Chapter 16 Envi Sci
High concentration of nitrogen dioxide causes
damage to plant leaves. It also causes respiratory problems.
air pollutants movement through atmosphere
natural/ human generated sources→ wind transport and chemical reactions→ haze/ deposition→biological effects on natural environment
nations with lowest air pollution
new zealand, Brunei Darussalam, Sweden, Australia, Canada
tropospheric ozone sources
oil and gas, biogenic sources (forest fire), vehicles, planes, non-road engines (lawn mower)
Smoke
particulates formed during combustion of organic matter. For example, garbage, burning of fossil fuels, smoke from burning of oil.
Over ___% of world's population lives in places where air pollution is above World Health Organization (WHO) guidelines.
90%
What are overall effects of air pollution?
-Acid rain is most common result of air pollution. -Acidification causes damage to both plants and animals. -Ozone depletion is another important effect of atmospheric pollution. -Photochemical smog is another effect of air pollution. -Respiratory diseases are another effect of air pollution.
What are effects of photochemical smog?
-Causes eye irritation -Headache, chest pain, cough, difficulty in breathing -Damage to the plant life -Corrosion of stones and metals -It also leads to cracking in rubber
air pollution deaths in 2012
1) china 2) India 3) russia 4)indonesia
What are sources of CO2, a greenhouse gas?
1) electricity generation 2)transportation 3) industry
By the ___ in USA , the environmental movement began to emerge. This movement sought to stem the tide of pollutants flowing into the planet's ecosystems.
1960s
About ____% of solar radiation is absorbed in atmosphere, ___% is reflected and ___% absorbed by Earth's surface.
23%, 29%, 48%
VOCs sources
26% vehicles, 28% solvent use, 18% non-road equipment
nitrogen oxide sources
35% vehicles, 23% non-road equipment
lead sources
42% non-road equipment, 41% industrial processes
"We still have _____ deaths in Europe [per year] and this is totally unacceptable."
500,000
carbon monoxide sources
59% vehicles, 25% non-road equipment
sulfur dioxide sources
73% electricity generation
In 1905, the term "smog" identified and defined:
A mixture of smoke (sm) and fog (og).
___ is highly polluted but little measured.
Africa
How is air quality measured?
Air Quality Index (AQI)
least polluted places in USA
Albany NY, Honolulu, Casper WY, Bismarck ND
How is ozone depleted?
CFCs in atmosphere absorbs ultraviolet rays and forms chlorine free radical. These chlorine free radicals formed are continuously used to breakdown the ozone.
_____ is one of the toxic pollutant
Carbon monoxide
Out of this movement came events like Earth Day, and legislative victories like the_________ and ________.
Clean Air Act (1970), the Clean Water Act (1972
Since the_____ and ______, air pollution has decreased markedly.
Clean Air Act of 1970, the identification of these pollutants
most polluted places in usa
Fairbanks Alaska, Visalia-porterville-hanford CA, Bakers field CA, LA CA
Hydrocarbons (VOCs) are composed of hydrogen and carbon and are caused by__
Incomplete combustion of fossil fuels used in automobiles forms hydrocarbons.
____ has 20 of 33 most polluted cities in the world.
India
ground level ozone formation
Nitrogen Oxides + VOCS=Ozone (pollutants "bake" together in direct sunlight forming ozone)
what is PM 2.5?
PM 2.5 is the concentration of microscopic particles less than 2.5 microns in diameter.
what is PM 10
PM10 refers to the concentration of particles less than 10 microns in diameter.
Formation of photochemical smog
Primary pollutants, like oxides of nitrogen and VOCs, interact due to sunlight to produce a hazardous chums (secondary pollutants) like Add to peroxyacetyl nitrates (PAN) and ground-level ozone.
Hydrocarbons (VOCs) cause
They are carcinogenic. They cause ageing in plants, shedding of flowers and leaves etc.
How is this ozone formed?
When oxygen (O2) absorbs ultraviolet rays, it breaks into oxygen atoms. O2 molecules combine with O atom to form O3 (ozone).
Stratosphere
above troposphere where protective layer of ozone is present.
Technically, greenhouse gases are not classified as _____
air pollutants.
Sulfurous smog
also called "London smog," results from high concentration of sulfur oxides in air and caused by use of sulfur-bearing fossil fuels, i.e., coal.
Air Quality Index (AQI)
an index used by government agencies to communicate to public the current status of air quality and how polluted it may become. Public health risks increase as the AQI rises. Different countries have their own air quality indices.
Fumes
are another non-viable particulate pollutants that are formed due to condensation of vapors during distillation, boiling etc.
Dust
are particles that are formed due to various sources such as crushing or grinding of solid particles. Sand, saw dust, fly ash, etc. are also important source of particulate matter.
Mists
are small water droplets that decreases the visibility in the atmosphere. For example, Mist from herbicide and insecticides.
greenhouse gases
carbon dioxide, methane, nitrous oxide, water vapor, carbon monoxide, CFCs, Sulphur Dioxide, and ozone in the atmosphere which are involved in the greenhouse effect.
major primary pollutants and their sources
carbon monoxide (49.1%), sulfur oxides (16.4%), nitrogen oxides (14.8%), VOCs (13.6%), particulates (6%) transportation (46.2%), stationary source fuel combustion (27.3%), Industrial processes (15%)
air pollution affects on health
carbon monoxide: head fatigue lead: nerve damage VOCs: cancer, nausea, skin irritation particulate matter: respitory disease
The main pollutant behind the ozone depletion is _____ known as ____.
chlorofluorocarbon (CFCs), Freon (CFCs are used in refrigerators)
Oxides of Sulfur are formed when
fossil fuels are burnt. Burning of fossil fuels form Sulfur dioxide.
Carbon monoxide has a strong affinity to bind with ____.
hemoglobin, This reduces the amount of oxygen that bind with the hemoglobin. This forms carboxyhemoglobin which causes reduce availability of oxygen to tissues.
Photochemical smog
is produced when sunlight reacts with nitrogen oxides (NOx) and at least one volatile organic compound (VOC) in the atmosphere. Nitrogen oxides come from car exhaust, coal power plants, and factory emissions. When sunlight hits these chemicals, they form airborne particles and ground-level ozone—or smog.
Thermosphere
layer where sun's rays are first absorbed, that is, X-rays, UV-rays etc.
Mesosphere
layer where temperature is low and air is thin to breathe.
Oxides of Nitrogen are formed when
lightning strikes the oxygen at higher altitude. During burning of fossil fuels at high temperature, oxygen and nitrogen combines to form nitrogen dioxide and nitric oxide. Nitric oxide than reacts further with oxygen to form nitrogen dioxide. NO formed also reacts with ozone to form nitrogen dioxide and oxygen.
Troposphere
lowest region where living organisms inhabit & pollutants first collect.
Particulate pollutants include ____ or _____.
minute solid particles or liquid droplets suspended in air
What are four major sources of air pollution?
mobile sources (cars, buses, planes, trucks, and trains), stationary sources (power plants, oil refineries, industrial facilities, and factories), area sources (agricultural areas, cities, and wood-burning fireplaces), natural sources (wind-blown dust, wildfires, and volcanos)
Sulfur dioxide is harmful for
plants and animals and causes respiratory disorders. It also causes irritation in eyes such as tears and redness. In plants, it causes flower buds to fall from the plant. The oxides of sulfur are potential agents that causes acid rain.
secondary pollutants
pollutants that are formed by the combination of primary pollutants in the atmosphere. (ozone, sulfate, nitrate)
Carbon Dioxide is added to the atmosphere by
respiration, burning of fossil fuels, and decomposition of limestone.
nartiopns with highest air pollution
saudi arabia, qatar, egypt, bangladesh
The source of particulate pollutants can be ______
smoke particles from fires, vehicle emissions, ash, dust particles etc. Bacteria, viruses, molds, algae also qualify as a particulate pollutant.
Overall: Air pollutants can be ______, ______ and _____ or any ______
solid, liquid, certain gases, particulate matter
air pollution is the worst in ____
south and east Asia, where most of humanity lives, with traffic, dirty industry and the open burning of waste delivering a triple whammy
The ______ contains a layer of ozone that protects the Earth from harmful ultraviolet rays
stratosphere
six major air pollutants
sulfur dioxide (SO2) nitrogen oxides (NOx) ozone (O3) particulate matter (small suspended particles of varying sizes) carbon monoxide (CO) volatile organic compounds (VOCs)
primary pollutants
sulfur dioxide, carbon monoxide, nitrous oxide, carbon dioxide, NO2
There at least two distinct types of smog
sulfurous smog and photochemical smog.
In the modern world, fossil fuel (oil, coal, natural gas) combustion is the biggest contributor to air pollution. The leading sources today include _____, ______ , _______, ______, ______, _____
vehicular traffic, factory & industry productions, mining operations, agriculture, domestic/commercial, and electric-generating power plants.
VOCs
volatile organic compounds
How does the AQI work?
works like a thermometer that runs from 0 to 500 degrees. The AQI is a way of showing changes in the amount of pollution in the air.