Tropical Storms Flashcards
What is a tropical storm?
A violent rotating storm that occurs at the mid latitudes (i.e. the tropics), between 5-30 degrees north/south of the equator
What are the names of the 3 tropical storms (depending on where in the world they occur)?
Cyclone
Hurricane
Typhoon
Describe the distribution of tropical storms
- there is none in South America
- they occur in the tropics (cancer/capricorn)
- they form just over the sea
- occur just after the summer months in an area
What are the reasons for their distribution?
- over the sea as the warm temperatures of over 27 degrees in order to form
- just after the summer months as this is when the sea is at its warmest
- they arnt forming in the Atlantic or Antarctica oceans as the sea is never warm enough
What is the first step to forming a tropical storm?
Strong upward movement of air draws water vapour up from the warm ocean surface
What is the second step in the formation of a tropical storm?
The evaporated air cool as it rises and condenses to form towering thunderstorm clouds
What is the third step in the formation of a topical storm?
Condensing air releases energy which powers the storm and draws up more water
What is the forth step in the formation of a tropical storm?
Several small thunderstorms combine to form a giant spinning storm. Surface winds exceed 120km/h and a tropical storm is officially born
What is the fifth step of the formation of tropical storm?
Storm develops an eye where air rapidly descends. Most intense winds are found in the eye wall on the edge of the eye
What is the sixth step of the formation of topical storm?
Storm is carried across the warm ocean and continues to gather strength and energy
What is the last step in the formation of a tropical storm?
Upon landfall the storms energy supply is cut off/ friction with the land slows and weakens it. If the storm reaches warm water again it may regain some strength
Why do tropical storms rotate?
The Coriolis effect is caused by the coriolis force which deflects objects within rotating systems (the earth is tilted to storm cant go in a straight line)
How can you predict tropical storms using a map of them?
1) it shows the average track of the tropical storm so people that live in the areas which are on the path of the storm should prepare
2) says which months of the year they are likely to take place in
3) tells us the frequency of them, so if it’s likely that only 1 will taker place per year in an area then once they have had one that year they are less likely to experience another one
How do we use aircraft’s and drones to monitor tropical storms?
- they can gauge wind speeds, pressure, rainfall and snow
- they also release sensors called dropsondes which are dropped from the aircraft into the storm and send back data in real time to earth to improve forecasting models
Why are satellites of benefit for hurricane monitoring?
- they watch hurricanes from orbit, snapping visual imaging of swirling clouds and measuring weather patterns. They also track temp inside a storm, cloud heights and wind speeds
Why have computer models been incredibly useful n monitoring tropical storms?
- they can hold huge amounts of data at once rather than a human trying to remember data
- lots of data can be instantly fed into a computer which can then predict what will happen next with previous data as evidence
What scale do we use to measure tropical storms?
Saffir- Simpson Scale
How many categories are there in the SSS?
- they are 5:
1) very dangerous winds will produce some damage
2) extremely dangerous winds will cause extensive damage
3) devastating damage will occur
4) catastrophic damage will occur
5) catastrophic damage will occur
Why do category 1 storms have the highest frequency?
As they need to generate the least amount of energy therefore it takes less time for the process to take place
What are the benefits of using a simple categorisation scale such as the sss?
Easy for everyone to interpret, and therefore because people can understand it they are able to prepare for the tropical storm to the extent they need to
Why might issuing warnings lead to better preparedness and adaptation?
It means people have more time to get ready/prepare for the tropical storm to take place and hopefully that means they can lessen the effect of the storm hitting
What are the hazards associated with tropical storms?
Heavy rainfall + river flooding
Strong winds
Landslides
Storm serges
How might high wind spreads kill you?
They can make rubbish and debris fly into people or property
Trees and buildings may fall down
What is the problem with large amounts of rainfall during tropical storms?
The increased amount of water can create large waves on top of the surge which can cause damage to sea defences and adds to flood risk… people can then die by drowning
What is a storm surge and how are they hazardous?
- they are the abnormal rise in seawater level during a storm, as low pressure near eye pulls water higher and the winds pile up water and push it toward the shore.
- they are dangerous as the battering waves may erode beaches and damage buildings, also they can begin before the storm hits, cutting off escape routes
What are strong winds caused by and which areas do they mostly affect?
They are caused by friction, atmospheric pressure and air warming. They mostly affect coastal areas as they often get stronger wind speeds.
What are landslides and how are they formed?
A mass movement such as rock, earth, debris down a slope. They are formed when the force of gravity acting on a slope exceeds the resisting forces of a slope, the slope will then then fail and a landslide occurs
What are the areas at higher risk of landslides and why?
Mountainous areas, places with saturated soil and course soil and areas that lack vegetation. This is because there is less friction in steep areas. Happen in saturated soil areas as the base of the slope gets eroded and gravity pulls it down
What is heavy rainfall and how is it formed?
High amounts of rainfall in a short period of time, accompanied with short warning times. Formed when the volume of water exceeds the maximum capacity of a river so it overflows.
What areas are at higher risk of flooding and why?
Areas at the bottom of a hill, as water runs down hill quickly and gathers at the bottom. Urban areas, as grown is impermeable so water cant sink into the soil. Areas with poor drainage systems
Give an example of heavy rainfall and high winds caused by a tropical storm:
Hurricane Ida, Louisiana USA
29th August
It brought wind speeds of 277km/h and between 120 and 250 mm of rainfall
