Environmental hazards
What is a 'natural hazard'?
A natural hazard is the threat of a naturally occurring event happening in a particular area often without warning, which has negative impacts on people and the landscape. Examples of natural hazards include An intense storm that forms in places with warm seas. Sometimes called hurricanes or typhoons., The sudden movement of the earth's crust., A landform created by an area in the Earth's crust through which lava, steam and ash may erupt. and A large destructive wave caused by earthquakes, volcanic activity or landslides under water..
Globally, natural disasters kill 60,000 people per year, on average.
Tropical storms
Location
Tropical storms are found between the The line around the centre of the Earth, parallel to the Tropics of Cancer and Capricorn. and the An important line of latitude located at 23.5° north of the Equator. in the northern hemisphere and between the equator and the An important line of latitude located at 23.5° south of the Equator. in the southern hemisphere.
They originate over the eastern side of oceans and move westwards where, when they cross land, they cause great devastation before dying out. Tropical storms over 74mph are called The name for a tropical storm in the USA. in the USA, The name for a tropical storm in India . in India and The name for a tropical storm in China. in China and Japan.
The main features of tropical storms
Causes of tropical storms
In order for a tropical storm to form, the following conditions need to be met:
- sea temperatures must be over 27°C
- low The weight of the air in the atmosphere.
- air spiralling upwards
- large expanse of water
- location between the tropics
- damp, moist air with The amount of water vapour in the atmosphere measured as a percentage. greater than 60% per cent