8.3 Urban Air Pollution (DP IB Environmental Systems & Societies (ESS): HL): Flashcards

False.

NOx and SO₂ are mainly produced by human activities like burning fossil fuels, not by natural sources.

In Los Angeles, high levels of ozone (O₃) pollution are mainly due to a large number of vehicles and sunny weather.

Beijing, China, is known for experiencing severe PM2.5 pollution mainly due to coal burning and industrial activity.

Air pollution management strategies are measures designed to reduce harmful emissions and improve air quality in urban areas.

The main aims are to reduce harmful emissions and improve air quality in urban areas.

Air pollution management strategies focus on reducing the sources of pollution, promoting cleaner technologies, and encouraging sustainable urban living.

Encouraging sustainable urban living reduces the demand for polluting activities and helps cities maintain cleaner air over the long term.

An emission zone is an area where only vehicles meeting specific environmental standards are allowed, to reduce pollution.

A catalytic converter is fitted to car exhaust systems to reduce harmful emissions.

Catalytic converters convert harmful pollutants like nitrogen oxides and carbon monoxide into less harmful gases such as nitrogen and carbon dioxide.

True.

Trees absorb carbon dioxide and trap particulate matter, helping to filter pollutants and improve urban air quality.

Green walls and green roofs help improve air quality by filtering pollutants from the air.

Cities can promote renewable energy sources such as wind or solar power and improve public transport systems to reduce car usage.

False.

Low Emission Zones restrict high-polluting vehicles from entering city centres to reduce air pollution.

Acid rain is rainfall with a pH lower than normal rainwater, usually as a result of pollution by sulphur dioxide and nitrogen oxides.

The two main gases responsible for the formation of acid rain are sulphur dioxide (SO₂) and nitrogen oxides (NOₓ).

Rainwater is naturally slightly acidic, with a pH between 5 and 5.5. Acid rain has a pH lower than this.

Wet deposition refers to acidic precipitation falling as rain, snow, or fog, while dry deposition involves acidic dust and gases settling on surfaces.

Nitrogen oxides are mainly produced from vehicle exhausts, whereas sulphur dioxide is primarily produced by burning fossil fuels.

Nutrient leaching is the process where essential nutrients are washed out of the soil by acidic deposition, reducing their availability for plants.

Acid rain leaches essential nutrients from the soil, causing nutrient deficiencies, reduced plant growth and lower ecosystem productivity.

Acid rain can mobilise toxic metals like aluminium, damaging plant roots and making it harder for plants to absorb water and nutrients.

Coniferous forests, such as pine and spruce, are sensitive because they have shallow root systems and thin bark, making them more vulnerable to acid rain damage.

Solubilisation of aluminium is when acid rain causes aluminium, normally bound in soil, to dissolve and enter water bodies.

Acid rain reduces the availability of calcium needed for building exoskeletons, making it harder for aquatic invertebrates to develop and maintain their shells.

Fish exposed to acid rain may have gills coated with aluminium, making it harder for them to breathe.

Acidic deposition is the process by which acidic components from the atmosphere settle on Earth’s surface, either as wet (rain, snow, fog) or dry (dust, gases) forms.

True.

Acid rain damages leaves and needles, weakening plants and increasing their susceptibility to disease and environmental stress.

The chemical is calcium carbonate (CaCO₃), which reacts with acids in acid rain, leading to erosion.

The Taj Mahal in India has shown signs of erosion and discolouration due to acid rain.

A scrubber is a device installed in factories or power plants to remove sulphur dioxide and other pollutants from emissions before they are released into the atmosphere.

Spreading ground limestone or lime neutralises acidity in lakes and rivers, helping to restore the water's pH balance and support aquatic life.

Switching to renewable energy sources can significantly reduce emissions of sulphur dioxide and nitrogen oxides, helping to manage acid rain.

Photochemical smog is a type of air pollution formed when sunlight triggers chemical reactions between primary pollutants, producing secondary pollutants and resulting in a brown or grey haze over urban areas.

A primary pollutant is a substance directly released into the atmosphere from a source, such as nitrogen oxides (NOx) or volatile organic compounds (VOCs).

A secondary pollutant is a substance produced when primary pollutants react in sunlight, such as peroxyacyl nitrates (PANs) and tropospheric ozone, which contribute to smog formation.

Photochemical smog forms when sunlight triggers chemical reactions between primary pollutants, forming secondary pollutants.

The two main primary pollutants are nitrogen oxides (NOx) and volatile organic compounds (VOCs).

Peroxyacyl nitrates (PANs) and tropospheric ozone are examples of secondary pollutants formed in photochemical smog.

A temperature inversion leads to pollutants being trapped near the ground, causing higher smog concentrations.

High sunlight increases the rate of photochemical reactions between pollutants, leading to more intense smog formation in cities.

A layer of warm air traps cooler air and pollutants near the ground during a temperature inversion.

False.

Windy conditions help disperse pollutants, reducing smog intensity. Stagnant air or reduced wind traps pollutants and increases smog.

An urban canyon is a street lined with tall buildings that restrict air movement, reducing pollutant dispersal and intensifying smog.

Cities in mountainous terrain, such as Mexico City, are prone to smog because mountains block wind and trap pollutants.

Tropospheric ozone is a form of ozone (O₃) found at ground level, which acts as an air pollutant and can harm living organisms and materials at high concentrations.

Tropospheric ozone damages plant cuticles and membranes, leading to reduced photosynthesis and slower plant growth, causing reduced yields in crops like wheat and soybeans.

Tropospheric ozone exposure can cause stinging and redness in the eyes of humans and mammals.

Tropospheric ozone inflames the airways, causing coughing, throat irritation, shortness of breath, and aggravating conditions like asthma and bronchitis.

Stratospheric ozone is a layer of ozone (O₃) in the upper atmosphere that protects living organisms from harmful ultraviolet radiation.

True.

Ozone accelerates the deterioration of natural fibres like cotton, synthetic fibres like nylon, and causes cracking and brittleness in natural and synthetic rubbers.

The impacts of tropospheric ozone can be transported over long distances by wind, making it a global environmental issue.

Exposure to tropospheric ozone increases respiratory and cardiovascular illnesses, leading to higher healthcare expenses and increased spending on treatments and hospitalisations.

High ozone levels can overwhelm hospitals and clinics due to a surge in patients with respiratory distress.

Tropospheric ozone can reduce economic output by causing missed workdays due to illness and by reducing agricultural yields, which impacts farmers’ incomes and increases food prices.

Disproportionate effects refer to greater negative impacts of tropospheric ozone on poorer communities, who are more exposed to pollution and have less access to healthcare.

True.

Farmworkers and outdoor labourers in polluted areas face the highest risks because they are more exposed to high ozone levels and often depend on physical labour for their income.