Natural Hazards (paper 1) Flashcards
what are the four categories of hazards
- atmospheric
- geomorphological
- tectonic
- biological
what are atmospheric hazards
weather and climate related (hurricane, drought)
what are geomorphological hazards
land surface hazards (sinkhole, landslide)
what are tectonic hazards
linked to movements in the earth’s curst (earthquake, volcano)
what are biological hazards
relating to plants and animals (forest fires)
define natural hazard
a natural event that causes loss of life and/or damage to property
what is the difference between a natural event or hazard
an event just happens and there is no loss of life, a hazard kills and damages
what two categories of hazards are geological
tectonic and geomorphological
what two categories of hazards are meterological
atmospheric and biological
define geological hazard
caused by land and tectonic processes
define meteorological hazards
caused by weather and climate
what name is given to a colour key map of the world
choropleth map
are earthquake loactions associated with plate boundaries
yes highly
are volcano locations associated with plate boundaries
yes extremely
are tropical storms associated with plate boundaries
no - they only occur close to the equators
what factors affect hazard risk
- more densely populated areas and countries
- buliding on hazardous lands (flood plains / volcano surroundings)
- relief of the land
- climate change (warmer = more intense storms)
- poverty (forces people to live in hazardous areas)
- topography of land
- magnitude and frequency of an event
- location (on tectonic plate)
define hazard risk
the chance or probability of being affected by a natural hazard
what are the two different types of effects
- primary
- secondary
what are primary effects
an impact or effect of a hazard that occurs as a direct consequence of that hazard (roof tiles falling off / death)
what are secondary effects
hazards that result from an initial event but happen at a later date (diseases / mudslides / ash clouds)
why do people live in hazardous areas
- geothermal energy sources (volanic areas) - iceland & italy
- desired climate
- soil fertility (volcanic areas) - tomatoes in iceland
- resources underground (diamonds) - america
-tourism - blue lagoon Iceland - earthquakes are coastal - helps for fishing
what is the radius (distance from the centre) of earth
6300 km
how many large tectonic plates are there
7
describe the mantle of the earth
- widest & thickest layer
- high viscosity on outside
- low viscosity closer to middle