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Home , Global distillation

ANTHROPOGENIC ACTIVITY THAT AFFECTS THE ATMOSPHERE

§ anthropogenic (human) activity: § deforestation § § releasing (including green house gases & burning of fossil fuels) § production of

1/28/16 THE ATMOSPHERE 2 ATMOSPHERIC CIRCULATION

§ Global Distillation Effect § chemicals enter atmosphere in warm regions à move to areas at higher, cooler latitude à deposited on surface § e.g. Yukon (northwestern Canada) & other pristine artic regions contain toxic compounds § find evidence in food chain à biomagnification (PCBs) § e.g. Asia à East to Pacific Ocean § 1998 Chinese dust storm: toxic metals from ore smelters à U.S.A

1/28/16 THE ATMOSPHERE 3 ATMOSPHERIC POLLUTION

§ – various chemicals (gases, liquids, or solids) present in atmosphere in high enough levels to harm humans, other organisms, or materials

§ primary air pollutants – harmful pollutants that enter directly into atmosphere due to either human or natural processes

§ secondary air pollutants – harmful chemicals that form in atmosphere when P.A.P react chemically w/ one another or w/ natural components of atmosphere

1/28/16 THE ATMOSPHERE 4 EFFECTS OF ATMOSPHERIC POLLUTION

• reduces visibility, attacks & corrodes materials, harm respiratory tracts, worsen existing medical conditions, reduce productivity of crop plants, acid deposition, global warming, stratospheric depletion

• photochemical – brownish orange formed by chemical reactions involving sunlight, nitrogen oxides, & hydrocarbons

1/28/16 THE ATMOSPHERE 5 AIR POLLUTANTS

• 7 most important classes (from regulatory perspective) • particulate matter • nitrogen oxides • sulfur oxides *sulfur trioxides & sulfuric acid S.A.P • carbon oxides • hydrocarbons • ozone *S.A.P • air toxics

1/28/16 THE ATMOSPHERE 6 AIR POLLUTANTS

• particulate matter – dust & mist (e.g. , lead, asbestos, sea salt, sulfuric acid droplets) • some have toxic or carcinogenic effects • corrode metals, erode buildings & sculptures, soil cloth • can bind w/ other particles • eventually settle out • lead à settle in ground or water • can scatter & absorb sunlight reducing visibility • varies season, location, etc

1/28/16 THE ATMOSPHERE 7 AIR POLLUTANTS

• nitrogen oxides - chemical interactions btwn N & O when source of energy (e.g. fuel combustion) produces high temperatures • inhibit plant growth, aggravate asthma, photochemical smog, acid deposition

• sulfur oxides - chemical interactions btwn S & O • acid deposition à corrode metals, damage stone, damage plants, & irritate respiratory tracts

1/28/16 THE ATMOSPHERE 8 AIR POLLUTANTS

• carbon oxides • CO – poisonous; reduces blood’s ability to oxygen

• CO2 – greenhouse gas

• hydrocarbons - organic compounds containing C

& H (e.g. CH4 – methane; natural gas) • no effect, injure respiratory tract, cancer, photochemical smog, greenhouse gas

1/28/16 THE ATMOSPHERE 9 AIR POLLUTANTS

• ozone (O3) – • beneficial in stratosphere

• CFCs () react w/ it à O2 • in troposphere à photochemical smog, reduces air visibility, health problems, reduces plant vigor, lowers crop yields, global warming

• air toxics (hazardous air pollutants (HAPs) – Cl2, lead, hydrochloric acid, formaldehyde, radioactive substances, fluorides, etc.

1/28/16 THE ATMOSPHERE 10 SOURCES OF AIR POLLUTANTS

• natural • volcanoes, fires, & plants (hydrocarbons in heat)

• anthropogenic • transportation (mobile) • nitrogen oxides, carbon oxides, particulate matter, hydrocarbons • power plants (stationary) – chemical, metal, paper • particulate matter, sulfur oxides, nitrogen oxides, hydrocarbons, carbon oxides

1/28/16 THE ATMOSPHERE 11 AIR POLLUTANTS

• technology used to control air pollutants

• The Clean Air Act (CAA) • passed 1970; updated & amended 1977 & 1990 • authorized EPA to apply & enforce CAA by establishing limits on the amount of specific air pollutants permitted everywhere in U.S.

1/28/16 THE ATMOSPHERE 12 1/28/16 THE ATMOSPHERE 13 WHERE IN THE U.S. IS ACID RAIN MOST SEVERE?

1/28/16 THE ATMOSPHERE 14 WHERE IN THE U.S. IS ACID RAIN MOST SEVERE?

1/28/16 THE ATMOSPHERE 15 http://www.sourcewatch.org/ index.php/ Coal-Fired Power PlantsExisting_U.S._Coal_Plants in the U.S.

1/28/16 THE ATMOSPHERE 16 Coal-Fired Power Plants in the U.S.

1/28/16 THE ATMOSPHERE 17 SO2 EMISSIONS

• generally, bituminous coal & lignite coal have higher sulfur content than subbituminous coal (can vary by region). • bituminous coal is concentrated in eastern half of U.S • subbituminous coal can be found in west. • lignite production is concentrated in Texas, Louisiana, & North Dakota

1/28/16 THE ATMOSPHERE 18 SO2 EMISSIONS

• coal-fired electric power plants make up largest

source of national sulfur dioxide (SO2) emissions

• Cross-State Air Pollution Rule (CSAPR) called

for 53% reduction in SO2 emissions from electric power sector by 2014.

1/28/16 THE ATMOSPHERE 19 SO2 EMISSIONS: 3 MAIN STRATEGIES TO REDUCE

• use lower sulfur coal in boilers • retire plants w/out emissions controls • install emissions control equipment • e.g., primarily flue gas desulfurization (FGD) scrubbers • post-combustion exhaust passes through alkaline solution to neutralize

1/28/16 THE ATMOSPHERE 20 Coal-Fired Power Plants in the U.S.

1/28/16 THE ATMOSPHERE 21 CLASSWORK TO COMPLETE

§ Read Ch 8: Air & Air Pollution (p. 196 – 215) § Answer the following questions from the book. You can either email Ms. Manzella your answers or write them on paper & hand in (blue tray). § p. 200 # 2 § p. 205 # 1-2 § p. 209 # 1-2 § p. 211 # 1-3 § p. 215 # 4, 5, 7, 9, 10

1/28/16 THE ATMOSPHERE 22