weather hazards and climate change Flashcards
what is a natural hazard?
a natural event that has the potential to cause harm to human life or property
what are some examples of tectonic natural hazards?
earthquakes
tsunamis
volcanoes
what are some examples of geomorphological natural hazards?
landslides
mudslides
what is a type of atmospheric natural hazard?
tropical storms
how does population density affect hazard risk?
more people- larger effect
how does the magnitude affect hazard risk?
the bigger the earthquake- the bigger the damage
what are the 4 layers of the earth?
crust
mantle
outer core
inner core
earthquakes and volcanoes tend to occur along…
plate margins/boundaries
what are the 3 types of plate boundaries?
constructive
destructive
conservative
can volcanoes occur along all type of plate boundaries?
no
can earthquakes occur along all type of plate boundaries?
yes
along destructive plate boundaries what type of crust subducts?
oceanic
what is an example of a conservative plate boundary?
San Andreas Fault
what type of waves do earthquakes send out?
seismic waves
what is the name of the point in the Earth’s crust where seismic waves are released from?
focus
what scale do we use to measure earthquakes?
Richter scale or Moment Magnitude Scale
what machine do we record earthquakes on?
seismeter
what is the definition of the weather?
the state of the atmosphere day to day at a particular place and time, including temperature, humidity and wind speed
what is the definition of climate?
the weather conditions prevailing in an area in general or over a long period of time
what is insolation?
the amount of solar radiation reaching a given area
what is latitude?
the angular distance of a place north or south of the earth’s equator, usually expressed in degrees and minutes
which factors affect a place’s climate?
latitude
altitude
proximity to the coastline
ocean currents
directions of prevailing winds
where do we get more energy?
in tropical areas near the equator and less at the poles
places at low latitudes close to the equator have low or high levels of insolation?
higher levels as the rays are spread over a smaller area
what level of insolation are at the poles?
higher latitude- the sun’s rays are spread over a great distance
warm air rises because it is more or less dense?
less dense than cooler air
cool air sinks because it is more or less dense?
sinks because it is more denser than warmer air
rising air creates what type of pressure?
low pressure
sinking air creates what pressure?
high pressure
what causes wind?
air particles move from areas of high pressure to areas of low pressure
what is the global atmospheric circulation model?
1) air cools and sinks, creating a belt of high pressure and a cold, dry climate
2) at about 60 degrees North and South, cold polar air mixes with warmer air and rises, creating a belt of low pressure
3) cool air sinks, creating a belt of high pressure- as it sinks, it becomes warmer and drier
4) warm air rises, creating a belt of low pressure- as the air rises, it cools. clouds form and then release precipitation. above, the air will eventually separate and move to higher latitudes 5) sun’s heat is concentrated
6) sun’s heat is spread out
where is the Hadley cell located?
between the tropics and the equator
what are jet streams?
strong, high-altitude currents of air- high altitude winds
these high altitude winds flow from…
West to East because the Earth spins and interacts with the convection cells
what is precipitation?
moisture released from the atmosphere- snow, rain, sleet, hail etc
what is precipitation like at the equator?
rainfall is high and constant throughout the year
what is precipitation like at the ITCZ?
bursts of terrential rain
what is precipitation like at Western Europe?
higher in coastal areas due to the jet streams in the Atlantic
what is precipitation like at the Tropics of Cancer and Capricorn?
hardly any precipitation
what is precipitation like at the polar regions?
low precipitation due to high air pressure
influence of global pressure and surface winds on precipitation: equator?
this is because hot air rises, cooling quickly condensing into droplets of convectional rainfall
influence of global pressure and surface winds on precipitation: ITCZ?
sometimes it creates a wave of low pressure which extends further than usual
influence of global pressure and surface winds on precipitation: Western Europe?
low air pressure (cyclones) follow the stream, bringing stormy conditions
influence of global pressure and surface winds on precipitation: Tropics of Cancer and Capricorn?
high air pressure
very arid
what does the Coriolis Effect do to wind?
due to the spin of the earth, the Coriolis Effect deflects wind to the right in the Northern Hemisphere
what is a tropical storm?
an area of low pressure with winds moving in a spiral around the calm central area called the eye of the storm
where do tropical storms mainly occur?
in the tropics- mainly the ITCZ
what type of areas are tropical storms mainly found in?
areas of low latitude between 5 degrees and 30 degrees North and South of the Equator
what are tropical storms called in the Atlantic Ocean?
hurricanes
what are tropical storms called in the Indian Ocean?
cyclones
what are tropical storms called in the Pacific Ocean?
typhoons
what season do tropical storms happen in the Atlantic Ocean?
August-October
what is the general direction of movement of tropical storms in the Atlantic Ocean?
West and then North West
what is the average annual frequency of tropical storms in the Atlantic Ocean?
1 or 2 a year
what season do tropical storms usually occur in the Indian Ocean?
December- March
what is the general direction of movement of tropical storms in the Indian Ocean?
varies with the hemisphere
what is the average annual frequency of tropical storms in the Indian Ocean?
varies with hemisphere
what season do tropical storms in the Pacific Ocean occur in>
May- Dec in the Western Pacific