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Aerosol network
Guoxun TianCS 790GFall 2010
Overview
Introduction Why is it important to study?
Harms from air pollution Aerosol transport Why ozone? And why California
Ozone transport and Previous Work Conclusion Questions
Introduction
Definition of aerosol
Technically, an aerosol is a suspension of fine solid particles or liquid droplets in a gas. Examples are smoke, oceanic haze, air pollution, smog and CS gas (C10H5ClN2)Fig. 1 Aerosol-contamination in northeastern India and Bangladesh
Introduction
Beijing, OCT .08 2010
What do aerosol looks like?
Pictures of Aerosol Particles from Biomass Burning
Introduction
Chakrabarty, R. K., H. Moosmüller, M. A. Garro, W. P. Arnott, J. W. Walker, R. A. Susott, R. E. Babbitt, C. E. Wold, E. N. Lincoln, and W. M. Hao (2006). “Emissions from the Laboratory Combustion of Wildland Fuels: Particle Morphology and Size.” J. Geophys. Res. 111, doi:10.1029/2005jd006659 (in press).
Source of aerosol There are many pollutants: Ozone (O3), Respirable Particulate
Matter (PM10) , Fine Particulate Matter (PM2.5), Carbon Monoxide (CO), Nitrogen Dioxide (NO2), Sulfur Dioxide (SO2), Sulfur Dioxide (SO2), Sulfates, Hydrogen Sulfide …….
There are many source of above pollutants and the interaction between them are complex.
Introduction
7
Satellite Image of Wildfire Smoke
Smoke from Southern California wildfires (26-Oct.-2003)
Introduction: Source of aerosol
Burning Brazilian Forest near Ji Parana: Pyrocumulus
Courtesy Michael Welling, SMOCC (Sept 25, 2002)
Introduction: Source of aerosol
Source of aerosolIn our daily
life
Introduction
Source of aerosol Source of PM10 and PM2.5: PM10: Dust, Windblown Dust (Agriculture)
and Construction (Fireplaces) Also formed from other pollutants (acid rain, NOx, SOx, organics). Incomplete combustion of any fuel. PM2.5: Fuel Combustion in Motor Vehicles, Equipment and Industrial Sources, Residential and Agricultural Burning. Also formed from reaction of other pollutants (acid rain, NOx, SOx, organics).
Introduction
Source of aerosolIn our daily
life
Introduction
Why is it important to studyIntroduction
California's air pollution control program is one of the most effective in the world. Coordinated state, regional, and local efforts have steadily improved air quality. As a result, the air is the cleanest in years. For example, in the Los Angeles area - the most seriously polluted region in the nation - the highest levels of pollution have dropped by 25 percent since 1980. Annual exposure to smog has decreased by 50 percent.
But Pollution is Still a Problem. Despite these improvements, California continues to face the nation's greatest air quality challenge. The state's sunny climate, pollution-trapping mountains and valleys, along with the activities of 32 million Californians all contribute to the problem. Every year more than 90 percent of all Californians breathe unhealthy, polluted air. This harms our health, the economy and climate.
Why is it important to study- Climate changing (global warming, ice melting, etc)- Health effect (e.g. inhaled atmospheric particles were found in the
lungs, liver, spleen, kidneys, heart, brain etc.)- Economy (Every year, Californians lose billions of dollars due to air
pollution. The cost of health-related problems, plus damage to crops, forests, and wild vegetation, all add up to a big drain on California's economy. Air pollution is something we can't afford.
1.25
1.20
1.15
1.10
1.05
1.00
Mort
ali
ty-R
ate
Rati
o
30252015Fine Particles, µg/m3
PT
W
LH
S
Estimated Adjusted Mortality-Rate Ratiosand Pollution Levels in the Six Cities (USA).
Introduction
Aerosol transportation Schematic diagram
Black Carbon Emissions
Emissions from-fuel combustion (fossil fuels and biofuels) -open biomass burning (forest fires, savanna burning and outdoor cooking)
The uncertainty is about ±100% or more.Ton/yr-1 from a study by Bond et al.
DOMESTICCOAL BURNING
BIOMASSBURNING
• TOTAL BIOMASS BURNINGfrom 4000 to 10400 Tg a-1
• Total soot production from 60 to 100 Tg a-1
http://en.wikipedia.org/wiki/File:Map_prevailing_winds_on_earth.png
Westerlies and Trade winds
2
3
Global Aerosol Transport
R. Husar et al.(1998)
April 1998 event
http://en.wikipedia.org/wiki/File:Chinadustmovie.gif
http://en.wikipedia.org/wiki/File:Dust_movie.gif
Transport of East Asian Dust across the pacific
What is Ozone?
Ozone, an important ingredient of smog, is a highly reactive and unstable gas capable of damaging the linings of the respiratory tract. This pollutant forms in the atmosphere through complex reactions between chemicals directly emitted from vehicles, industrial plants, and many other sources. Key pollutants involved in ozone formation are hydrocarbon and nitrogen oxide gases.
Why ozone?
Ozone is a colorless gas at normal atmospheric concentrations that is a natural part of the environment. In the upper atmosphere, ozone protects the earth from exposure to harmful ultraviolet rays. However, ozone can be formed in the lower atmosphere by natural processes or by man-made pollutants.
Ozone is created by a chemical reaction:
Where Does Ozone Come From?
O3+ =
VOC + NOx + Heat + Sunlight = Ozone
VOC (Volatile Organic Compounds) and Nox (Nitrogen Oxides) come from motor vehicles, power plants, industrial facilities, and other sources.
Why ozone?
Standard of Ozone
Why is Ozone Bad to Breathe?
The average adult breathes enough air to fill over 3,000 balloons each day. Children breathe even more!
Ozone can irritate lungs and airways, and cause inflammation much like a sunburn on your lungs.
Ozone can aggravate respiratory illnesses like asthma.
10 to 20% of summertime respiratory-related hospital visits in the Northeast are associated with ozone pollution.
Children and people with chronic lung diseases are particularly at risk.
Why California
There are currently 4 states in the West with areas that do not comply with the 8-hour standard, including California, Nevada, Arizona, and Colorado. The graph contains a map showing areas classified as non-attainment in the West. And California was the worst.
Ozone Transport
Long-range transport, is caused by a number of factors. The main factor found by the East being the flow and direction of wind. In a paper prepared by the System Applications International, Inc. dealing with the long-range transport of ozone, it was found that “moderate to high wind speeds were classified as having a moderate to high potential for a contribution from transport” (Douglas and Hudischewskyj, 1997).
Ozone Transport
Long-range transport of ozone and precursors has become a question in the West. Unlike the East, Western ozone was typically thought to be isolated to a local area.
Recent modeling for the Denver Early Action Compact indicated transported ozone significantly impacted the final ozone concentration recorded in the Denver region (Regional Air Quality Council, 2004).
Ozone Transport July 1 - 2
Robert A. Baxter, CCMT&B Systems
Clark County Air Quality Forum – 03/14/06
Studying Ozone transport network is important
Hope I can find something new.
Conclusion
Thanks
Question