chapter 18

Options: washing away air pollution with artificial rain ?sucking it up with giant vacuum cleaners ?Shanghai has given its cops nose insert mini-filtersA study published in the British medical journal the Lancet attributed 1.2 million premature deaths in 2010 to bad air

A possible solution to China's smog:

Giant vacuum cleaners

Chapter 18air pollution

Types and behaviorUS pollution DistributionCarbon cycle and weatherOzone & acid rain casesSolutions

Types of Air PollutionGaseous pollutants

CO and CO2

SO2

NO, NO2 [NOx ]O3 and CFCs –[chlorofluorocarbons]

ParticulatesSoot, ash, & smokeDust (released from industrial processes)Not a minor component - from 35 million tons/year (mainly

combustion) to 180 million tons/year (mostly industrial)Residence times vary widely, from a few years to millions of years – related to amount in the atmosphere, so N & O hang around longest

Major Emissions

CO – carbon monoxide – vehicles, combustionNot abundant but deadlyVery short residence time – fluctuating concentration

SO2 - sulfur dioxide – from combustion of coalforms acid rain – pH << 6very short residence time (days or hours)Mostly decreasing at least in US

NOx – nitrogen oxides – “smog ozone” interacts at several levels

reacts in sunlight to form opaque NO2, + ozone (O3), acids, etcEmissions steadily increasing

VOC – volatile organic compounds – breakdown products of industrial process, plastics, petroleum, etc

CO2 - carbon dioxide - combustion, and natural like respiration, volcanic eruptionsVarying residence time and fluxesRapidly, steadily increasing

US air pollution$16 billion annual U.S. expense (direct costs) vs $40B globally

Major gas sources:Transportation: [1] CO,

[1] NOx, [1] VOC, [1] CO2

Energy: [1] SO2, CO2,NOx

Industry: VOC, SO2, CO2 Transportation ranks first

in several categories

Particulates are heavily influenced by industry, greatly reduced in recent years

US gas emissionsComparing two classes shows

complex, interesting history

Sulfur

Nitrogen

The global carbon cycleComprised of sources and

sinksCO2 and CO are emitted

and travel through this cycle

Combustion and other emissions greatly alter the proportions

Major effects: greenhouse gases, plant building, hydrocarbon formation

These gases interact with lithosphere, biosphere and hydrosphere in often complex chemistry

Other compounds have similar cycles, sources and sinks

Air Pollution and WeatherThermal InversionWarm, polluted air tends to rise, cooling as

it goes a cool air mass can have an overlying air

mass trap the rising warm pollutant-bearing air mass; this condition is made worse by an air mass with stagnant conditions

Topography, climate may amplify the problem

Pollutants are concentrated in the lower air mass and trapped, yuk!

OzoneOzone (O3) is a ‘chemically out of place

pollutant’ – good high up, bad low downIn upper atmosphere the ozone layer absorbs

harmful ultraviolet radiationChlorine and fluorine are chemically active

ions that rip O3 apart & reduce O3 concentrations

Recently, banning CFCs has returned ozone to upper atmosphere

Acid RainAn acid solution has more Hydrogen-ions (H+) – measured in pH

Several common gases combine with water and air to make acids

Acid rain is harmful to plants,

health of rivers and lakes,

and animals – also causes

increases in the build up of

heavy metals (lead, zinc,

selenium, copper, and

aluminum) leached from

rocks and soils

Chinese Smog Created By Our

Demand for Cheap Goods Comes to L.A.

Global solutions

Air Pollution regulation

strong legislation that created the EPA - Environmental Protection Agency

Regulations cover catalytic converters and high fuel economy standard for new cars

Air Quality Standards – Clean Air Act (1970)

Result: dramatic reduction in emissions, especially the most harmful categories

The end

Thanks for taking a look at the Environmental Geology slides!