away
*Washes away sediment
*Deposits sediment off shore
Name The Key Aspects Of Constructive Waves
*Strong swash
*Weak backwash
*Build up beaches
*Deposits sediment onto the beach
How Is Sediment Formed
Sediment is formed from eroded cliffs and rocks
Why Can Building Sea-Walls Be Bad
Because by building sea walls we are stopping the coast from being eroded, which reduces the amount of sediment that constructive waves can deposit
Explain The Negative Feedback System Of Waves
Destructive waves wash away the beach until it is too steep for them to continue, they turn into constructive waves which build the beach backup. Once the beach is built up, destructive waves return to erode the sediment. And the cycle continues
What Force Created By The Moon Creates Tides
Centrifugal force
Why Is There A High Tide On The Side Of The Earth Closest To The Moon
Because the gravity of the moon pulls the water towards it
Why Is There A High Tide On The Side Of The Earth Opposite The Moon
Because the moons gravity pulls the earth into the center of the water meaning some “sticks out” on the other side
Why Are There Two High Tides And Low Tides In 24 Hours
Because a singular point on the earth passes through both high tides and low tides in a 24 hour period
Define Spring Tides
Spring tides are tides that occur every 14 days, they occur when the sun is in line with the moon. This causes extra gravitational pull on the oceans causing higher high tides, and lower low tides. They occur on full moons and new moons
Define Neap Tides
When the sun and the moon are at 90 degrees from each other, this makes the tide line a circle, meaning that there isn’t much difference between high tide and low tide. They occur every 14 days on a quarter moon
What Is Tidal Range
The difference between high and low tide
What Is The Cool Temperate Western Maritime Climate
The CTWMC is between 45-65 degrees of the equator and causes high energy waves where the north and south winds meet.
Why Do Winds Blow To The West
The Coriolis force means that the earth spins to the right. If you went straight south in the atmosphere you would end up west of where you wanted to be. Because of this effect, the winds are pushed westwards with the spin of the earth.
What Current Causes Wind
Convection current. As the hot air rises higher into the atmosphere, cold air rushes along the surface of the earth to fill the gap the rising air created. As the hot air moves along towards the cooler temperature and gets colder, it sinks.
What Is A High Pressure System
A high pressure system the when the cold air sinks towards the surface of the earth
What Is A Low Pressure System
When the hot air rises higher into the atmosphere
What Are High Energy Coasts
High energy coasts are area with high energy waves caused by the CTWMC
Where Are Storm Wave Environments Found
Between 45-65 degrees because of CTWMC
What Causes The East Coast Swell
The east coast swells are found on the east coast of each continent bellow the tropic of Cancer caused by NE and SE trade winds
Where Are Tropical Cyclone Coasts Found
Tropical cyclone coasts are found in the high pressure areas either side of the equator
What Are Trade Winds
The trade winds are winds that reliably blow east to west just north and south of the equator.
What Are Prevailing Winds
Prevailing winds are winds that blow from a single direction over a specific area of the Earth.
Air Pressure System Sheet
Define A Storm Surge
An abnormal rise of water generated by a storm, over and above the predicted astronomical tides
Why Does The UK Have Big Waves
The whole of the UK has big waves because there are wind blowing in from the North-East and the South-West
What Is The ‘Formula’ For A Storm Surge
Spring tide + low pressure storm + bulge in the sea = storm surge
Why Do Low Pressure Systems Cause Bulges In The Ocean
High pressure pushes the ocean to create a concave surface. Low pressure draws air up and in doing so the air pulls the water into a bulge as it moves across the ocean and rises
What Is The Coriolis Force
When all the water is diverted to the right because of the spin of the earth
Name And Explain The Human Causes Of Storm Surges
*Damming the rivers (flood defences) - decreases deposition in the estuary e.g. less salt marshes. This eliminates a natural defence
*Management of coasts - alter the amount of protective beach material that would be deposited acting as a barrier to rising sea levels. (sea walls)
*Building on coastal low lands makes people vulnerable to area that would flood naturally
*Global warming causes warmer weather which causes the sea to expand and sea levels to rise. Length of rainfall has been the most exceptional for 248 years
What Is A Sediment Cell
A sediment cell is a stretch of coastline usually bordered by two prominent headlands or anything that stops sediment movement. Where the movement of sediment tends to be contained.
Inputs Into A Sediment Cell
These are primarily derived from the river, coastal erosion and off shore sources, such as bars and banks
Transfers In Sediment Cells
The involve longshore drift together with onshore or offshore processes such as rip currents
Stores In A Sediment Cell
These include the beach, sand dunes, and offshore deposits (bars and bands)
Define Currents
The permanent or seasonal movement of surface water in the sea and oceans
What Is An Upwelling Current
The movement of cold water from deep in the ocean towards the surface. The more dense cold water replaces the warmer surface water and creates a nutrient rich cold ocean current. These form part of the global ocean circulation currents.
What Is Longshore Current
Also known as littoral drift, occur as most waves do not hit the coastline head on but approach at an angle to the shoreline. This generates a flow of water (current) running parallel to the shoreline. This not only moves water along the surf zone but also moves sediment parallel to the shoreline.
What Is A Rip Current
Rip currents occur when the receding flow becomes concentrated in one particular area at one particular time. There are a number of things that can cause this but the most common is a break in a sand bar.
Define Mass Movement
The movement of consolidated and unconsolidated material due to gravity
Define Consolidated Rock
Solid rock
Define Unconsolidated Rock
Soft rock (clay and soil)
Why Do We Have Boulder Clay Along The Coast
The boulder clay that we build on is so compact because as glaciers moved towards our coast, it pushes the mud and material from the sea bed against the coast