Chapter 7 Managing the Atmosphere Flashcards
cause and impact of air pollution - acid deposition, photochemical smog and ozone depletion
Acid Deposition
- Acid deposition is a mix of air pollutants that deposit from the atmosphere as acid wet deposition (with a PH <5.6) or acidic dry deposition
** Two types of acid deposition**
1. Wet deposition (snow, rain, hail and fog
2. Dry deposition (dust and gases)
Formation of Acid deposition
- fossil fuels contain sulfur compounds. burning of fossil fule releases sulfur dioxide gases
- sulfur dioxide gase reacts with water and oxygen to form sulfuric acid
- nitrogen monoxide gases reacts with oxygen and water in the atmospher to form nitric acid.
Impact of acid deposition on acquatic environ., veg and crops, stone and brick buildings
- effects on fish gills and fish populations
- defoliation and reducted crop yield
- chemical weathering ( changes the molecular structure of rocks and soil. For instance, carbon dioxide from the air or soil sometimes combines with water in a process called carbonation. This produces a weak acid, called carbonic acid, that can dissolve rock.
Photochemical Smog
Mixture of air pollutants and and particulates, including ground
level ozone, that is formed when oxides of nitrogen and volatile organic compounds (VOCs) react in the presence of sunlight
Impacts of photochemical smog
* eye and respiratory irritation
* decreased crop yields
* deterioration of plastics and rubber
Managing Air Pollution
- Introduction of harmful substances into the atmosphere, which can have detrimental effects on human health and the environment.
- Common air pollutants include particulate matter (PM), ground-level ozone (smog), sulfur dioxide (SO2), nitrogen oxides (NOx), and volatile organic compounds (VOCs)- Air pollution can lead to respiratory problems, cardiovascular diseases, and even premature death.
- Vulnerable populations, such as children and the elderly, are more susceptible to these health risks.
Strategies for managing air pollution
- reduce use of fossil fuels
- reduce emission of sulfur dioxide
- safe usage, storage and disposal of household products (VOCs)
- restrict use of vehicles in urban areas
- legistlations (local, national and international legislation,
- penalities for polluters.
Air Quality Monitoring and Regulation:
. - Governments and environmental agencies monitor air quality using air quality indices (AQI).
- Regulations and policies, such as emission standards and vehicle emissions testing, aim to reduce air pollution.
Ozone depletion:
chlorofluorocarbons (CFCs) from aerosols and
refrigerants are unreactive compounds and are
not broken down in the troposphere
* CFCs move into the stratosphere and break down
in the presence of ultraviolet light to release a
chlorine atom
* rapid reactions between chlorine atoms and
ozone breaks down ozone (O3) to oxygen (O2),
causing ozone depletion
* chlorine atoms remain in the stratosphere and
can continue to destroy ozone
Measure Ozone concentration
Using Dobson Unit
Ozone Hole
an area where the
average concentration of ozone is below 100 Dobson Units
Impact of increased UV Radition due to Ozone depletion
- human health (cataracts, skin cancer)
- decreased crop yields
- biodiversity of terrestrial and aquatic ecosystems
- degradation of materials used in clothing and construction
)Importance of evidence to support hypothesis (e.g Ozone destruction hypthosesis - Rowland Molina
- initially the main hypothesis was not accepted
- some of the auxiliary hypotheses were not backed up by experimental evidence
- the hypothesis led to further research and data collection by other scientists, which confirmed that CFCs are ozone depleting
Case study
Causes and Impacts of a named atmospheric event and evaluate the management of the pollution event
- India’s Bhopal Cyanide Gas Leak
- Chernobyl Nuclear Disaster
- Romania’s Cyanide Spill
- Ivory Coast’s Toxic Waste Dumping
- Amazon Wildfires
