Physical - Hazardous Environments Flashcards
(28 cards)
Hazard
def
an event that threatens or actually causes damage and destruction to people, their property and settlements
Why are some places more vulnerable to Hazards [4]
- Some places experience more than one type of natural hazards events
- Some places experience natural disasters more frequently than others
- In some places, hazards are stronger and more destructive than others
- Some places are able to cope to the impact of disasters better
Geological Hazards [3]
Earthquakes
Volcanic eruption
Landslides
Climatic Hazards
Storms
Flood
Drought
Biological Hazards
Fires
Pests
Diseases
Technological Hazards
Nuclear Explosion
Transport accident
Pollution
Formation of a tropical cyclone [5]
- High temperatures of air rise from the surface of the sea
- The rising causes local thunderstorms
- Small storms come together to create a strong flow of rapidly rising air
- Produces an are of increasingly low pressure
- Shear winds cause it to rotate, setting the tropical cyclone into motion
Features of the eye of a tropical cyclone
Calm, low pressure
Conditions for a tropical Cyclone to develop [5]
- Deep layer of warm(>27), humid and unstable air
- Supply of heat an moisture from the surface of the sea
- The sea must be at its warmest (summer)
- Circular motion of the air encouraged by the Coriolis Force
- Small changes in wind speed and direction with changes in altitude (shear)
Distribution of tropical cyclones
Formed close to the equator, mostly reach unto within the tropics
Characteristics of a tropical Cyclone [3]
- Strong winds
- Triggers landslides and mudslides
- Storm Surges
Types of plate margins [4]
Collision: Land moving towards land, creates mountains
Destructive convergent: Oceanic and continental move together, oceanic submerges below
Constructive: Two plates move apart, volcanic eruptions, new land created
Conservative: Sliding across in different directions or speeds
What causes tectonic plates to move
Convection currents in the magma
Volcanic eruption characteristics [5]
- Lava Flow
- Ash cloud
- Rockfall
- Gas emmision
- Pyroclastic flow
Earthquake epicenter vs focus
Focus: Point where pressure builds up
Epicenter: Above focus on ground level
Hazard of earthquakes[4]
- Shake buildings
- Cause them to fall apart and collapse
- Causes damage to people and property
- Damages gas, electricity, fire
Tsunami
Underwater earthquake
Volcanic Eruption Scale
Volcanic Explosivity Index, 1-8, measures volume of gas etc
Earthquake scale
Mercalli Scale (Impact seen)
Richter Scale (Energy released)
Factors affecting damage caused by an earthquake [7]
- Energy of earthquake
- Size of area affected
- Population density
- Duration of event
- Warning
- Preparation
- Ability to cope
Impact of an earthquake [4+3]
—primary—
- Collapsed Buildings
- People injured by falling material
- Broken water/gas pipes
- Downed electricity power lines
—secondary—
- Aftershocks
- Tsunamis
- Fires
Impacts of Volcanic Eruption [3+3]
- Buildings, roads, crops destroyed by lava flows
- Death and injuries resulting directly from lava, ash and gas
- Contamination of water supplies by ash
_______ - Lahars created by mud, ash and water mixing
- Fires caused by lava and pyroclastic flow
- Economic losses, psychological trauma
Scale Tropical Cyclones
Safir Sympson Scale (1-5)
Impacts of Tropical Cyclones
physical, social, economic, environmental
Physical: Damage by wind, rain, storm surges
Social: Death, disruption of life
Economic: Infrastructure, businesses damaged
Environmental: Landslides, soil erosion, flooding
