Air: Climate and PollutionChapter 9

Outline:

• Atmosphere and Climate• Climate Change

– El Nino– Human Causes

• Climate and Pollution– Kinds of Pollution– Sources– Transport

• Effects of Air Pollution• Air Pollution Control

Climate and Air Pollution

• Over the past 20 years, developed countries have made progress in improving air quality.

• Unfortunately, air quality in the developing world has been getting worse.

Major Air Pollutants: Problems• Sulfur dioxide - acid rain, health damage,

visibility reduction• Nitrogen oxides - acid rain, eutrophication,

growth of weedy species• Carbon monoxide - inhibited respiration• Lead and mercury - neurological damage• Chlorofluorocarbons - ozone depletion• Particulate matter - lung damage, cancer• Volatile organic compounds – isoprenes,

terpenes, methane, & benzene, chloroform, etc oxidized to CO, CO2 in the atmosphere

Los Angeles

Indoor Air Pollution• Smoking - diseases

related to smoking responsible for 20% of deaths in the U.S.

• In less-developed countries, poorly ventilated heating and cooking fires represent the greatest source of indoor air pollution.

• Long range transport

• Stratospheric ozone depletion

• Montreal Protocol - 1987

Interactions Between Climate Processes and Air Pollution

Jet Streams & Jet Streaks

http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/cyc/upa/jet.rxml

http://sd.znet.com/~aringler/jet.htm

Long range transport of pollutants

Circumpolar winds transport air pollution from heavily industrialized regions to the Arctic, where high levels of smog accumulate.

Ozone Depletion

CFC Production

Production of chloroflurocarbons(CFCs)

Montreal Protocol passed in 1987

Effects of Air Pollution

• Human health• Plant pathology• Visibility reduction• Acid deposition

Ecosystem damage caused by sulfur dioxideemissions and acid rain.

Acid Precipitation, 2000

Air Pollution Control

• Early approach: “Dilution is the solution to pollution”

• Particulate removal - air filters

• Sulfur removal - scrubbers

• Nitrogen oxide reduction - catalytic converters

• Hydrocarbon controls - afterburners

Automobile Emission Control System

CLEAN AIR LEGISLATION

• Clean Air Act (1963) - First national air pollution control.

• Clean Air Act (1970) rewrote original Act.

– Identified critical pollutants.– Established ambient air quality standards.

• Primary Standards - Human health

• Secondary Standards - Materials, environment, aesthetic and comfort.

Conventional Pollutants• US Clean Air Act designated seven major

(conventional or criteria) pollutants for which maximum ambient air levels are mandated.– Sulfur Dioxide– Carbon Monoxide– Particulates– Hydrocarbons– Nitrogen Oxides– Photochemical Oxidants– Lead

Clean Air Act• Revision (1990) - Included provision for:

– Acid Rain– Urban Smog– Toxic Air Pollutants– Ozone Protection– Marketing Pollution Rights– Fugitive emissions of volatile organics– Ambient ozone, soot, and dust.– NOx emissions

• Clear Skies ( 2002) – market-based approach

Greenhouse Gases• Carbon Dioxide - Fossil-fuel burning.

• Atmospheric levels increasing steadily.

• Methane - Ruminants, Coal-mines• Absorbs more infrared than CO2.

• Chlorofluorocarbons (CFC’s) - Refrigerants• Declined in recent years

• Nitrous Oxide - Burning organic material• Sulfur Hexafluoride - Electrical insulation

International Climate Negotiations

• Kyoto Protocol– (proposed 1997 & begins 16 February 2005)

• industrialized countries are to reduce their combined emissions of six major greenhouse gases during the five-year period from 2008 to 2012 to below-1990 levels.

• For many countries, achieving the Kyoto targets will be a major change that will require new policies and new approaches.

International Climate Negotiations

• Re: Kyoto Protocol

• Green Party Co-Leaders Jeanette Fitzsimons and Rod Donald will this afternoon be visiting the US Embassy and the Australian High Commission to deliver letters calling on their governments to ratify the Kyoto Protocol on Climate Change. ()

Science and Policy in the Kyoto Protocol

Current Conditions and Future Prospects

Developed vs.Developing

Countries

CURRENT AND FUTURE CONDITIONS

• In the United States, air quality has improved dramatically in the last decade in terms of major large-volume pollutants.– Cities where pollution is largely from traffic

still have serious air quality problems.

• Major metropolitan areas of many developing countries are growing at explosive rates, and environmental quality is very poor.

Some Good News: U.S. Trends

-2002 48% -17% -51% -34% -52% -98%

Summary:• Atmosphere and Climate• Climate Change

– El Nino– Human Causes

• Climate and Pollution– Kinds of Pollution– Sources– Transport

• Effects of Air Pollution• Air Pollution Control