Coasts - Theme 2 - TIDES Flashcards
1
Q
What causes the tides
A
-Gravitational pull of the moon and sun
2
Q
What is tidal range
A
-range between high and low water mark
3
Q
When is there a high tide
A
- when the earth points towards the moon then a high tide occurs as gravity pulls the ocean towards the moon
- likewise the opposite of the world has a high tide
- 90 degrees will have a low tide
4
Q
When is there a low tide
A
-When the ocean is 90 degrees from the moon
5
Q
What is a spring tide
A
- When the moon and sun both have an effect on the ocean
- When the moon and the sun are in allignment there is a spring tide
- two a year
6
Q
what is a neap tide
A
- When the moon and sun both have an effect on the ocean
- when the moon and sun are at 90 degrees
- two a year
7
Q
What does a low tidal range not cause for the coast
A
- less wave energy
- less erosion
8
Q
What does a high tidal range cause
A
- high wave energy
- more erosion
9
Q
What is a macro tidal
A
-large tidal range - bigger then 4m
10
Q
What is a meso tidal range
A
-between 2-4m
11
Q
What is a micro tidal
A
-less then 2m
12
Q
What is a strom surge
A
- an area of low pressure on the surface of sea means sea level rises due to less pressure
- 1cm for 1 millibar(mb) drop
13
Q
How does a strom surge form
A
- Strong winds
- low pressure system allows low pressure over the sea (depression)
- sea level rises underneath - 1cm for 1mb drop
- piles up against the coast
14
Q
What areas of the UK are effected by storm surges
A
- North sea
- East coast
- funnels the water