Weather Hazards - done Flashcards
Pressure belt
The regions of the earth that are dominated either by low pressure or high pressure
Surface winds
The winds flowing near the earth’s surface that we as humans experience
what is the atmospheric cell closest to the equator
Hadley cell
what is the atmospheric cell in the middle
Ferrel cell
what is the atmospheric cell furthest from the equator
Polar cell
At what latitudes of the earth does the air sink
30* and 90* (top of earth)
At what latitudes does the air rise
0* and 60*
what type of weather does high pressure areas get and why
because the air is sinking, there is no moisture in the skies so this brings dry and clear skies
what type of weather does low pressure areas get and why
because the air is rising, it cools and condenses, bringing cloud and rain
How do trade winds move and why
surface winds are experienced due to air moving from areas of high pressure to low pressure. Theses bend due to the Coriolis effect so they bend clockwise in the northern hemisphere and anticlockwise in the southern
why is it hotter at the equator
because it is directly beneath the sun whereas the angle of the poles mean the suns rays spread out so are less concentrated (lower insolation)
describe the global distribution of tropical storms
-occur between 5 and 30* N and S of the equator
- where the sea temps are high enough while still being in an area where the Coriolis effect can take place
what conditions need to be present for tropical storms to occur
- temps above 27*C
- low wind shear
- ocean depths of 60-70mm
Describe the six steps of tropical storm formation
1- the sun’s incoming solar radiation warms our ocean to the critical 27*C
2- this causes warm, moist air to rise resulting in low pressure at the centre of the storm
3- This air cools as it rises causing condensation to occur and cumulonimbus clouds to form as well as torrential rainfall
4- some of the cooled air sinks back down forming the calm eye
5- Air rushes in from the area of high pressure to the area of low pressure inside creating the winds
6- the whole storm rotates due to the Coriolis effect
why do tropical storms fizzle out when they start to hit land
- no moisture or heat
- friction
- relief of land
Structure and features of a tropical storm
- Circular shape swirling anticlockwise (in the northern hemisphere) around a central, clear eye.
- rain bands spreading out around it
- water at more than 27*C
in what three ways will climate change affect tropical storms
- distribution
- intensity
- frequency
how will climate change affect the distribution of tropical storms
will affect further away from the equator as more of the world’s oceans will be above 27*C
how will climate change affect the frequency of tropical storms
the frequency of category 4 and 5 storms will increase and 1-3 storms will decrease
how will climate change affect the intensity of tropical storms
increase
- every 1*C increase in sea temps means an increase of 3-5% wind speed
how can we monitor tropical storms
- keep an eye on cloud patterns associated with tropical storms
- Global Precipitation Measurement satellite monitors high altitude rainclouds to indicate whether a storm will intensify in the next 24 hours
How can prediction reduce the effects of tropical storms
- supercomputers can give five days warning AND
- plot the storm’s predicted path
How can protection reduce the effects of tropical storms
- reinforce buildings (shutter the windows) and bring in outdoor furniture
- develop coastal flood defences
- create no-build zones in low lying areas
How can planning reduce the effects of tropical storms
- prepare disaster supply kits
- fully fuel vehicles
- locate evacuation shelters
Types of weather hazard experienced in the UK
- Flooding
- droughts and heatwaves
- extreme cold weather
- storm events
effects of storm events in the UK
- flood and wind damage
- power supplies down
- disruption to transport
effects of flooding in the UK
- crops ruined
- landslides
- water damage
effects of droughts and heatwaves in the UK
- crop fails
- wildlife affected
- hosepipe ban
- elderly = heat exhaustion
- roads and railway lines buckle
effects of extreme cold weather in the UK
- cattle die
- injuries by slipping on ice
- crop failure
- transport and businesses shut
evidence that UK weather is becoming more extreme
- december 2010 was coldest in 100 years. warmest april was then in 2011
- 6 of the 10 hottest years on record have come in the last 20 years
why is there are relationship between general atmospheric circulation model and tropical storms
- the tropics north and south of the equator provide areas of intense low pressure so that warm, moist air is able to rise rapidly to reach high altitudes
what management strategies could be implemented after ST Jude’s storm to reduce risk of another bad event
- road levels raised
atmospheric circulation model
