S4 - Coastal Hazards and their Management (C1) Flashcards
What can coastal communities be vulnerable to ?
Extreme natural events such as storms, tsunamis and landslides as well as longer-term risk of coastal erosion and sea level rise.
What is meant by vulnerability ?
The potential to be harmed by a natural hazard. Some coastal communities more so than others.
What kind of physical factors affect vulnerability ?
The magnitude (strength) of the event, its duration, the predictability - unpredictable means less time to prepare and the regularity.
What kind of social and economic factors affect vulnerability ?
Their wealth, levels of education, peoples age (older/younger more vulnerable), overall health, the population density (more victims) and the availability/quality of emergency services.
How can weather events/climate change create vulnerability to coastal flooding ?
Low elevation coastal zones (LECZs) will increase in vulnerability due to rise in sea levels of about 50-100cm by 2100, warmer seas - increase frequency and strength of storms, and increased coastal erosion and storm surges and more violent storms will give more rainfall - increase risk of flash floods.
What is a LECZ ?
Low elevation coastal zone - coastal areas less than 10m above sea level.
What is a storm surge ?
A rapid rise in sea level caused by storms forcing water into a narrowing sea area such as an estuary.
What is isostatic change ?
Change in the height of land relative to the sea, often because of the melting of ice from the last ice age.
What risks are there to the Thames gateway ?
Storm surges, isostatic change - area is sinking into the sea by 2mm a year, changing sea levels - sea level rising 3mm a year.
Why is the Thames gateway particularly vulnerable ?
1.6 mil live and work there, 500,000 properties at risk, 75% property value is here, London City Airport at risk, London is UK’s largest centre of economic activity - contributing 250 billion to UK economy each year.
Why are storm surges a particular threat to the Thames gateway ?
Depressions over north sea create lower pressure causing rise in sea level, wind drift from northerly winds, north sea shaped like a cone and as water pushed forwards into English channel water can’t go anywhere but up - further enhanced by Thames estuary, and following 1953 flood government built Thames Barrier.
What is a delta ?
Landform created by deposition of sediment carried by a river as the flow leaves its mouth and enters slower-moving or still water like an ocean, sea or lake.
What is salination ?
Process increasing salt content of water or soil.
What are environmental refugees ?
People forced to leave their traditional environment because of a marked environmental disruption such as flooding.
What is the difference between primary and secondary impacts ?
Primary impacts are immediate consequences of an event, whereas secondary impacts are ones that result from the primary impact.