hazards Flashcards
define natural hazard
a natural events that threatens people or has the potential to cause damage, destruction ,death
define hazard risk
the probability or chance that a
natural hazard may take place
define the 4 different types of hazards and give an example:
- Tectonic hazards
- Atmospheric hazards
- Geomorphological hazards
- Biological hazards
- caused by movement of tectonic plates (volcano eruptions, earthquakes)
- hurricanes
- occur on the earth’s surface (flooding)
- involve living organisms (forest fires)
where are the different types of tropical storms found:
- hurricane
- cyclone
- typhoon
hurricane- USA, Caribbean, Atlantic ocean
cyclone- South east Asia, Australia, Indian Ocean
typhoon- Japan, Philippines, Pacific ocean
where do tropical storms form?
5-15 degrees north and south of the equator
( at the equator there isn’t enough spin from the rotation of the earth, this causes the Coriolis effect)
sea temperature above 27 degrees Celsius
sea depths from 60-70m
what effect is climate change going to have on tropical storms
changed intensity
- 1 degree Celsius increase in sea temperature = 3-5% increase in wind speed
- more category 4-5 storms
- wind power increased in storms by 3-5%= build houses that withstand that wind speed
changed frequency
- category 4 to 5 are increasing
- category 1 to 3 are decreasing
changed distribution
- are expected to spread due to increasing sea temperature = storms can form where they couldn’t before= sea levels rising more places above 60m sea depth
( increase in temperature= rise in sea levels due to thermal expansion, rising sea levels= more storm surges, warmer atmosphere= air holds more moisture= increase in heavy rainfall= more destructive flooding)
increased uncertainty as the rate of climate change is unpredictable already increased risk to life and homes due to population pressure
how will thermal expansion cause more damage to properties
sea level rises as sea water warms and expands as the particles have more energy
this creates higher more dangerous storm surges with more energy
which destroy coastal properties
What happens where the Ferrel and Polar cells meet
above the tropic of cancer
hot air rises causing mixed unstable weather due to low pressure
the air rises and moves north then cools and sinks at the north pole
this creates high pressure which means dry but cool conditions
what happens between the tropic of cancer and Capricorn
in terms of air moving
at the equator hot air rises forming low pressure
air cools and condenses forming clouds
thunder storms develop with cumulonimbus clouds causing heavy precipitation
cold air travels away from the equator and sinks
where the cold air sinks deserts are formed
what happens below the tropic of Capricorn
In the Ferrel cell, hot air rises over Europe and Northern USA which creates low pressure
So it rains frequently
At the tropics cool air sinks forming high pressure
This creates hot conditions and deserts
what are trade winds
trade winds blow from areas north and south of the equator towards the equator transferring warm air (tropical rainforests). Westerlies blow north from the Tropic of Cancer and south from the Tropic of Capricorn. These conditions combine to cause settled warm climates with cooler nights (Mediterranean)
what are conditions like in the eye of the storm
calm
quiet
dry
what are conditions like in the eye wall
dangerous
windy
heavy precipitation
what is the:
1. width
2. wind speed
of cumulonimbus clouds
- width- 150 km
2. wind speed- 350 km/hr
define thermal expansion
liquid particles get more energy so sea level rises as particles move around more
