Interpolations of Ambient Air Pollution Concentrations in Austin and Houston

1
Interpolations of Ambient Air Pollution
Concentrations in Austin and Houston

• Heather Simon

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Importance of Air Pollution Monitors

• Show compliance with EPA standards
• Alert communities if pollutant concentrations
  reach a level that poses an immediate risk
• Provide valuable data to scientists studying air
  pollution chemistry

3
TCEQ Monitoring System

• 212 monitors in Texas
• 63 monitors in Houston/Galveston region
• Measure meteorological conditions
• Wind speed
• Wind direction
• Solar flux
• Temperature
• Measure pollutant concentrations
• NOx
• ozone
• PM2.5
• CO
• SO2

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View of Monitoring Stations
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Objectives

• Map pollutant concentrations for a specific air
  pollution episode (June 2, 2005)
• Show where pollution concentrations are
  good/moderate/dangerous
• Compare Houston to Austin
• Discuss sources of pollution
• Interpolate pollution data to visualize
  concentrations in areas other than at monitoring
  locations
• Determine where more monitors are most needed
• Locations of highest uncertainty
• Locations where high uncertainties overlap for
  multiple pollutants
• Locations where air quality is bad

6
Imported Data Layers
images of all the layers that were imported.
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Pollution Data
8
Ozone Air Quality Index
Air Quality Index Concentration (ppb) Recommendations
Good 0-80
Moderate 81-120 Unusually sensitive people should consider reducing prolonged or heavy exertion outdoors.
Unhealthy for Sensitive Groups 121-160 Active children and adults, and people with lung disease, such as asthma, should reduce prolonged or heavy exertion outdoors.
Unhealthy 161-200 Active children and adults, and people with lung disease, such as asthma, should avoid prolonged or heavy exertion outdoors. Everyone else, especially children, should reduce prolonged or heavy exertion outdoors.
Very Unhealthy 201-400 Active children and adults, and people with lung disease, such as asthma, should avoid all outdoor exertion. Everyone else, especially children, should avoid prolonged or heavy exertion outdoors.
Hazardous Greater than 400 Everyone should avoid all physical activity outdoors.
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Ozone Concentrations
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Wind Data

• TCEQ emissions plume animation

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Interpolations
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Uncertainties
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Masks for Low Pollutant Areas
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Conclusions

• Ozone did reach levels of concern in Houston
• Mapping and interpolation allowed us to see a
  clear spatial trend in ozone concentrations
• Wind data showed that most ozone in Houston
  originated from the industrial areas, not the
  urban core
• Based on uncertainty in ozone interpolations,
  monitors should be placed to the north and
  southwest of the city
• Since ozone concentrations are low to the
  southwest, first priority should be put on the
  northern monitors
• Note of caution conclusions drawn from a single
  day of data may not be universally applicable

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Data Sources

• County, city, urban area, highway, and monitoring
  point layers were obtained from the Texas Natural
  Resource Information System.
• http//www.tnris.state.tx.us/DigitalData/data_ca
  t.htm
• Pollutant concentrations and meteorological data
  were obtained from the Texas Commission on
  Environmental Quality.
• http//www.tceq.state.tx.us/cgi- bin/compliance/
  monops/daily_summary
• Air Trajectories were obtained from the National
  Oceanographic and Atmospheric Administration.
• http//www.arl.noaa.gov/ready/open/hysplit4.html
  
• Air Quality Index information was obtained from
  the United States Environmental Protection
  Agency.
• http//airnow.gov/index.cfm?actionstatic.public
  ations

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Acknowledgements

• Dr. Maidment
• GIS classmates