Zusammenfassung der Ressource
How is coastal
development
increasingly at risk
from and vulnerable
to physical processes?
- Changes in
sea level
- Currently rising as
ice-sheets and
glaciers are melting
due to GW
- GW also
causing thermal
expansion of
seawater - rising
- Risen about
15cm in the last
100 years and
30cm by 2100
- Sea levels also
vary due to
changes in tectonic
movement
- Will lead to severe
flooding in small
islands and flood
plains such as
Bangladesh
- Storm Surges
- Caused by
atmospheric
depressions
- At sea they
generate
larger waves
- A drop in
atmospheric
pressure can cause
sea levels to rise
and therefore
flooding
- London is at risk to
storm surges because
of the Thames and the
buildings of historical
and cultural value
- Tsunami's
- A series of very large
waves generated by a
disturbance on the
ocean floor
- Such as an
earthquake,
volcanic activity
or a landslide
- First signs
include a small
rise in the water
level followed by
deeply receding
water level
- Poses great
threat to coastal
settlements,
especially in
LEDC's with little
warning
- Coastal Erosion
- Holderness
Coastline
- The Holderness
coast is in the
north east of
England.
- Strong prevailing
winds creating
longshore drift that
moves material
south along the
coastline.
- The cliffs are made
of a soft boulder
clay. It will
therefore erode
quickly, especially
when saturated.
- This is one of the
most vulnerable
coastlines in the
world and it retreats
at a rate of one to
two metres every
year.
- Mappleton and the cliffs are
no longer at great risk from
erosion. The rock groynes
have stopped beach material
being moved south from
Mappleton along the coast.
- Types of erosion
- Hydraulic
action
- Abrasion
- Attrition
- Solution
- Wave Attack
- Freeze-thaw
- Biological
action
- Corrosion
- Factors
affecting rate of
erosion
- Shape of
coastline
- Width of
beach
- Length and
direction of
fetch
- Where
the wave
breaks
- The height
or steepness
of wave
- Wave
energy
- Rock
resistance
- Structure
- Human
activity
- The coastal
sediment
system