Air Pollution Flashcards
Pollution
Introduction of a substance or form of energy into the environment that can cause harm to the enviornment
Natural source
EX. Volcanic Ash (PM), CO2
Anthropogenic source
Fossil fuel emissions, sewage, excessive nutrients, heat
Point source
A single, identifiable source of a pollutant, exact source is known.
Easier to monitor+regulate (easy to clean)
EX. smoke stack, discharge pipe, leaking tank
Nonpoint source
Diffused and can therefore be difficult to identify, cannot be traced back to a single point of discharge. Nonpoint sources are harder to monitor and regulate. Many sources.
EX. spraying pesticides, runoff from large agricultural regions, urban runoff
Plume
The pattern a pollutant makes as it travels through the environment
Chemical composition
How toxic or harmful a pollutant is to living organisms
Persistence
How long a pollutant remains in its original form
Persistent
Does not break down
EX. DDT -> remains toxic
Non perisistent
Breaks down into less toxic or non toxic forms
EX: Hydrogen peroxide
Concentration
Amount of pollutant per volume (PPM, PPB)
Proactive stance
Prevents release of a pollutant.
Less expensive
Reactive stance
Cleanup after the release of a pollutant.
More expensive
Thermosphere
Thickest layer, 300 miles above surface, auroras occur here
Mesosphere
under thermosphere
Stratosphere
Ozone layer, O3
Troposphere
We live here
Weather, air we breathe, air pollution occurs here
Primary pollutants
Released directly into the atmosphere
Secondary pollutants
Form from primary pollutants when they react with something in the atmosphere.
EX: SO2 combines with H2O to become H2SO4
Particulate matter
Primary pollutant
Comes from combustion of fossil fuels, industry, construction
Causes respiratory problems, climate change: global COOLING
Carbon Monoxide
Primary pollutant
Combustion of fossil fuels
Prevents delivery of O2 to blood and tissues
Carbon dioxide
Primary pollutant
Combustion of fossil fuels
Volcanic eruptions
Wildfires
Contributes to greenhouse effect and global climate change
Sulfur dioxide
Primary pollutant
Combustion of fossil fuels (coal+diesel release mercury)
Smelting
Volcanic eruptions
Toxic to plants and animals
Irritates respiratory system
Component of acid rain HNO3
Photochemical smog tropospheric (ground level) 03
Volatile organic compounds
Primary pollutant
Combustion of fossil fuels
Gas fumes, glues, paints, solvents
Toxic, can be carcinogenic
Prime agents of tropospheric/ground level O3 and photochemical smog
Heavy metals
Primary pollutant
Combustion of fossil fuels (coal)
Smelting
Industry
Damage to brain, kidney , and lungs
Sensory impairment, disturbed sensation and lack of coordination
Industrial smog (grey air fog)
Smoke and fog, smoke pollution
Sulfur oxides SOx and PM
Often occurs in winter months when heating fuel combustion is high
Photochemical smog (brown air smog)
Several pollutants (mainly from auto exhaust) react with sunlight
Nitrogen oxides and volatile compounds react with heat and sunlight to produce a variety of pollutants
Nitric acid, ozone, PANs, formaldehyde
Decreased visibility, harms human health by irritating the respiratory system, skin and eyes, damages vegetation
Forms in urban areas
Normal conditions
Warmer air at surface, pollutants rise and dissipate
When it rises, it takes the pollutants with it and disperses it
Thermal/temperature inversion
The normal temperature gradient is altered as the air at the surface is cooler
Cool air sinks and holds air pollution at the surface. A thermal inversion will trap pollution close to the ground
Los Angeles
Prone to inversions and smog
Surrounded by mountains, so cold air gets stuck
Poor air quality
High automobile density and sunlight
Tropospheric ozone
Harmful at the surface
Good up high, bad nearby
Destroys chlorophyll in plants and makes them more susceptible to disease, harmful to lung tissue, respiratory
Reaction that creates tropospheric ozone: car echause + sunlight
Wet deposition
Sulfuric and nitric acids in precipitation
Dry deposition
Sulfuric and nitric acid containing particles that settle out of air (PM)
Normal rainfall
Slightly acidic due to CO2 dissolving in H2O to form dilute carbonic acid
5.6 PH, anything below is acid rain
Acid deposition
Acidification of lakes and streams
Acidification of soils
Acid frees aluminum from soil
Aluminum is toxic to plants
Buffering of lakes and soils
Soils with a parent material of limestone and marble can help neutralize acid rain
Ozone depletion in the stratosphere
Protective O3 is in the lower stratosphere
The ozone layer is important to evolution and survival
Ozone depleting compounds
ODCs
refrigerators, air conditioners, fire extinguishers, aerosols, ETC
Location of Ozone thinning
Most thinning occurs in October, its Spring for the southern hemisphere
Occurs due to polar stratospheric clouds
Effects of O3 depletion
More UV rays
Decreased crop yield
Kills phytoplankton
Skin cancer, cataracts
Montreal Protocol
Banned CFCs
CFC substiutes
HFCs
Ozone is healing
Negative feedback
Causes a system to change in the opposite direction, helps to maintain homeostasis/equilibrium
Desirable
Positive feedback
Causes a system to change further in the same direction, tends to allow a system to run out of control
Atmosphere as a greenhouse
Earth’s atmosphere Acts as a greenhouse
Sunlight passes through as shortwave
Energy is absorbed at the surface and reradiates as long wave rays (heat)
Long wave radiation is captured and held by greenhouse gasses
Global temperatures increase in the lower atmosphere
CO2
Combustion of fossil fuels
Deforestation
Methane CH4
Fossil fuels burnings, Livestock (manure)
Anaerobic decomposition- wetlands, rice paddies and landfills, release from permafrost
Nitrous oxide N2O
Combustion of fossil fuels, biomass, fertilizer
Microbes break down fertilizer and add N2O to the atmosphere
CFCs
Reaction with O3
Cycle
Long residence time in the atmosphere (15-200 years)
cl as a catalyst
Ozone depletion
Old aerosol sprays, refrigerators, air conditioners
Keeling curve (Northern hemisphere)
Seasonal photosynthesis causes fluctuations
Rising sea levels
Thermal expansion: More volume
Melting of ice sheets (ice on land): Melts+runs off
