5.1 Nature of pollution. Pollution The contamination of air, water, or soil by substances that are...

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Transcript of 5.1 Nature of pollution. Pollution The contamination of air, water, or soil by substances that are...

5.1 Nature of pollution

PollutionThe contamination of air, water, or soil by

substances that are harmful to living organisms.

Pollution can occur naturally,(ex. through volcanic eruptions), or unnaturally (ex. the spilling of oil and disposal or industrial waste)

Two Types of Pollution: Point source pollution and non-point source

Point Source PollutionPoint source: Pollution that can be traced

back to a single origin or source (ex. sewage treatment plant discharge).

Point source pollution has a localized impact is easier to manage.

Can be challenging because it is more scattered and can be very numerous

Non-Point Source PollutionNon-point source: Pollution which cannot

be traced back to a single origin or source (ex. storm water runoff, water runoff from urban areas and failed septic systems).

More difficult to identify and manage Hard to assign responsibility

Point source or non-point source?

Sources of PollutionFossil fuels - release greenhouse gases, can

contribute to respiratory problems and acid rainDomestic waste - food waste, sewage, rubbish

(glass, plastics, paper, wood, metals) Industrial waste - heavy metals, heat (in air

and/or water), acidsAgricultural waste - fertilizers, animal waste,

and pesticides contaminate water sources

Non-point source pollution

Sources of PollutionCombustion of Fossil FuelsDomestic Industrial WasteAgriculture Systems

The Era of Fossil FuelsFossil fuels: petroleum, natural gas and coalCurrently 90% of current US energy from fossil

fuelsExpected oil production peak:2020-2030Consumption of energy currently increasing Projected world oil production will be exhausted by

2100Produces significant and diverse pollution

problemsGreenhouse gasesGaseous sulfur and nitrogen oxidesLand-based disturbances

What is crude oil?Crude oil is a liquid mixture of thousands of

organic chemicals found underground. Result of decaying organic matter over

thousands of years (fossil fuel)Found all over the world and varies

tremendously in its density, sulfur and metals content

Oil Refinery and the BP oil rig

The Refinery

World oil reserves

CoalCoal provides 25% of world’s

commercial energy; 22% of U.S. energy

Advantages:Worlds most abundant fossil

fuelCheap

Disadvantages: Dangerous to mine,Harms land, water and airCauses smog, acid rain and

global warming

World Coal Reserves

Health impacts131 million

Americans live in areas with smog pollution

Over 45,000 lives are cut short by air pollution

It is estimated that every year 60,000 children may be born at significantly increased risk of neurological defects due to mothers eating mercury contaminated fish.

Mercury Contamination

Oil Spills31,000 gallons of spilled oil into waterways

each dayBetween 1973 and 1993 there were

200,000 oil spills in the U.S. waters spilling more than 230 million gallons of oil

Land DestructionMountaintop removal in west Virginia

(for coal)Tens of thousands of coal bed

methane wells in Powder river basin in Wyoming.

Global WarmingOnly 4% of world population produces 25% of

the carbon dioxide pollutionProjected that the Earth’s surface

temperature will increase between 2.5 and 10.4 degrees F by 2100 if no major efforts are taken to reduce carbon emissions