Hazard: Climate Change
Local area: London
Effects of Climate change on London:
1) Sea level rise due to melting polar ice caps, expected to rise by 86cm by 2080!
2) Cold related deaths are expected to fall by 200,000 per year!
3) Heat related deaths are expected to rise by 2800 per year, due to warmer climate, especially affecting the young and old.
4) Food poisoning is expected to rise by 100,000 cases per year, as food is more likely to go off quicker than we are used to.
5) Disasters are expected to rise, for example coastal flooding and storms.
Tornado: a rapidly moving vortex of air, which extends from the comulonimbus (thunder) cloud and to the ground. They are more localised than hurricanes, cause more intense damage in a smaller range and are short lived.
Formations: formed where tropical and polar air masses meet (which happens regularly) but also needs heating from the land and moisture in the air. And a large temperature gradient, hence why tornadoes are more likely occur in summer/spring afternoons.
The ACTUAL formation is uncertain, but what is certain is that we know there has to be cold air above warm air, in order to form horizontal spins, it is then drawn up towards the thundercloud.
7th December, 2006
A tornado hit North London, Kensal Rise, only affected a few streets because it was LOCALISED. But within minutes, roofs were ripped off houses, and cars damaged due to falling debris. FORTUNATELY there were no deaths because it happened at lunch time, only a few injuries.
Floods in London
Floods are London's second most biggest hazard, especially around The Thames.
Four main causes:
1) Heavy prolonged rainfall, lead to surface run off as tarmac and concrete is impermeable, so ran into drains and then added to the rivers.
2) Increased evaporation due to London's hot summers, leads to a backlog in the drains.
3) Storm Surges - occur when tides are highest bringing incoming tides up the Thames to the point where they meet out-going river flow.
4) Low air pressure - exceptionally low air pressure means there is less "weight" on the sea, so it causes it to rise above it's usual level.
The risk of floods has been reduced by The Thames Flood Barrier, it's purpose is to prevent incoming tides from flooding the city.
The barrier was completed in 1982, but it is now TOO SMALL and needs replacing as sea level continue to rise due to global warming. But building a new one would be £30 billion or more, however the consequences of flooding a major global financial center (earning 40% of UK's GDP) would be unthinkable!
Potential Impacts of Flooding on London
1) Lots of the East End would be under water, or just above.
2) Impacts on housing and industry located near and on the Thames, a very economically important area of Canary Wharf.
3) Large population density means evacuation may be difficult and the potential of deaths from drowning.
4) Take a long time to drain the area because it will be mainly under sea level
5) The most vulnerable in poorer areas will also be affected, but be seen to last due to importance.
6) Major trouble caused if the underground is flooded for the whole of the UK.