Challenge of Natural Hazards (atmospheric) Flashcards
Define weather
state of atmosphere at a particular place and time
including temperature, humidity and wind speed
Define climate
weather conditions prevailing an area in general over a long period
Define insolation
amount of solar radiation reaching an area
Define latitude
angular distance north or south of the equator in degrees and minutes
Define hazard risk
degree of likelihood that harm will be caused by a natural hazard
Define natural hazard
natural event that has potential to case harm to people or area
Define economic impact
impact that affects wealth of place or income
Define environmental impact
impact that affects the natural world
The earth’s atmosphere is in constant….
motion
What is the motion of the atmosphere driven by?
energy received from the sun
Where is there more energy from the sun?
the equator
Where is there less energy from the sun?
the poles
Why does insolation vary across the globe?
curvature of earth
Explain how convection currents form
warm air rises causing low pressure
cold air sinks causing high pressure
How is wind made?
air particles move from an area of high pressure to an area of low pressure
What are the three types of convection cell that make up the global atmospheric circulation model?
polar cell
ferrel cell
hadley cell
What happens to air when it is heated and begins to rise?
- cools as it moves away from ground
- condenses as a result of colder temperatures
- clouds are formed and release precipitation
What happens to air when it is cooled and begins to sink?
- belt of high pressure created
- air becomes warmer and drier
- a cool, dry climate is created
What is the most important factor affecting climate?
latitude
Why is latitude the most important factor affecting climate?
the Earth has a curved surface so the equator receives much more compared to polar latitudes
Why does the equator receive a higher insolation?
insolation strikes at a right angle so energy is concentrated
strongly heated
What happens to warmer air at the equator?
becomes less dense so rises to higher altitudes
Why do the poles typically have cold climates?
low insolation received
results in higher pressure
air sinks to ground level and moves to equator
What does the low pressure at the equator and high pressure at the poles create?
convection current
Where on the globe is their high air pressure?
polar latitudes
Where on the globe is their low air pressure?
the equator
What are jet streams?
high altitude currents of air
Which direction do jet streams flow in?
west to east
Why do jet streams flow west to east?
Coriolis effect
Define precipitation
moisture that falls from clouds in the sky
What are the characteristics of precipitation at the equator?
rainfall is high and constant all year
Why does the equator experience high and constant precipitation?
hot air rises and cools quickly so condenses into droplets of convectional rainfall
What are the characteristics of precipitation at the intertropical convergence zone?
bursts of torrential rain
tropical storms
Why does the intertropical convergence zone experience bursts of torrential rain and tropical storms?
hot air rises and creates area of low air pressure
this triggers precipitation
‘wave’ of low pressure causes high energy tropical storms
What are the characteristics of precipitation in Western Europe?
rainfall higher on the coasts
stormy conditions
Why does Western Europe experience rainfall and stormy conditions in coastal areas?
frontal
jet stream of Atlantic
What is a frontal climate?
where cold air from poles meets hot air from tropics
What are the characteristics of precipitation at the tropics?
arid conditions
Why do the tropics experience arid conditions?
dry air descends creating a high pressure
What are the characteristics of precipitation at the polar regions?
very low precipitation
snow
Why do the polar regions experience low precipitation and snow?
cold air has a limited ability to hold water vapour
solid because of cold
What is the Coriolis effect?
circulating air is deflected depending on hemisphere
Why does the Coriolis effect deflect wind to the east?
earth rotates faster at the equator because it is wider so has further to go in a day
What is a common trait of climate at areas of high air pressure?
constant or no precipitation
What is a common trait of climate at areas of low air pressure?
torrential rain
Define tropical storm
happen in tropical regions with low pressure and strong winds
move in a spiral direction around eye of the storm
winds are powerful
rainfall is heavy
What is the eye of the storm?
the calm central area
Where are topical storms found?
area of latitude
between equator and tropics
What are characteristics of tropical storms?
powerful winds
heavy rainfall
dissipates over land
What is the local name for a tropical storm in the Atlantic Ocean?
hurricane
What is the local name for a tropical storm in the Indian Ocean?
cyclone
What is the local name for a tropical storm in the Pacific Ocean?
typhoon
Why do tropical storms dissipate over land?
tropical storms get energy from the sea so when they reach a large land mass they cannot get energy and eventually run out and dissipate
What direction do tropical storms spin in the Northern hemisphere?
anti-clockwise
What direction do tropical storms spin in the Southern hemisphere?
clockwise
Why does the spin direction of tropical storms change depending on hemisphere?
Coriolis effect
How can we categorise tropical storms?
Saffir Simpson scale
What does Category 1 mean on the Saffir Simpson scale?
74-95 mph wind
main threat to life is flooding
limited damage
unanchored boats and mobile homes
What does Category 2 mean on the Saffir Simpson scale?
96-110 mph wind
damage to buildings
roofs, windows, doors
piers
trees
What does Category 3 mean on the Saffir Simpson scale?
111-129 mph wind
names for hurricane
storm surge
significant damage
What does Category 4 mean on the Saffir Simpson scale?
130-156 mph wind
structural failure
extend inland
What does Category 5 mean on the Saffir Simpson scale?
157+ mph wind
storm surge
complete structural failure
How many categories are there in the Saffir Simpson scale?
5
What are the causes for tropical storms?
ocean depths of 70m
sea temp above 27C
low wind shear
low latitudes
between summer and autumn
How does sea temperature above 27C lead to a tropical storm?
provides heat
causes air to rise rapidly
low air pressure created
latent heat powers the storm
How does ocean depths of 70m lead to a tropical storm?
provides moisture
How does low wind shear lead to a tropical storm?
wind is constant and doesn’t vary with height so allows tropical storms to rise to high levels without being torn apart
How does being at low latitudes lead to a tropical storm?
Coriolis effect is strong enough for the storms to spin
temperatures are higher so air and sea is heated quicker so air pressure is low
How does being in between summer and autumn lead to a tropical storm?
warmest seasons to encourage warmer air to rise quicker in account of the low pressure
How do tropical storms form?
- sun’s solar radiation warms oceans in tropics
- warms to 27C
- warm moist air rises through thermals creating low pressure at centre of storm
- air cools as it rises causing condensation
- some cooled air sinks to create the eye
- air rushes in from higher pressure areas to lower pressure areas which creates storm winds
- storm rotates due to earth’s spin
Where does the sun’s solar radiation warm?
oceans in the tropics
What temperature does the sea need to be warmed to for tropical storms to form?
27
What does the 27 temperature of the sea cause when forming a tropical storm?
warm moist air rises through thermals
low pressure created at centre of storm
What happens to the air after is has been heated in the forming of a tropical storm?
cools as it rises
condensation
clouds and rain
How much does the air cool by as it rises in the forming of a tropical storm?
1 degree per 100m
What creates the eye of the storm?
some air cools and sinks
What creates storm winds of a tropical storm?
air rushes from higher pressure to lower pressure
Why causes tropical storms to rotate?
Earth’s spin
How will climate change impact distribution of tropical storms?
more areas will experience storms
Why will climate change impact distribution of tropical storms?
sea temperature rise in other places
How will climate change impact intensity of tropical storms?
significant areas will experience stronger storms
Why will climate change impact intensity of tropical storms?
global temperature increase - more energy available as fuel
How will climate change impact frequency of tropical storms?
big storms get bigger
smaller storms more common
What does the Saffir Simpson scale measure?
intensity of tropical storms
Why will climate change impact frequency of tropical storms?
global temperature increase - more energy available
What is a primary effect?
initial impact of natural event on people and property caused directly by tropical storm
What is a secondary effect?
after effects that occur indirect to impacts of natural event, on a longer timescale
What are some primary effects of tropical storms?
injuries/deaths
buildings destroyed
drowning
flooding
What are some secondary effects of tropical storms?
food shortage
homelessness
electric supplies cut off
sewage released
contaminated water
aid blocked by debris
unemployment
When do immediate responses occur?
before landfall
directly after event
What is a long term response?
preparing for future storms
repairing
Give examples of immediate responses
evacuation
medical support
shelters
water and food
recover bodies
aid from NGOs
What is a NGO?
non governmental organisation
What factors might affect immediate responses?
size of area
scale of event
preparation/protection
debris on road
What factors might affect long term responses?
density and size of area
knowledge
economy
domestic supplies
transport infrastructure
Give examples of long term responses?
rebuilding
rehousing
repairing
improvements
provide grants
What is the monitoring of tropical storms?
recording physical change
What is the predicting of tropical storms?
forecast when and where based on current knowledge
What is the protection against tropical storms?
reduce impact of storm
What is the planning against tropical storms?
response and recovery
How does monitoring reduce the impact of tropical storms?
indicate whether a tropical storm intensify
helps protection and planning
Give examples of monitoring of tropical storms
- NASA monitors weather across Atlantic in 2 unmanned aircraft called Global Hawk drones
- Global Precipitation Measurement
What are the Global Hawk drones?
2 unmanned aircraft used by NASA to monitor weather across Atlantic
What is the Global Precipitation Measurement?
satellite that monitors high altitude rain clouds every 3 hours to indicate how a tropical storm will intensify over the next 24hours
How does predicting reduce the impact of tropical storms?
predicted pathway of tropical storm
helps planning and protection
Give examples of predicting tropical storms
track forecast cones
supercomputers
GIS doppler
What are track forecast cones?
plot path of storm with 70% accuracy
What are supercomputers?
give 5 days warning and predict warning within 400km
What is the GIS Doppler?
early warnings issued by national hurricane centres
How does protection reduce the impact of tropical storms?
develops defences
Give examples of protection against tropical storms
reinforcing buildings
coastal flood defences
no build zones
How does planning reduce the impact of tropical storms?
make preparations
Give examples of planning against tropical storms
supply kits
evacuation shelters
education
battery powered weather radio
insurance
Define extreme weather
an especially severe unseasonal weather event significantly different from average weather pattern
What extreme weather is the UK likely to experience?
heatwaves
storms
What extreme weather is the UK unlikely to experience?
hurricane
tsunami
tornado
Name extreme weather types
storm surge
gale
cold
heatwave
storms
landslide
blizzards
drought
fluvial/coastal flooding
What impacts does extreme weather have?
schools and businesses close
crops damaged
livestock die
councils spend money on gritting
injuries
What impacts does gales have?
infrastructure damaged
fallen trees - blocked roads
What impacts does thunderstorms have?
fires, electrical surges, deaths, building damage
What impacts does heatwaves cause?
deaths - dehydration
transport disrupted
crops damage
livestock die
What impacts does drought cause?
crop failure
water conservation regulations
What does crop failure cause?
food prices rise
farmers lose money
rely on food imports
starvation (LIC)
What impacts does heavy rain cause?
flash floods
infrastructure damaged
crops damaged
livestock die
repairs expensive
insurance denied to high flood risk areas
What makes up infrastrucutre?
buildings
transport
communication links
energy supplies
How would you support that you strongly agree with ‘weather in the UK is becoming more extreme’?
10 hottest years in last 20 years
July 2022 record breaking temp ; 43.3C
average lentgh of more than doubled
When have the last 10 hottest years occured?
last 20 years
How long was it 34C for during the day?
6 consecutive days
How many consecutive tropical nights were there?
4