natural hazards Flashcards
definition of a natural hazard
are extreme natural events that cause loss of life, extreme damage to property and disrupt human activities
types of natural hazard
meteorological-weather, atmosphere or climate eg. hurricanes and bush fires
geological-are caused by the Earth and the movement of tectonic plates eg. volcanoes and earthquakes
factors affecting hazard risk
population-As the world population increases, more people live in areas which are vulnerable to natural hazards
Urbanisation and population density
frequency and magnitude
level of development
prediction
human activities
global distribution of earthquakes and volcanoes
around the Pacific ring of fire
occur at all types of plate boundaries
along the mid-atlantic ridge-underwater mountain range in the Atlantic Ocean
in the Himalayan region-eurasian plate and Indian plate
global distribution of tropical storms
they primarily form at the tropics specifically between 5 degrees and 30 degrees north and south of the equator where sea temperatures are warmer
seasonality of tropical storms
they occur in late summer when sea temperatures are highest over 26/27 degrees and tropical storms require high sea temperatures to form
what is the link between surface winds and air pressure?
Sinking air causes high pressure which leads to winds moving away
Hadley Cell:rainforests
it is between the equator and 30 degrees northern latitude
air rises which causes an area of low pressure
cools and condenses to form clouds
climate=hot-heat form the sun and wet due to the rain
rainforests are very common here
Hadley Cell:deserts
heated air has risen at the equator it divides
half=north half=south
30 degrees northern latitude-it becomes cool and starts to sink
sinking air creates high pressure
clouds cannot form-worlds deserts
characteristics of tropical storms
high wind speeds
intense rainfall
low pressure
the corolis effect causes the winds to spiral around the area of low pressure
formation of tropical storms
1.warm ocean water causes the air to rise rapidly
2.the rising warm air draws in more moist warm air from the oceans surface leading to stronger winds
3. Condensation and Cloud Formation:
As the rising air cools, water vapor condenses and forms large, towering cumulonimbus clouds.
why is there a lot of rainfall at the equator?
the air rises rapidly as it is heated by the sun along the equator. then it cools and condenses to form clouds
primary effects of the Haiti earthquake
-an estimated three million people were affected by the quake
-217,000-230,000 people died
-300,000 people were injured
- 1 million made homeless
-30,000 commercial building collapsed
secondary effects of the Haiti earthquake:
-two million people were left with food and water
-regular power cuts occurred
-crime increased-sexual violence and looting escalated
-by November 2010, there were outbreaks of cholera
Immediate responses to the Haiti earthquake:
due to the port being damaged aid was slow to arrive
-The USA sent rescue teams and 10,000 troops
-235,000 people moved away from Port-au-Prince
-£20 million pounds were donated by the UK government
economic impacts of extreme weather in the uk
extreme weather can lead to agriculture disruption for example leading to crop failures and reducing yield supply impacting food supply chains
