Air Quality and Transport Study of the Los Angeles Basin

Bo Tan

M.S Student

Department of Atmospheric sciences

University of Nevada Reno – Desert Research Institute

• CO

• NOx

• SOx

• Reactive Organic Gases (ROG)

• Total Organic gas• PM2.5

• 486.6• 96.7• 15.9• 102.7

• 218.1• 26.3

Tons per day (2010) 1987

http://www.arb.ca.gov/app/emsinv/fcemssumcat_query.php

• 9796• 889.5• 113.5

• 2429

Air Quality

• City Smog– Industrial Emission (point source)

VOC: Volatile Organic Compounds

SOx : Sulfur oxides

[Na2CO3(s)]: soda ash

– Exhaust Emission (mobile source) CO: Carbon Monoxide [NO2(g)]: Nitrogen oxides

[O3(g)]: Ozone

VOC production

Size Distribution

• Number of particles in Red • Area of particles in dashed lines • Volume of particles in dotted lines• Claremont, California, August 1987

PM2.5

Health Impact with PM2.5

• Sensitive Areas– Near freeway / high traffic area– Airport / harbor – Downwind from industry

• Sensitive Groups – Asthma / other lung diseases – Children / Older adults – Chronicle outdoor workers

Don’t live near freeways!!

2007 Statistics

• 6.5k premature death

• 1.3million school absence days

• 2.8million working days

• 1.7 million asthma patients

• 9000 hospitalized related to respiratory illness

Los Angeles Air Quality Index

2002 AQI

Current LA Emissions vs. World EmissionsSOx 2002

• Data is in (ug/m^3), 150 ug/m^3 per column

• In many countries, the Sulfur content is highly restricted

• fuel, and power production restrictuions

• Many cities stopped monitoring sulfur concentration

• Bottom city Guiyang, China • Top City Nice, France

Current LA Emissions vs. World EmissionsNOx

• 60 ug/m3 pre column

• Bottom city Kiev Ukraine • Top city Porto, Portugal

Current LA Emissions vs. World EmissionsO3

• 200(ug/M^3) pre column

• L.A O3 concentration

• Riverside O3 concentration

Current Monitors

• EPA – CO– NOx– SOx

– O3

– PM2.5

– PM10

– Lead – Facility monitoring

www.epa.gov/air/data/geosel.html

• AQMD

– Collaboration from multi-agencies

– Local

– National

– forecast maps

– current conditions

www.airnow.gov/index.cfm?action=airnow.fcsummary

Geography

L.A Ozone trend

Azusa Ozone trend

Upland Ozone trend

sixteen year projectionwith national standard

L.A Geography

Local Meteorology

• Initial stage

• Initial Mixing

• Development

• Stabilization

Initial Stage

• Stratified Atmosphere • Diminishing Land breeze• Start Valley breeze

LAX

WHIT

ANAH

ONT

8AM Time

Initial Mixing

• After morning traffic• Initial sea breeze

LAX

WHIT

ANAH

ONT

12PM

Development

• Marine Layer propagation• Max temperature contrast

LAX

WHIT

ANAH

ONT

3PM Time

Stabilization

• Marine Layer propagation• Return Flow

LAX

WHIT

ANAH

ONT

5PM Time

Effects

• Wind Speed

• Soil Moisture

• Temperatures

Soil Moisture

NGEs: Normalized gross errors, NG: normalized biases,

Soil Moisture

• Low Soil Moisture

• Destabilize BL

• Increase Mixing

• Decrease Pollutants Concentration

• High Soil Moisture

• Stabilize BL

• Decrease Mixing

• Increase Pollutants

Concentration

Soil Effect

Base Simulation15% Soil Moisture23% Soil Moisture

O3 Concentration

Geography

Hawthorne

• CO

• NOx

• SOx

• Reactive Organic Gases (ROG)

• Total Organic gas• PM2.5

• 486.6• 96.7• 15.9• 102.7

• 218.1• 26.3

Tons per day (2010) 1987

http://www.arb.ca.gov/app/emsinv/fcemssumcat_query.php

• 9796• 889.5• 113.5

• 2429

Transport

Transport

Increasing secondary pollutants

Weekend Effect

Summary

• L.A air quality – Chemistry – Health effect– Historical trend – Compare to the

world – Future projection

• L.A meteorology – Dinural evolution – Effects of primary and

secondary pollutants– “ The Weekend Effect”