Air pollution

How to measure the degree of Air

Pollution in HK?

Air Pollution Index (API)

How the API works

The API converts the levels of air pollutants measured at each air quality monitoring station into an index from 0 to 500

2 types: General (11)/Roadside stations(3)

The APIs of each station are released every hour

General VS Roadside stations

Central/Western

Eastern

Kwai Chung

Kwun Tong

Sha Tin

Sham Shui Po

Tai Po

Tap Mun

Tsuen Wan

Tung Chung

Yuen Long

Causeway Bay

Central

Mong Kok

Sources of air pollution

1. Generating electricity

high usage of electronic devices, such as air-conditioners, televisions

Commercial offices and industrial buildings require to use large amount of electricity

By burning coal, carbon dioxide is released.

2. Transportation

Comprehensive transport network with different modes of transport

Large population uses transport every day

Large amount of fossil fuel is needed, such as gasoline, diesel fuel, etc.

Release of carbon dioxide

3. Industrial processes

Using machines in factories require use of electricity for manufacturing or some burning processes.

Release of carbon dioxide.

4. Agriculture activities

Use of chemical or natural fertilizers for farming

Nitrogen oxide and methane will be released.

5. Waste disposal

Including solid waste such as construction waste, kitchen waste, organic waste, etc.

Most of them are dumped at landfills

Accumulation of waste at landfills will release methane.

Large amount of garbage each year.

6. Regional pollution (PRD)

Winter offshore wind in Hong Kong.

The wind brings the pollutants to Hong Kong.

Record of high API in Hong Kong winter.

How to tackle Air pollution problem

in HK?

Institutional effort...

The main strategies:

Control emissions from motor vehicles, power plants and industrial and commercial processes locally.

Working with Guangdong Provincial Authorities to implement a joint plan to tackle the regional smog problem.

A1. Reducing Emissions from vehicles (diesel

vehicles)main causes of high concentrations of RSPs and NOx at street level

adopt tighter fuel and vehicle emission standards:

adopt cleaner alternatives to diesel where practicable;

control emissions from remaining diesels with devices that trap pollutants;

strengthen vehicle emission inspections and enforcement against smoky vehicles; and

promote better vehicle maintenance and eco-driving habits.

to incentivise early replacement of old diesel commercial vehicles that up to the standard of Euro IV

to encourage the use of environment-friendly petrol private cars and commercial vehicles through tac concession;

to introduction a concessionary duty of $0.56 for Euro V diesel.

Additional measures (2007-

2008)

EffectivenessCompared with 1999, the roadside concentrations of the major air pollutant had been reduced by 22% and 23% (2008)

Taxis operating on liquefied petroleum

gas (LPG) were introduced as

cleaner alternative to replace diesel

taxis

A2. Cleaning the Air at street level

Cleaner alternatives to diesel

Controlling emissions from diesel

retrofit their vehicles and buses with catalytic converters

B. Reducing Emissions from Industrial Sources and Power

Plants

Limiting the sulphur content of industrial fuel --> reduced sulphur dioxide pollution to very low level

C. Action Blue Sky campaign (7/2006)

Organized by the Environmental Protection Department

Campaign slogan:

“Clean Air for a Cool Hong Kong”

D. Ban idling vehicle enginesIlegal for any driver to leave their engine running of they get out of their vehicle

Fines: HK$700

Other NGOs’ force...

Clear The Air Hong Kong

Energy - Aim to reduce harmful pollutants from the power station emissions.

Idling Engines - decided to lead a ban on idling engines across Hong Kong to be tabled to Legco.

Indoor Air Quality (IAQ) - Free IAQ assessments for the schools to be extended; the first campaign started April 2008.

Town Planning - Urge Electronic Road Pricing (ERP) to auto-regulate urban traffic density.

Definition of air pollution

Pollutants emitted to the atmosphereBy human activityE.g. CO, CO2, SO2, …

Impact of air pollution

1. Global warming

2. Acid deposition

3. Ozone depletion

4. Smog

5. Heat island effect

A. Global warming

Gradual increase in the average global temperatureSince mid-20s centuryIncreased by 0.74C in the past

decade

Impact on atmosphere

1. Global temperature

Warmed up by 0.74C in the past 100 years

2. Regional distribution of precipitation

A. Rising temperature -> melting of ice caps -> increase the amount of water for water circulation -> more rainfall in some moist tropics and high latitudes

B. Rising temperature -> greater evaporation rate -> few rainfall in some dry regions at mid-latitudes and semi-arid tropics

3. Extreme weather

E.g. Tropical cyclonesHeat wavesCold spellFloodDrought

4. Climate belts

Tropical areas expand to the temperate regionTemperate areas shift polewardShrink of polar region

Impacts on biosphere

1. Corals

Warmer ocean waterAlgae dead on coralsCorals are bleachedDeath of corals

2. Biodiversity

Some may extinctSome may be moreFood chain is disturbedStability is lowered

3. Desertification

Higher evaporation rateSoil moisture deficit increaseUnfavourable to vegetation

growthDesertification is intensified

4. Hill fire

Reduce the total are of vegetation

5. Shift of vegetation pattern

With increasing temperature and soil degradationWith decreasing rainfallTropical rainforest changes to

savannaSize of desert expandForests expand to polarward and into

higher altitudesSphere of tundra shrink

Impacts on hydrosphere

1. Glacier retreat2. Melting of sea ice3. Disruption of ice shelf, ice

sheet4. Melting of permafrost(CH4)5. Ocean acidification

Impacts on lithosphere

1. Rising sea level

Higher temperature -> melting of ice and snowHigher temperature ->

expansion of sea water-> rising sea level-> inundate low-lying coastal

regions and islands

2. Salinization

Due to intrusion of sea waterAnd salinization of groundwater

supply

3. Wave erosion

B. Acid deposition

Formed by sulphuric acid and nitric acid

Environmental impact

1. Leaves will be destroyed -> hinder photosynthesis2. Toxic metals harm roots.

1. increase acidity of lake water2. Bio-magnification3. Food chains are destroyed

Social economic impacts

1. Respiratory diseases, such as asthma, cough, headache2. Food poisoning3. Contamination of water

resources4. Unemployment, such as

farmers, fishers

3. Ozone depletion

Definition

Reductions in the amount of ozone in the stratosphere

Reduction of approximately 5% detected from 1979 to 1990

Discovered by James Lovelock (At English Scientist)

Causes1. The presence of chlorofluorocarbon compounds (CFCs)

2. Chlorine-containing source gases

3. Dissociate under UV lights

4. Releasing chlorine atoms

5. Catalyze ozone destruction

ConsequencesNegative

- Increased UV near the surface

- Human health (cancer, sunburn)

- Agricultural activities (bacteria)

- Global warming

Positive

- Production of Vitamin D

PoliciesMontreal Protocol (1987)

UN:World Ozone Day (1994)

Local Government effort (USA: The United States Environmental Protection Agency)

The Climate Action Network (CAN): linking up all NGOs dealing with OP over th e world (eg. Institute of Environment and Development of China)

4. Smog

Smoke + fog

Impacts of smog

1. Lower visibility2. Adversely affect tourism3. Health

5. Heat island effect

Difference between urban air temperature and rural

Urban area is hotter

Impacts of heat island

1. Energy

-consume more electricity

2. Health

-heat related diseases: dengue fever

3. Water resource

4. Urban climate

-high temperature

-decrease wind speeds