hazards key terms Flashcards
(51 cards)
what is a geophysical hazard?
potentially damaging natural event which may cause the loss of life or injury, property damage, social and economic disruption, or environmental degradation
what is a atmospheric hazard?
potentially damaging natural event associated with changes in atmospheric hazards
what is a hydrological hazard?
extreme events associated with water occurrence, movement and distribution
what is hazard perception?
the way in which an individual or a group view the threat of a hazard event and this ten influences their actions
what is 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
what is prediction?
the ability to give warnings so that action can be taken to reduce impacts - improved by monitoring, information sharing and communication technologies
what is adjustment/ adaptation?
attempts by individuals and communities to live with hazard events and reduce their level of vulnerability
what is mitigation?
actions taken to help reduce or eliminate long-term risks caused by hazards
what is resilience?
the sustained ability to respond to, withstand and recover from the effects of natural hazards
what is risk sharing/ 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
what is hazard frequency?
how often a hazard occurs- generally smaller hazard occurs more frequently and larger hazards occur less frequently
what is hazard intensity?
the measurement of the impacts of the hazard on a place (e.g Mercalli scale)
what is magnitude?
an assessment of the size of an event (the amount of energy released)
what is hazard distribution?
the pattern of where each hazard types most likely to occur (and areas which don’t experience these)
what is lack of development?
is related to increase in economic output (wealth) coupled with improvement in social and political welfare of people within a country
what is the parks model?
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
what is the 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
what is the plate tectonic theory?
the theory that Earths outer layer is divided into several plates that move over the mantle; the rocky inner layer above the core
what is 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
what are 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
what is 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
what is 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
what is 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
what are convection currents?
heart from the earth’s core is transferred to the mantle. rock, close to the core, is heated as 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, process then repeats