Interpolations of Ambient Air Pollution Concentrations in Austin and Houston

Heather Simon

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

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

View of Monitoring Stations

Objectives

1. 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

2. Interpolate pollution data to visualize concentrations in areas other than at monitoring locations

3. 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

Imported Data Layers

Pollution Data

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.

Ozone Concentrations

Wind Data

TCEQ emissions plume animation

Interpolations

Uncertainties

Masks for Low Pollutant Areas

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

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_cat.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?action=static.publications

Acknowledgements

Dr. Maidment GIS classmates