Air Pollution
Mexico City Clear Day Not so clear day
Smokey Mountains
Smog – US, global Denver Houston Beijing Tokyo
Smog When air pollution hangs over urban areas and reduces visibility.
Atmosphere – the gaseous envelope surrounding the earth
Air pollution The presence of chemicals in the air in high enough quantities to cause harm
Sources of Air pollution Mobile Stationary VehiclesForest Fires Power plantsVolcanoes Man Made Natural
Primary Pollutants CO CO 2 SO 2 NO Volatile organic compounds Particulate matter – “stuff” floating in the air –Ex: soot from smoke, fine cement particles Pollutants emitted directly into the air by human activity
Secondary Air Pollutants SO 3 H 2 O 2 O 3 – ground level ozone When primary pollutants react with one another or the air to form another pollutant
Motor Vehicles Produce the most air pollution by burning gas Clean Air Act 1970 Gave the EPA the authority to regulate car emissions –Unleaded gasoline –Catalytic converters – clean exhaust – makes water
ZEV’s Zero-emissions vehicle –No tailpipe emissions –No gas emissions –No emission control system Electric cars – only true ZEV Partial ZEV’s –Hybrids –Methanol fuel cells
Temperature inversion What is it? Why is it bad?
© 2003 John Wiley and Sons Publishers Fig Two causes for the development of atmospheric inversion, which may aggravate air pollution problems. LA or Lima London
How does Temperature inversion affect Knoxville?
Donora, PA Donora Death Fog
Donora, PA October 1948 air pollution event killed at least 20 and hospitalized close to half of the town. Public outcry helped set in motion early air pollution regulations.
Alcoa??
“Pea Soup” London smog
12000 people died prematurely What do you think caused all the smog?
Factors that help reduce air pollution Precipitation (rain, snow) Sea spray Wind
Factors that increase air pollution Urban buildings Hills/mountains High temperatures
Acid rain – Precipitation that contains high concentrations of acid 3.5 – 5.0 on the pH scale (about as acidic as tomato juice) Normal is about 5.8 – 6.0 Causes acidification – a rise in the acidity of soil and water –Some nutrient are dissolved –Some toxic chemicals are released
Smokey Mountains
Acid Shock When acid snow melts and large amounts of acid rush into water. Kills many aquatic species
Forests of Vermont – dying Coal burning in Ohio Valley
What harmful effects does it cause to humans? Resperatory disease –Bronchitis –Asthma
Other ways acid rain can cause damage Can leach toxic metals in to water source Damages metals, statues, buildings etc. Water and soil pollution
What can we do? Reduce emissions Limestone in lakes –Expensive –Temporary –Kills some aquatic life Fertilizers?
Indoor Air Pollution Usually 2-5 times higher than outdoors Can be 100 times greater
As much as 18 times higher in a car On average people spend 70-98% of their time indoors or in their cars.
Sick building syndrome Bad pollution - causes dizziness, headaches, coughing, sneezing, etc. New buildings worse than old ones –B/c there is less air exchange to save energy –Chemicals from new furniture and carpet =
Most dangerous indoor air pollutants Cigarette smoke Formaldehyde (fabrics) Radioactive radon (in rocks) Fine and ultrafine particles
Other Indoor Pollutants Radon – colorless, tasteless, odorless gas –Radioactive and causes lung cancer –Found in rocks below your home –Second leading cause of lung cancer in US Asbestos – used as a heat insulator –US banned its use in the early 1970’s –Causes asbestosis
How your body helps you Nose hairs Mucus Coughing/sneezing
Too much exposure Asthma Chronic bronchitis Lung cancer Emphysema
Good News The Laws are working Between there was a 25% decrease even though –population 32% –energy consumption 42% –vehicle travel 150%
Bad News Nitrogen Oxide levels have 15% Surface ozone has increased 133 Million people still live in unhealthy areas
Improvement We need to prevent not just clean Better fuel efficiency Better regulation of small motors More CO 2 reduction
Noise Pollution Unwanted sound 12 of teens have permanent hearing loss –Caused by headphones Headphones are not regulated in the US In Europe they cannot be louder than 100dB
Light Pollution No health effect Diminishes views of the sky Wastes energy –Lights that shine into the sky Billboards Poor street lights