1.4.2 Urban Air Quality

Question 1

Examples of atmospheric pollution reduction policies

Answer 1

• ULEZ
• Public transport
• Carbon taxes

Question 2

How many Londoners die prematurely from air pollution each year?

Answer 2

Estimated 9,400.

Question 3

London Congestion Charge

Answer 3

Charge is on average £11.50 per day with high emission vehicles being charged more (on a sliding scale). Hybrid and electric cars are free.

Question 4

Benefits of the congestion charge

Answer 4

• Traffic reduced by 21%.
• Bus passenger numbers have increased by 45%.
• Cyclists have increased by 43%.
• Road traffic accidents are down by 5%.
• CO2 and NO2 emissions down by 12%.

Question 5

ULEZ

Answer 5

Ultra-low emission zone

Question 6

London ULEZ

Answer 6

A specified area of London where the most polluting vehicles are required to pay a daily charge. - Introduced in February 2008.

Question 7

How much does the London ULEZ cost?

Answer 7

Small vehicles will pay around £12.50 per day but heavier polluting vehicles will pay around £100 per day. This is an addition to the congestion charge.
24h per day, 7 days per week, 365 days per year.

Question 8

How many vehicles are affected daily by the London ULEZ?

Answer 8

An estimated 68,000 vehicles.

Question 9

Boris Bikes

Answer 9

One of the largest bike hire schemes in Europe, having started operations in 2010.
Been used almost 92m times in the last 10 years.
Expanded (doubled) from 350 docking stations to 780!

Question 10

Hybrid buses

Answer 10

• There are 3,773 hybrid, 316 fully electric and 10 hydrogen buses in London. – Making up over 1/3 of all buses in London.

Question 11

Benefits of hybrid buses

Answer 11

• These buses are quieter, cleaner and more fuel efficient than standard diesel buses, hybrids reduce emissions of CO2 by at least 30% compared with conventional buses.
• Reduced CO2 emissions by around 98,000 tonnes per year.

Question 12

Plug-in car grant

Answer 12

Government incentive for buying of ULEZ vehicles.
This is automatically deducted from the price of the vehicle.
Scheme favours electric cars.

Question 13

Pros of electric cars

Answer 13

• No Co2 or greenhouse gas emissions
• Government incentives
• No congestion charge or ULEZ
• Free road tax

Question 14

Cons of electric cars

Answer 14

• Limited infrastructure
• Higher initial costs
• Higher mantenance costs

Question 15

Controlling vehicles: Athens

Answer 15

The city declared an area of 2.5km2 in the centre, traffic free.

Question 16

Controlling vehicles: British CBDs

Answer 16

Many British towns and cities have pedestrianised in their Central Business Districts (CBD).

Question 17

Controlling vehicles: London

Answer 17

ULEZ and congestion charges have attempted to control vehicle numbers.

Question 18

Controlling vehicles: Mexico

Answer 18

“Hoy no Circula” (don’t drive today) – Council policy that bans all vehicles from being driven in the city on one weekday per week, the vehicle registration number determining the day.

Question 19

Persuade the use of public transport

Answer 19

e.g. Manchester’s development of a tram system, the development of bus-only lanes into city centres. Park and Ride schemes, car-sharing schemes.

Question 20

Zoning of industry

Answer 20

Industry is placed downwind in cities and planning legislation has forced companies to build higher factory chimneys to emit pollutants above the inversion layer.

Question 21

Why is particulate pollution more prevalent in urban areas?

Answer 21

The concentration of particulates in urban areas is much higher than in rural areas.

Question 22

What are the sources of particulates in urban areas?

Answer 22

• Vehicle exhausts – they produce very fine particulates. About 80% of fine particles in urban areas are from vehicle exhausts.
• Burning of refuse, cigarettes and fuel (e.g. coal) – this produces both fine and coarse particulates (e.g. sulphates, nitrates, soot and ash).
• Construction, mining and quarrying – these activities produce coarse particulates (e.g. tiny fragments of rock, brick and cement dust).
• Plants and moulds – generate coarse particulates (e.g. pollen and mould spores).

Question 23

What are particulates?

Answer 23

Tiny pieces of solids and tiny droplets of liquids floating in the air.

Question 24

What is photochemical smog?

Answer 24

Pollutants such as nitrogen oxides, sulphur oxides and hydrocarbons come from burning fossil fuels (e.g. in vehicles and factories).

When these pollutants come into contact with sunlight, the UV light causes them to break down into harmful chemicals (e.g. ozone) which form photochemical smog.

Question 25

Where is photochemical smog most prevalent?

Answer 25

It is more common in places with hot and sunny climates because there’s more sunlight.

Question 26

What can photochemical smog cause?

Answer 26

Health problems such as breathing difficulties (cough, shortness of breath), respiratory disorders (e.g. asthma) and headaches.

Question 27

Case study: Air quality in London

Answer 27

• In 1952, London experienced a thick fog “Pea Souper”. It lasted for 5 days, and 4000 people died (either from lung problems or from falling into the Thames because the fog was so thick).
• Following the 1952 Pea Souper, the UK government created the Clean Air Act 1956, which introduced smoke-free zones into urban areas.
• In the 1990s, very tough regulations were imposed on levels of airborne pollution.
• Local councils in the UK are now required to monitor pollution in their areas and establish Air Quality Management Areas where levels are likely to be exceeded.

Question 28

How many Londoners - on average - die prematurely from air pollutants each year.

Answer 28

9,400

Question 29

How does legislation help to tackle urban air pollution?

Answer 29

Laws aim to reduce pollution by limiting emissions and setting air quality standards. For example:
- The UK Clean Air Acts of 1956 and 1968 reduced domestic pollution by introducing smoke control areas where only smokeless fuels could be burned, and reduced industrial pollution by introducing the use of tall chimneys (which mean that pollutants are dispersed higher in the atmosphere, making them less harmful to people in the city).

• The Road Vehicles Regulations reduce exhaust emissions by ensuring cars pass an emissions test in their MOT.
• In Scotland, legislation allows local authorities to do roadside emission tests, where they can issue fines if the vehicle fails. Throughout the UK, local authorities can issue fines to people who leave their engines running unnecessarily.

Question 30

How does the use of alternative fuels help to tackle urban air pollution?

Answer 30

Petrol and diesel are replaced with cleaner fuels that pollute less. For example:
- Biofuels (e.g. bioethanol and biodiesel) are produced from plants. They can directly replace petrol and diesel and have lower particulate emissions. However, growing the crops needed to make biofuels can reduce biodiversity, e.g. biofuels like corn-based ethanol need a lot of land to grow, which means clearing other vegetation.

• Liquified Petroleum Gas (LPG) is a gas produced from fossil fuels that has lower emissions than petrol or diesel. However, cars have to be converted to use LPG, and service stations have to be adapted to distribute it.
• Electric vehicles have lower emissions because they run off batteries, rather than conventional fuel. Electric vehicles need recharge points, and producing and disposing of the batteries can cause environmental problems.