Lecture 6/7: air quality 1 & 2

Question 1

What are pollutants in the air?

Answer 1

Substances present at concentrations above their normal ambient level. Anything in atmosphere higher than reliable standards.

Question 2

Explain what the atmosphere consists of and how it works

Answer 2

atmosphere consists of several layers, divided in layers according to major temperature changes. Gravity pushes layers of air down on the earth’s surface. –> air we breathe at sea level has higher density than air on the highest mountain.

Question 3

Name anthropogenic sources of air pollution.

Answer 3

• Burning of fossil fuels, incineration/combustion/biomass
  burning, vehicle emissions, waste decomposition
• Stationary sources – smock stacks, waste incinerators
• Mobile sources – vehicles, marine vessels, airplanes, fumes
• Agriculture – pesticides, insecticides, fertilizers

Question 4

Name natural sources of air pollution

Answer 4

• volcanoes, wildfires (exacerbated by cc), VOCs from plants, dust
• sea spray - washes pollutants out of the air BUT since it a
  source of PM - mostly salt that is whipped into the air by strong
  winds – it can also contribute to air pollution
• Methane from livestock manure

Question 5

What are different types of pollutants?

Answer 5

Primary pollutants: harmful chemicals emitted directly into the air from
natural processes and human activities.

Secondary pollutants: primary pollutants react with one another and with the basic components of air to form new harmful chemicals.

Question 6

How does carbon dioxide become a pollutant? natural and anthropogeni?

Answer 6

Natural: thunderstorms
Anthropogenic: high temperature combustion, motor vehicles, power plants.

Question 7

How does particulate matter get into the air /become a pollutant?

Answer 7

Natural: dust storms, ash from volcanoes, wildfires, se spray salt

Anthropogenic: burning of fossil fuels in vehicles and power plants.

Question 8

What is the function of good ozone?

Answer 8

• reduction of radiation by absorption
• removes almost all incoming UV

Bad:
* damage to ‘good ozone’ by GHGs leads to high levels of UV.
* UV is harmful, causing skin cancers, genetic damage and climate change.

Question 9

Ozone concentrations are the highest in the midday. Why?

Answer 9

Most sun light/UV-radiation

Question 10

What does ozone consist of?

Answer 10

Light and heat from the sun + nitrogenoxide (NO2) + Volatile organic compounds (VOCs).

Question 11

What is smog?

Answer 11

Smoke + fog. consists of ozone, nitrogen dioxide, hydrocarbons and other gases combined with solar radiation to form photochemical smog.

Question 12

How does Acid Deposition work?

Answer 12

Emission of primary pollutants –> transported –> forms secondary pollutants –>acid rain (deposition) –> Eutrophication/deforestation

Question 13

What causes acid rain?

Answer 13

release of acidic gases into the atmosphere. Gases react with water, oxygen and other chemicals to become sulphuric and nitric acid to from acid rain.

Question 14

What does a low pH mean?

Answer 14

more acidic.

Question 15

What are effects of acid deposition on vegetation/humans and infrastructure/aquatic system?

Answer 15

Vegetation:
- loss/leakage of nutrients
- corrodes protective layer of wax on leaves.
- Damage to stomata

Humans and infrastructure:
- Acidic water liberates mercury from the soil
- Agricultural food production
- Poor water quality

Aquatic system:
- High aluminium levels - highly toxic
- Fish eggs cannot hatch at low pH
- At lower pH levels, some adult fish die

Question 16

Why does transboundary transport occur?

Answer 16

Because pollutants have very low deposition velocities and secondary pollutants need time to develop.

Question 17

How are aerosols removed?

Answer 17

Aerosols are removed by wet (rain) and dry deposition

Question 18

WHat is the grasshopper effect?

Answer 18

Atmospheric distillation that transfers pollutants to the poles. When compounds that help dilute pollutants evaporate from the ground surface and is deposted in other places.

Question 19

What is the Asian Brown Cloud?

Answer 19

Giant brown cloud hanging over much of south Asia. Consists of two types of climate pollutants: partuclar matter & gases (ash, dust and smoke).

Question 20

What are effects of the asian brown cloud?

Answer 20

• poor air quality
• dimming: areasols prevent radiation from the sun while others send sunlight back into the atmosphere.
• reduces surface temperatures
• Less evaporation
• affects cloud formation
• changes rainfall patterns

Question 21

How does air move? Include outdoor and indoor in your answer.

Answer 21

outdoor:
* lgobal, large scale atmospheric circulation between atmospheric layers
* Regional - between high and low air pressures
* Local, different temperature between air and sea

Indoor:
* inside, influences temperature humidity and pollutant movement
* Natural ventilation systems
* Mechanical ventilation systems.

Question 22

What is global circulation

Answer 22

It is a consistent pattern to how air moves around our planet’s atmosphere. It is caused by the sun that heats earth more at the equater than at the poles. Result is warm light air in the tropics / heavy air near poles.

Question 23

How does regional circulation work? what is it?

Answer 23

• temperature is regulated by the energy balance of the earth
• lapse rate affects the movement of air/stability.

Question 24

Local variation? how does that work?

Answer 24

A local windsystem characterized by the movement of warm and cool air between land and water.

Induced by differences that occur between the heating or cooling of the water surface and the adjacent land surface.

Question 25

What is temperature inversion?

Answer 25

Acts as a lid to limit upward movement of air and prevents vertical mixing of pollutants.

Air is warmer closer to the earth’s surface but inversion is present: warm air above cold air. Warm air is less dense and traps air pollutants and prevents ocean cooled air near the ground from ascending enough to disperse and dilute pollutants.

Question 26

What is vertical mixing?

Answer 26

movement of air as warm air rises. Pushes ground level pollution upward to be diluted in the atmosphere. This is reduced in a stable atmosphere.

Question 27

What two areas are vulnerable to pollution by temperature inversion?

Answer 27

City located in a valley surrounded by mountains where the weather turns cloudy and cold during part of the year. Mountains and clouds block sunlight that causes air to heat and rise, and the mountains block the wind. Pollutants in the valley below will build up.

City with several million motor vehicles in an area with a sunny climate, light winds, mountains on three sides and an ocean on the other side.

Question 28

What is atmopsheric stability determined by?

Answer 28

By how much warmer a parcel of air is than the surrounding air.

Question 29

Explain the relationship between temperature and air pollution.

Answer 29

Temperature differences between air masses –> pressure differences –> atmospheric instability –> wind –> movement of pollutants.

Question 30

How does an Urban Heat Island have influence on air quality? Include in your answer what an urban heat island is.

Answer 30

Urban Heat Island = dome of heated air that contributes to the build-up of air pollution, especially during low wind days. Then you have increased wind speeds that disperse pollution.

Question 31

Explain the AQI

Answer 31

Air quality index is an index that measures hourly the quality of the air based on 3500 air quality monitoring stations in Europe. The AQI itself is a number that is assigned to a descriptive term (good, bad, moderate)

Question 32

What do VOC’s consist of?

Answer 32

GhGs - methane
Natural sources - plants
Anthropogenic sources - landfills, fossil fuels

Question 33

Human issues due to air pollution

Answer 33

Respiratory problems
Brain related diseases
Skin diseases
Problems during pregnancy

Question 34

Air pollutants with strongest evidence for public health?

Answer 34

particulate matter - cardiovascular and respiratory diseases
Ozone - breathing, asthma, lung disease
Nitrogen oxide - irritate airways, respitaroy diseases

Question 35

Talk about equity impacts of air quality.

Answer 35

Developing countries are more vulnerable to air pollution but also are exposed to larger exposure of air pollution by urban creep/urbanisations towards NIMBY situations.

Question 36

Why do developing countries produce more air pollution?

Answer 36

Environmental quality is lower priority than economic growth.

Air pollutionm is lnot law enforced

Lack of services resulting in u8ncontrolled burning of waste.

Question 37

Name the five main approaches/tools to control and reduce air pollution.

Answer 37

1. Prevention: by stronger legislations and spatial planning
2. Regulatory solutions: permits for allowable emissions and monitoring
3. market based solutions: carbon credits through products. Credits are incenctives to reduce emissions.
4. Voluntary solutions
5. Emission control technologies (filters etc… in fabrics).

Question 38

Mention the 2 objectives that are achieved through policy, environmental permits, zoning plans.

Answer 38

limiting emissions of harmful substances

preventing long-term exposure of people to pollution

Question 39

Measures in NL

Answer 39

national Air quality cooperation programme:
* national measures
* regional/local measures: zoning plans spatial measures (reducing distances between sources and vulnerable destinations).

Question 40

What doe sthe EU directive do?

Answer 40

Aims to protect human health and environment by outlining standards and objectives for ambient air quality.