Hazards key terms Flashcards
(50 cards)
geophysical hazard
A natural event that may cause a loss of life and damage to building or land.
atmospheric hazard
potentially damaging natural event associated with changes in atmospheric conditions
hydrological hazards
extreme events associated with water occurrence, movement, and distribution
hazard perception
the way in which an individual or a group view the threat of a hazard event and this then influences their actions
fatalism
a view that suggests people cannot influence outcomes therefore nothing can be done to reduce (mitigate) the event or its impacts : an act of God ; people remain
prediction
the ability to give warnings so that action can be taken to reduce impacts - improved by monitoring, information sharing and communications technologies
adaptation
attempts by individuals and communities to live with hazard events and reduce their level of vulnerability
mitigation
actions taken to help reduce or eliminate long-term risks caused by hazards
resilience
the sustained ability to respond to, withstand and recover from the effects of natural hazards
preparedness
prearranged measures to reduce the loss of life and property damage through education, evacuation procedures, provision of emergency shelters and the taking out of insurance
hazard frequency
how often a hazard occurs - generally smaller
hazards occur more frequently, and larger hazards occur less frequently
hazard intensity
The measurement of the impacts of the hazard on a place ( e.g. Mercalli scale )
magnitude
an assessment of the size of an event (the amount of energy released)
hazard distribution
the pattern of where each hazard type is most likely to occur (and areas which don’t experience these)
level of development
is related to increase in economic output (wealth) coupled with improvement in social and political welfare of people within a country
Park’s model
(disaster-response curve)
a model graph to show the effects of a hazard on quality of life over a sequence of time and expected stages from pre-event to eventual recovery
hazard management cycle
the continuous process by which individuals and communities manage hazards in an effort to avoid or mitigate the impacts resulting from the hazards and learn to manage and prepare for them better over time
plate tectonic theory
the theory that Earth’s outer layer is divided into several plates that move over the mantle; the rocky inner layer above the core
crustal evolution
the rate of continental crustal growth and recycling through time and how changes in tectonic movement have influenced the rates of crustal growth and preservation
tectonic plates
the large, separately moving areas of the lithosphere that are the result of its breaking apart into seven or eight major sections (depending on how they are defined) and many minor ones
gravitational sliding
the movement downward or downslope of rock / lava in response to gravitational instability along particular slopes in unstable regions such as mid-oceanic ridges
ridge push
a proposed driving force for plate motion that occurs at mid-ocean ridges as the result of the rigid lithosphere sliding down the hot, raised asthenosphere underneath mid-ocean ridges - this push is caused by gravitational force and it exists because the ridge occurs at a higher elevation than the rest of the ocean floor
slab pull
the portion of motion of a tectonic plate that can be accounted for by its subduction and it is partly driven by the weight of cold, dense plates sinking into the mantle at oceanic trenches - the cooler sinking plate pulls the rest of the warmer plate along behind it
convection currents
heat from the earth’s core is transferred to the mantle. Rock, close to the core, is heated and so has plasticity and so it rises. When it reaches the crust it is forced sideways as often it cannot pass through the crust. The frictional drag between the convection current and the lower surface of the crust causes the tectonic plate to move. The more liquid rock then sinks back towards the core as it cools. The process then repeats.
