Test 2 Flashcards
Importance of studying / managing air pollution (3)
*The atmosphere is extensive but not infinite
*Gas is a fluid which will transport pollutants
*Distinct relationship between contaminated air and respiratory diseases
What are the main components of the atmosphere? (9) (3 big ones)
– Nitrogen, 78%
– Oxygen, 21%
– Argon, 0.9%
– Carbon Dioxide
– Methane
– Hydrogen
– Helium
– Neon
– ozone
What is Air pollution
The presence of certain substances in the outdoor air or inside air that poses a threat to human health and/or the environment.
- “Certain Substances” may be a gas, liquid, or solid
- Airborne particles that decrease visibility is considered a form of pollution
In NL, Department of Service NL is responsible for administering
- Environmental Protection Act of 2002
- Air Pollution Control Regulations, 2004
Air Pollution Points of Consideration: (4)
- Air is in the public domain
- Air pollution is an inevitable component of modern life
- Scientific knowledge has been and must continue to be applied to the shaping of public policy
- Methods of decreasing air pollution must not increase pollution in other sectors of the environment
Three main types Lichen Classification
- Crustose (crusty): grows flat on rocks or tree trunks
- Foliose (leaf-like): attached only in spots, margins are often lobed and free
- Fruticose (shrubby): branched plant, upright or hanging
Lichens used to measure _______
Air Quality
The presence or absence of certain species of lichen
is an important biological indicator of air pollution (T/F)
T
Lichen conceptual model
Lichen community indicates
-condition of resource and,
-environmental stressors
Environmental stressors effect
-lichen communities and,
-the condition of resources
Natural Sources and Impact of Air Pollution
– Volcanic eruptions
– Forest fires
– Windblown dust
– Radon gas
Anthropogenic Sources and Impact of Air Pollution
– Energy production
* (coal and oil fired plants)
– Transportation
– Industrial activities
– Pesticide residues
Primary Air Pollutants
Either mobile or stationary
emitted directly into the air from a specific source
– have simple chemical structures
– Do not, by themselves, produce all the adverse effects of air pollution
– Examples: SO2 , H2S, NO, NH3 , CO, CO2 , HCl
Mobile Primary Air Pollutants
– Automobiles
– Airplanes
– Trains
stationary Primary Air Pollutants
– Stacks
– Coal fired power plants
Secondary Air pollutants
formed in the atmosphere by complex chemical reactions involving the primary pollutants and the constituents of unpolluted air
– Have complex chemical structures
– Responsible for most of the smog, haze and eye irritation
– Examples: SO3 , H2SO4 , NO2
Criteria
Ambient air quality (outdoors)
– limits set by regulatory agencies
– Indicates relationship between levels of exposure and short and long term health effects
– descriptive (describes the effects of pollutant when it reaches or exceeds certain levels)
– step in providing basis for air quality standards
STANDARDS
– Pollutant levels that can not be legally exceeded during a specific time in a specific geographical area
– Based on AIR QUALITY CRITERIA with an added safety factor
- In NL, must follow the Air Pollution Control Regulations, Environmental Protection Act, 2004
Air Pollution Control Regulations
- Schedule A
– Table I: Ambient Air Quality Standards
– Table II: Ambient Air Quality Dioxins and Furans - Schedule B – In-Stack Standards for Incineration and Pyrolysis
- Schedules C - Administrative Penalties for Emissions Exceedences
- Schedule G - Emission Standards for NOx
Meteorology
Science of the atmosphere and weather forecasting
Climatology
study of weather over long periods of time
Pollutants behavior in the atmosphere will
change the Meteorology and will modify the
Earth’s climate, Climatology. Meteorology
will also effect the behavior of pollutants
Atmospheric Layers (5)
Troposphere
Stratosphere
Mesosphere
Thermosphere
Exosphere
Full atmosphere extends upwards of_______ above the Earth’s surface
160 km
Troposphere
– Lowermost surface layer
– Approx.12 km in depth
– 95% of the total air mass
– Clouds are formed
– Weather patterns are developed
– Most air pollution problems occur
Stratosphere
– Stable air circulation patterns
– Extends upward to about 15 km above troposphere
– Contains most of the naturally occurring ozone
where does most of the naturally occurring ozone occur
Stratosphere
Troposphere is ___km in depth
Approx.12km
95% of the total air mass is in the
Troposphere
Clouds are formed in the
Troposphere
Weather patterns are developed in the
Troposphere
Most air pollution problems occur in the
Troposphere
Stable air circulation patterns can be found in the
Stratosphere
The dispersion of a pollutant in the atmosphere results from three mechanisms:
- air motion that transports the pollutant downwind
- wind velocity fluctuations in all directions
- concentration gradients
Air pollutants are transported, dispersed, and concentrated by
meteorological and topographical conditions
Global win circulation patterns are a result of
Temperature differences between the atmosphere at the poles and at the equator cause large scale air movement
Rotation of Earth causes the _______ _____
Coriolis force
Coriolis force
Counterclockwise motion of air in Northern Hemisphere
Hemispheric Prevailing Winds Air movement due to
uneven heating at equator vs. poles
Hemispheric Prevailing Winds
Air flowing south completes one cell back to the equator
- Air flowing north collides at 6 with cold,0̊C dense air travelling south from the north pole. Air is pushed up creating a low pressure in this area.
- Coriolis effect causes polar easterlies in the cell between 6 and the north pole0̊ and prevailing westerlies between 30̊ and 60̊
- Air movement due to uneven heating at equator vs. poles
- Warm, less dense air at equator rises and becomes less dense as it rises (this causes a low pressure at the equator)
- Air rising from the equator doesn’t move directly to the poles due to the rotation of the earth; instead causes a build up of air at 3 latitude (causing high pressure). Air0̊ sinks to the ground, some travels north and some travels south
Local Winds - Sea/Land Breezes
Sea/Land Breezes
– Differential heating of land and water surfaces
– Water warms/cools very slowly; land warms/cools rapidly
– Difference in air density causes wind
– Sea breeze in day: from cooler (more dense) air above water to warmer (less dense) above land
– Land breeze at night (reversed)
Local Winds - Mountain/Valley Winds
Mountain/Valley Winds
– Day heating of hill side causes the air density to decrease and rise
– At night, air cools on the slopes, causing air density to increase and descend down slope
Local Winds - Urban/Rural Circulation
– Components of urban area heat quickly and store heat as compared to soil and vegetation of rural areas
– Therefore urban areas are warmer in the day and retains
heat longer in the night than rural areas
– This causes light winds
Local Wind (3)
Sea/Land Breezes
Mountain/Valley Winds
Urban/Rural Circulation
Horizontal Dispersion of Pollutants depends on ____________________
depends on wind speed and direction
- As wind speed increases, the air pollutant concentration decreases
- Information on prevailing winds is useful
- Use wind rose
– Picture of wind speed and direction
Vertical Dispersion of Pollutants
- Vertical mixing of the air depends on the atmospheric stability
- A stable atmosphere is one with very little or no vertical movement of air
– No mixing
– No dispersion of pollutants vertically
Vertical mixing of the air depends on the _________________
atmospheric stability
A stable atmosphere is one with
very little or no vertical movement of air
– No mixing
– No dispersion of pollutants vertically
An unstable atmosphere is one where
the air is moving naturally in the vertical direction
– Plenty of mixing
– Dispersion of pollutants
is a stable or unstable atmosphere preferred
An unstable atmosphere is preferred to a stable one in regards to air
pollutant concentrations
Wind Velocity Profile
Movement of air near Earth’s surface is proportional
to the surface roughness
Wind Velocity Profile Factors include:
– Nature of terrain
– Location and density of trees
– Location of lakes, hills, and buildings
Planetary boundary layer
The air layer that is influenced by friction extends from a few
100’s m to several kilometres above Earth (Wind Velocity Profile)
Strong Atmospheric Stability
(super adiabatic)
is associated with unstable atmosphere
Weak Atmospheric Stability
(sub adiabatic)
is associated with stable atmosphere
Neutral Atmospheric Stability
Neutral is associated with
environmental lapse rates close to the
adiabatic lapse rate
Adiabatic process
as elevation increases, pressure
decreases which causes expansion to a lower
temperature. (assumes no heat transfer)
