Chapter 3 - Weather Hazards

Question 1

What’s global atmospheric circulation

Answer 1

Helps to explain the location of world climate zones and the distribution of weather hazards

Question 2

What’s the most important influence on worldwide variations in climate/ tell me about how sunlight affects the climate

Answer 2

Latitude, because the curved surface of the earth, the equator receives much higher insolation that the polar latitudes - where’s as at low latitudes, sunlight is more highly concentrated

As a result, air at the equator is heated strongly - it becomes less dense and rises to high altitude, this creates a global climate zone of low pressure, the equatorial zone
After rising, the air spreads out and begins to flow towards the north and south poles

In low insolation received at polar latitudes result in colder, dense air and high pressure

As the air sinks towards ground level, it spreads out and flows towards the equator

Question 3

What’s a convection cell

Answer 3

The low pressure belt at the equator and the high pressure belt at the poles provides the basis for a simple convection cell to operate

Question 4

What’s the Hadley cell

Answer 4

The areas of high pressure at the tropics of cancer and Capricorn, air sinks towards the ground there and as it descends the air warms. The result is high pressure and hot, dry desert conditions. This circulation of air between the tropics and equator is the Hadley cell

Question 5

What’s global circulations

Answer 5

Involves 3 cells Becuase the earth rotates on its axis , the movement generates strong, high altitude winds which wrap around the planet like belts

These winds flow towards the east, as the earth spins and interact with the convection cells.

Question 6

What are jet streams

Answer 6

Strong high altitude currents of air

Question 7

What are the global convection cells

Answer 7

Polar cell, Ferrel cell, Hadley cell

Question 8

How is precipitation influenced by global pressure and surface winds at the equator

Answer 8

Rainfall is high and constant throughout the year near the equator. As hot air rises, it cools slightly. Water vapour is converted into droplets of conventional rain

Question 9

How is the intertropical convergence zones precipitation affected by global pressure and surface winds

Answer 9

It’s a low pressure zone, air rises and triggers bursts of torrential rain. Sometimes the area grows a wave of low pressure which extends further than usual. Tropical storms develop along these waves. Once they gain energy, they can travel even further away from the equator

Question 10

How is rainfall affected by coastal areas in Europe by global pressure and surface winds

Answer 10

Rainfall often higher due to movement of the jet stream over Atlantic. Rain bearing weather systems called depressions or cyclones follow the jet stream, often bringing stormy conditions to the uks west coast

Question 11

How is rainfall affected in the tropics by global pressure and surface winds

Answer 11

Rainfall is often low around the tropics of Capricorn and cancer. Dry air descends there as part of the Hadley cell, resulting in arid conditions

Question 12

Tell me how rainfall is affected in the polar regions by global pressure and surface winds

Answer 12

Precipitation is low in polar regions and mainly falls as snow. The cold air has a limited ability to hold water vapour

Question 13

What are tropical storms

Answer 13

Are a natural hazard

Occurs when warm air rises to create an area of intense low pressure, much lower than depressions experienced in the U.K.. As the warm moist air reaches high altitudes, powerful winds spiral around the calm central point , creating the “eye of the storm” and the warm air cools and condenses into heavy rainfall and thunderstorms

Question 14

How are names of tropical storms made

Answer 14

They are alphabetical and alternate in gender, more recognisable and engaging for public when given names rather than coordinates. Names repeat every 6 years unless a large loss of life or cost In damage would make it insensitive to repeat it

Question 15

What are tropical storms called

Answer 15

They are called differently deepening on their location

Hurricanes in Atlantic and eastern Pacific oceans

Typhoons in the west of the North Pacific Ocean

Cyclones in the Indian and South Pacific oceans

Question 16

Where do tropical storms occur

Answer 16

In the tropics where the intertropical convergence zone is - broadly south of the tropic or cancer and north of the Tropic of Capricorn

Found in areas of low latitude - between 5 and 30 degrees north and south of equator

Here a higher insolation means temperatures are higher than at the poles

Question 17

Tell me the conditions for a tropical storm to form

Answer 17

Sea must be about 27 C and a depth of 60-70 Metres

This provides the heat and moisture that causes the warm air to rise Rapids in this low pressure region. Latent heat is then released which powers the tropical storm . The warmest seasons are between summer and autumn which is most typical for tropical to develop

There is low wind shear (which remains constant and does not vary with height) so that the tropical storm clouds can rise to high levels without being torn apart

They don’t develop on along the equator because the Coriolis effect is not strong enough here for strong tropical storms to spin

Question 18

How does a tropical storm form

Answer 18

Air is heated above the surface of warm tropical oceans, the warm air rises rapidly under the low pressure conditions

The rising air draw up more air and large volumes of moisture from the ocean, causing strong winds

The Coriolis effect causes the air to spin upwards around a calm central eye of the storm

As the air rises, it cools and condenses to form large, towering cumulonimbus clouds which generate torrential rainfall. The heat given off when the air cool powers the tropical storm

Cold air sinks in the eye, therefore there is no cloud, so it’s drier and much calmer

The tropical storm travels across the ocean in the prevailing wind

When the tropical storm meets land it is no longer fuelled by the source of moisture and heat from the ocean and so it loses power and weaken, the air pressure and temperature rise. Wind and rainfall subside

Question 19

Why does a tropical storm spin

Answer 19

The Coriolis effect bends and spins the warm rising air.

Hurricanes in the northern hemisphere bend to the right, which causes the clouds to swirl anti clockwise whereas cyclones in the Southern Hemisphere swirl In a clockwise direction

Question 20

What direction do tropical storms travel

Answer 20

Travel from east to west due to the direction the earth spins

When they hit land, they lose their energy source from the sea that powered them - friction also allows them to slow down and as they slow doe they change direction

Question 21

How long does an average tropical storm live for

Answer 21

1-2 weeks

Question 22

What is the Coriolis effects

Answer 22

Wind blows from areas of high pressure to areas of low pressure, as the earth rotates it causes wind to bend because the earths curvature and so the earth spins faster at the equator and difference in speed means that wind bends as it blows across the earth

Question 23

How could climate change alter the conditions that cause tropical storms to formed

Answer 23

As the temperature increases, sea levels will rise due to thermal expansion. The impact of rising sea levels will mean storm surges are expected to become higher

A Warmer atmosphere will mean the air can hold more moisture. So heavy rainfall is expected to increase. Therefore flooding during a tropical storm would be more destructive

Question 24

How does climate change affect the intensity of tropical storms

Answer 24

There is evidence of warmer oceans and the intensity of tropical storms - and expected to become more severe

Every 1 C increase in sea surface temperatures will mean a 3-5 percent increase in wind speed

Question 25

How does climate change affect the frequency and distribution of tropical storms

Answer 25

Frequency to stay same or decrease By will be more severe storms, and category 1-3 storms will decrease The regions where tropical storms are experienced are not expected to change significantly as a result of climate change

Question 26

How does the uncertainty of tropical storms change due to climate change

Answer 26

Predicting impacts is unreliable as the rate of and impact of climate change in the future is uncertain Potential risk to like and property has already increased due to population growth and building in coastal locations even without factoring in climate change

Question 27

What are the effects of a tropical storm

Answer 27

Landslide and tornadoes can also be caused by tropical storms Wind speeds are at least 119kM an hour they can demolish houses across ,whole towns and villages, electricity power lines Flooding caused by heavy rain from storm surges - can be up to 5 metres Aid is hampered as roads are flooded Water supplies can be contaminated with seawater, sewage and industrial waste - increase risk of waterborne diseases such as cholera

Question 28

How are tropical storms measured

Answer 28

Measured using the saffir-Simpson hurricane wind scale It's based on when's speed The higher the category scale 1-5 the higher the intensity of a tropical storm

Question 29

What are the responses to a tropical storm

Answer 29

Evacuation to higher ground or even to emergency storm shelters Distributed emergency food and water To survivors, aid may be hindered if roads have become blocked by debris or fallen trees or flooded.

Question 30

Tell me about a wind category 1 storm

Answer 30

Some damage to well constructive roofs, large branches of trees will snap, power outraged could last several days Very dangerous winds will produce some damage

Question 31

Tell me about a wind category 2 storm

Answer 31

Well constructed roofs will have major roof damage, shallow rooted trees will be snapped or uprooted Near total power is lost and power outrages could last from several Days to weeks Extremely dangerous winds will cause extensive damage

Question 32

Tell me about a wind category 3 storm

Answer 32

Devastinh damage, major damage to roof or removal Electricity and water will be unavailable for several days to weeks after storm passed

Question 33

Tell me about a wind category 4 storm

Answer 33

Catastrophic damage will occur Loss of most of the roof structure Most trees will be snapped or uprooted Most of area will be uninhabitable for weeks or months

Question 34

Tell me about a wind category 5 storm

Answer 34

Catastrophic damage will occur Frames of houses destroyed, total roof failure, fallen Trees, power outraged will last for weeks week months and area will be uninhabitable for weeks to months too

Question 35

What's sustainable development

Answer 35

After initial relief effort, these are long term repainted that take longer to implement but have longer lasting impacts Projects include repairing damage to existing buildings, infrastructure and businesses Investing In methods of protection and prediction in storms such as a new warning system for storm surges or new sea defences

Question 36

How what the speed to start long term responses depend on

Answer 36

The wealth of country How much destruction Help available from other countries, organisations and charities

Question 37

What does monitoring tropical storms mean

Answer 37

Allows predictions to be made which can save lives and reduce impact

Question 38

How can satellites monitor tropical storms

Answer 38

There's a classic cloud pattern associated with tropical storms that satellites can monitor The global precipitation measurement satellite measure preoccupation every 3 hours between latitudes 65 degrees north and south of equator to identify the high altitude rainclouds

Question 39

How can aircraft monitor tropical storms

Answer 39

They can collect air pressure, rainfall and wind speed data, they release drop sondes (sensors) which send measurements every second by radio back to the aircraft On board radar and microwaves help scientists to understand more about the formation of tropical storms to improve forecasting models

Question 40

Can tropical storms be predicted

Answer 40

All available weather data is fed into supercomputers which run models to predict the path and intensity of tropical storms Can now give 4 days warning and a location within 400km accuracy Cyclone Phailin predicted and 1.2 million evacuated

Question 41

What's the problem with evacuation

Answer 41

Is costly and time consuming, especially if the path of tropical storm does not pass area they live

Question 42

How can we protect ourselves from tropical storms

Answer 42

Areas can be reinforced to reduce damage caused by winds- mitigation Install hurricane straps between the roof and walls Install storm shutters on Windows Install an emergency generator Tie down windborne objects Reinforce garden doors Remove trees close to buildings Coastal flood defences such as levées and floodwalls reduce impact on storm surge

Question 43

How can planning reduce risks

Answer 43

Prepare disaster supply kits Having fuel in vehicles Knowing where official evacuation shelters Storing loose objects Planning with family what to do

Question 44

What's extreme weather

Answer 44

It's damage done to societies that make these event hazardous Main types of hydro meteorological hazards: storms, flooding, drought and extreme cold weather

Question 45

Tell me about general flooding in the U.K.

Answer 45

Caused by heavy rainfall or strong waves brought by a depression May also trigger landslide as a secondary hazard

Question 46

Tell me about coastal flooding

Answer 46

A deep depression brings a storm surge to a major river estuary Strong winds funnel coastal water into the mouth of a river In 1953, 300 people died when a storm surge hit the Thames estuary

Question 47

Tell me about river flash flooding

Answer 47

High intensity Rainfall brings flash flooding especially on steep slopes

Question 48

Tell me about slow onset river flooding

Answer 48

A long period of steady rainfall gradually saturates the catchment soil

Question 49

Tell me about surface water flooding

Answer 49

Intense rainfall collects in hollows and depressions where homes are located

Question 50

Tell me about storm events in the uk

Answer 50

U.K. Regularly hit by depressions which bring heavy rainfall and trigger river floods

Question 51

Tell me about tornadoes in the uk

Answer 51

A tornados is a rotating column of spiralling sit whose formation is triggered by strong heating of the ground

Question 52

Tell me about droughts in the uk

Answer 52

It's an extended period of low or absent rainfall relative to expected average for a region 15 days with less than 0.2mm of rain means there may be insufficient moisture for average crop production

Question 53

Tell me about extremes of cold water in the U.K.

Answer 53

Cold conditions take over if depressions are not passing over the uk as usual Risks include Frost - crops and cattle may not survive below -10 C Freezing conditions mean trains can be cancelled Blizzard conditions - transport grinds to a halt, creating costly airline delays

Question 54

How could we manage the risk of extreme weather in uk

Answer 54

Use Twitter and other social media to alarm others of damage Future proof their homes by very sensibly having stone tiles rather than carpets in their ground and basement rooms

Question 55

What are bottom up actions

Answer 55

Actions people take to increase their human resilience to hazards

Question 56

What are top down actions

Answer 56

Taken to protect communities

Question 57

What top down actions can we take for droughts

Answer 57

A hose pipe ban can be put in place - even send out hose pipe patrols Water supplies to houses are turned off and members of public take their then queuing in the street at standpipes Encourage people to have a water meter fitter and do more to repair old water pipes

Question 58

What top down actions can be taken to storms

Answer 58

The U.K. met office is trying to improve weather predictions Severe weather warnings can be issued using social media and social media Airlines and rail companies cancel their services when there are very strong winds

Question 59

What top down actions can be taken for floods

Answer 59

The Thames barrier was completed to avoid storm surges The environment agency constantly monitors ground moisture levels in river basins so EA can make accurate flood predictions to allow evacuation Any new housing on floodplains face higher insurance bills - deter construction

Question 60

What top down actions can we take for cold water

Answer 60

Clear roads of snow and ice Make announcements in media warning people to take care while in blizzard conditions Charities for elderly raise awareness about more health risks for old people in cold conditions - work to raise public awareness of issue

Question 61

How has climate change changed storm frequency

Answer 61

There has been an increase in extreme rainfall since 1980s as the Atlantic Ocean has warmed and rain bearing depressions will be Gaining more moisture and energy

Question 62

What does temperature record tell us about drought frequency

Answer 62

U.K. Temps have increased by 1 C since 1980 - however in the graph showing temp change the spikes shown don't all correspond with drought where the spikes are a higher temp as rain deficiency is needed to

Question 63

What are the extreme weather predictions for the future

Answer 63

Some suggest a global Temp rise of 2-3 C in the 21st century If this happens U.K. Could face warmer and wetter winters - more rain bearing depressions Risk of extreme flooding and high winds will increase A global temp increase of 4-5 C would melt a lot of land and sea ice in artic, colder water would pour into the North Atlantic which would cause unknown effects but with a warmer world the U.K. Could be left facing more extremes of cold water

Question 64

Tell me about the current and predicted precipitation

Answer 64

No change in annual uk total but more winter rainfall has fallen in heavy events since 1980s But in future will become more seasonal but annual uk total will stay the Same

Question 65

Tell me about the current and predicted changes in river flow

Answer 65

The frequency and magnitude of winter river flooding has increased since 1980s Some predict uk river will flood more in future winters

Question 66

Tell me about current and future evaporation changes

Answer 66

Not sure if evaporation has increased but temp has risen by 1 C Evaporation will increase due to higher air temps causing more droughts