2.13. Urban Air Quality Flashcards
(21 cards)
What is smog?
A mixture of fog and smoke particles
What causes smog?
The burning of coal mostly
Effects of smog
Respiratory problems and some traffic accidents
What causes photochemical smog?
The action of sunlight on nitrogen oxides and hydrocarbons (vehicle exhaust) causes a chemical reaction which results in the production of ozone (this is low level ozone which isn’t the same as high level ozone)
Effects of photochemical smog
Damage to plants, headaches, coughs, eye irritation, chest pains
Ozone is…
Good high up and bad nearby
Pollutants from vehicles
- Carbon monoxide is a colourless, tasteless, odourless, poisonous gas produced by incomplete combustion of fuel -> it’s estimated 90% of carbon monoxide emissions in the UK are from road transport
- Nitrogen dioxide reacts with hydrocarbons in presence of sunlight to create ozone and contributes to formation of particles -> 50% of total nitrogen oxide emissions from transport
- Particles or particulate matter are tiny bits of solids or liquids suspended in the air
Social impacts of CO
Affects transport of O2 around the body by blood, breathing in low levels can result in headaches, nausea and fatigue
Social impacts of nitrogen dioxide
Can inflame the lining of the lungs and impacts are more pronounced in people with asthma
Social impacts of particulates
PM10 can settle in the airway and deep in the lungs, causing health problems
Environmental impacts of nitrogen dioxide
Oxides of nitrogen can cause accelerated weatherings of buildings and acid rain.
Economic impacts of vehicles and burning fossil fuels
- Loss of productive work days
- Cost on health services
- Cost to repair buildings
Pollutants of burning fossil fuels
- Particulates or particulate matter
- Sulphur dioxide is a colourless gas with a strong odour produced when a material or fuel containing sulphur dioxide is burned -> coal and oil
Burning fossil fuels: social impacts of particulate matter
PM10 can settle in the airway and deep in the lungs, causing health problems
Burning fossil fuels: social impacts of sulphur dioxide
Short term exposure of SO2 may cause coughing, tightening or the chest and narrowing of the airways
Burning fossil fuels: environmental impacts of SO2
Produces haze, acid rain, damage to lichens, plants and corrosion of buildings
Legislation strategies
- In Scotland, local authorities can do roadside emission tests
- Clean Air Act 1956
- Road Vehicles Regulation
Technical innovation strategies
- Electric cars
- Trams
Vehicle restrictions and incentives strategies
- Car pool lanes
- Bus lanes
- In Mexico City, drivers are banned from using their cars one weekday per week, based on the last digit of their number plate
Urban air quality causes:
- Air pollution varies with time of year and air pressure. Concentration of pollutants may increase five or six fold in winter because temp inversions trap them over a city
- Particulate pollution is caused by the release of particles and noxious gases into the atmosphere. They are largely caused by the contribution of fossil fuels. A combination of dust, soot and gases are produced from vehicles and industrial processes.
- Photochemical smog is a form of air pollution that occurs mainly in cities and can be dangerous to health. Exhaust fumes become trapped by temperature inversions and, in the presence of sunlight, low level ozone forms. It’s associated with high pressure systems.
Impacts of urban air quality
Air quality in urban areas is poorer than in the surrounding countryside. This results in negative impacts on our health and environment.
