Coastal Flooding Flashcards
What is a low pressure atmospheric system
e.g. Hurricanes reduce the atmospheric pressure of sea surface causing it to rise- called a storm surge.
How does strong offshore winds cause flooding?
can force water to higher levels along the coast, allowing waves further inland.
How does tidal currents and surge cause flooding?
may be funnelled into a coastal bottleneck such as the English Channel, forcing sea levels higher.
What happens when these coincide?
Storm surge and wave energy may be intensified by strong onshore winds.
How can a Tsunami cause flooding?
when water is displaced by landslides, volcanic eruptions or submarine earthquakes.
Increase in height massively as they reach the shoreline
How can coastal flooding be caused or intensified by human activity?
Management of River systems
Management of Coastal Systems
Building on coastal lowlands
Reclamation of coastal lowlands
How does Management o river systems cause/intensify flooding?
Some strategies e.g. Dams trap sediment and reduce the amount being deposited at the rivers mouth.
Caused deltas and salt marshes to shrink, providing less protection from high tides and storm surges.
How does management of a coastal system cause/intensify flooding?
Some strategies alter sediment movement, reducing the amount of protective beach material further along the coast.
e.g. Holderness and Spurn Head.
How does building on coastal lowlands cause/intensify flooding?
especially sand dunes, restricted sediment supply to protective beaches and marshes.
How does reclamation of coastal lowlands cuase/intensify flooding?
e.g. reclaimed marshes on east coast of england, draining this land led it to shrink below sea level.
