TOPIC 6 Flashcards
Photochemical reaction (in the context of air pollution)
-Reactions sped up by the solar energy of UV radiation
-with air pollution, create SECONDARY POLLUTANTS from the PRIMARY POLLUTANTS formed by the combustion of fossil fuels
greenhouse gases
DIFFERENT from atmosphere composition
mainly
-water vapour
-carbon dioxide
-methane
wet deposition (3 points)
-when acid pollutants are dissolved in precipitation
-can fall at great distance from sources
-example of trans-frontier pollution; crosses itnernational boundaries
How do ODSs (ozone-depleting substances) function?
Halogen atoms (e.g., chlorine) INCREASE destruction of ozone in a REPETITIVE cycle, allowing more UV radiation to reach the Earth
role of the albedo effect from clouds in regulating global average temperature
-ability of surface to reflect sunlight
-light coloured reflect a lot (high albedo); dark surfaces ABSORB a lot (low albedo)
-negative feedback system; clouds act as barrier, reflecting radiation back into space and reducing amount of heat absorbed by ground, which reduces the amount of sunlight
List secondary pollutants of acid deposition and how they’re formed
-sulphuric acid (H2SO4)
-nitric acid (HNO3)
both are formed from primary pollutants by REACTION with WATER
regions causing acid deposition
-W Europe
-US industrial belt
-China
-India
Stratospheric ozone formation (2 points)
-UV breaks apart O2 molecules and these REACT with O2 to form O3
-the O3 molecules are also broken apart by UV radiation but REFORM in a DYNAMIC EQUILIBRIUM
Greenhouse effect (define)
A natural phenomenon of the atmosphere, trapping SOLAR RADIATION in the TROPOSPHERE and keeping the Earth at a livable temperature for living systems
role of the greenhouse effect in regulating temperature on Earth.
-greenhouse effect: natural warming of earth from when atmosphereic gases trap heat from sun that would otherwise escape
-keeps earth at a livable temperature
effects of UV radiation o nhumans
-damages living tissues
-increases incidence of cataracts
-mutation during cell division
-skin cancer
impact of tropospheric ozone on the economy
-increased cost of healthcare
-loss of crops damaged by tropospheric ozone
-loss of time labourors are able to work due to extreme heat caused by tropospheric ozone
-cost of clean-up
-loss of tourism
Dry deposition (2)
-Ash and dry particles of acids
-occurs close to emission source
-causes damage to buildings and structures
Causes of acid deposition
-fossil fuels (coal, oil, gas) –> burned –> become sulfur dioxide and nitrogen oxide –> released into atmosphere, absorbed by moisture and become weak sulfuric and nitric acids
fluctuation in ozone concentration
-SEASONAL
-springtime: marked reduction in ozone over Antarctica
-summer developing: ozone recovers
-reason: in winter, air over aAntarctica becomes cut off from the rest of the world
Smog (definition + examples of causes)
A complex mixture of primary and secondary pollutants of which TROPOSHPERIC OZONE is the main pollutant.
caused by:
-burning of fossil fuels (transportation and industry)
-deforestation and burning (in North India and Indonesia)
4 factors that can influence frequency and severity of smog and HOW
-topography
-climate
-population density
-fossil fuel use
HOW
ODS meaning
ozone depleting substance
Halogenated gases
Compounds which contain atoms from Group VII of the periodic table (e.g., chlorine, fluorine, bromine)
Direct effects of acid deposition (list 2)
-Intolerance of aquatic organisms to CHANGES in pH
-coniferous forests do not shed leaves so stays in the system, and have REDUCED IMMUNITY to pests and diseases
What is the concetration of oxygen gas in the atmosphere?
~20%
effects of UV radiation on biological productivity (list 1)
Damages photosynthetic organisms (especially phytoplankton, which form the basis of aquatic food webs)
Tropospheric ozone
A secondary pollutant formed when oxygen MOLECULES react with oxygen ATOMS that are released from NOx in the presence of SUNLIGHT
-the evil ozone
Factors that determine frequency and severity of smog (list of 4)
-local topography
-climate
-population density
-fossil fuel use
What is an indirect effect of acid deposition? (list 2)
-Increases solubility of metals such as aluminium, which causes white froth to form in fish gills, leading to suffocation.
-Leaching of plant nutrients, so soil has decreased fertility
What is the nitrogen gas concentration in the atmosphere?
~79%
Troposphere
The first layer of the atmosphere where weather occurs (0-10km)
Stratosphere
Second layer of the atmosphere (above troposphere) where ‘good’ ozone exists, proctecting us from the sun’s UV radiation
Albedo
The reflectiveness of a surface; white is high albedo and refelcts more solar radiation
What were the CO2 ppm in the 80s vs 2016?
was 350 ppm in the late 80s, in 2016 reached 400 ppm (0.04%)
regions impacted by acid deposition
acid rain:
downwind of major industrial regions such as:
-Scandinavia (downwind W. Europe)
-NE USA, E Canada (downwind from US industrial belt)
List primary pollutants from combustion of fossil fuels (list 6)
-Carbon monoxide (CO)
-carbon dioxide (CO2)
-black carbon/soot (C)
-unburned hydrocarbons
-oxides of nitrogen (NOx)
-oxides of sulphur (usually SO2)
What are ozone-depleting substances and what are they used in?
Halogenated organic gases (.e.g, chlorofluorocarbons) are used in
-aerosols
-gas-blown plastics
-pesticides
-flame retardants
-refrigerants
What gases make up the atmosphere? (list 6)
-Nitrogen
-Oxygen
-Carbon Dioxide
-Argon
-Water vapour
-Trace gases
Thermal inversions (3 points + example location)
-Occur because a lack of AIR MOVEMENT when a layer of DENSE COOL AIR is trapped BENEATH a layer of LESS DENSE, WARM AIR
-causes the CONCENTRATION of air pollutants to BUILD UP near the ground instead of being DISSIPATED by ‘normal’ air movements
-air pollutant concentration can build up to harmful/lethal levels –> toxic and carcinogenic chemicals are produced
The atmosphere
A dynamic system that has undergone changes throughout geological time
Effects of tropospheric ozone (list 4)
-plant damage (crops, forests)
-irritates eyes
-respiratory illnesses
-damage to fabric and rubber materials
reasons for illegal trade of ODSs
-substitutes are often costlier than CFCs
-updating equipment to enable use of alt chemicals is expensive
-penalties for smuggling ODSs in many countries are LOW
list of primary pollutants
-carbon monoxide
-carbon dioxide
-black carbon
-unburned hydrocrabons
-oxides of nitrogen
-oxides of sulfur
black carbon
fine particulate matter emitted from incomplete combustion
unburned hydrocarbons
volatile organic compounds (VOCs) released during combustion
oxides of nitrogen
NOx
-key contributors to air pollution
-cause RESPIRATORY issues
-contribtue to the formation of smog
oxides of sulfur
-SOx
-released during fossil fuel combustion
-leading to acid rain
-respiratory problems
secondary pollutants
-tropospheric ozone
-nitric acid and nitrate particles created by NOx –> contribute to acid rain
-
economic losses related to smog
-healthcare costs
-reduction in productivity
-loss of work days
-environmental damage
-decreased property values
healthcare costs related to smog
-poor air quality in urban areas -> increase in respiratory and cardiovascular dieases
-higher healthcare costs for individuals, businesses, governments
-treatment of pollution-related illneses, including hospitalisations, meds, long-term care
-can put a strain on healthcare systems and result in substantial economic burdens
reduction in productivity related to smog
-can have detrimental effect on worker productivity
-exposure to polluted air can lead to respiratory issues, allergies, fatigue –> can impair work performance
-can translate into economic losses for businesses and the overall economy
loss of workdays related to smog
-severe air pollution triggers HEALTH WARNING –> people stay indoors or limit outdoor activities
-results in missed workdays or reduced working hours, impacting business and individuals’ incomes
-when pollution-related health issues force workers to take sick leave -> affects productivity
