Houston High Ozone October 9, 2008
Images
- Ozone Animation
- Plume Animation
- Back Trajectory Bayland Park CAMS 53 3pm
- Back Trajectory Bayland Park CAMS 53 4pm
- Back Trajectory Bunker Hill CAMS 562 4pm
- Back Trajectory Bunker Hill CAMS 562 5pm
- Back Trajectory Bunker Hill CAMS 562 6pm
- Back Trajectory Katy Park CAMS 559 4pm
- Back Trajectory Katy Park CAMS 559 5pm
- Back Trajectory Katy Park CAMS 559 6pm
- Back Trajectory West Houston CAMS 554 5pm
- Back Trajectory West Houston CAMS 554 6pm
- Satellite Image False Color - East Texas 3:52 am CDT (from UT CSR)
- Satellite Image False Color - East Texas 7:04 am CDT (from UT CSR)
- Satellite Image False Color - East Texas 11:16 am CDT (from UT CSR)
- Satellite Image True Color - East Texas 11:43 am CDT (from UT CSR)
- Satellite Image True Color - Houston 11:43 am CDT (from UW SSEC)
- Satellite Image True Color - Houston 2:57 pm CDT (from UW SSEC)
- Winds Aloft at La Porte
- Winds Aloft at La Porte Mid-Day
Description
High ozone was measured on the west and southwest side of the Houston area on Thursday, October 9th. The highest measured eight-hour average was 90 parts per billion (ppb) at the Bunker Hill Continuous Ambient Monitoring Station (CAMS) 562 and rated as Level Orange, Unhealthy for Sensitive Groups, on the U.S. Environmental Protection Agency (EPA) Air Quality Index (AQI)
scale. The highest measured one-hour average was 138 parts per billion (ppb) for the hour from 4:00 to 5:00 p.m. Central Daylight Time (CDT), at West Houston CAMS 559. Level Orange ozone was measured at five sites, with "Moderate" or higher ozone at 18 sites out of 36 sites reporting complete data for the day. This day was the 33rd day with Level Orange or higher ozone measurements, based on the new ozone standard and AQI. It was the 14th day with measured levels exceeding the old 8-hour ozone standard.
Skies were clear all day. Winds were light from the northeast in the early morning and then shifted to the east in the late morning and to the southeast in the afternoon. The high temperature was 82 degrees Fahrenheit (°F) at George Bush Houston Intercontinental Airport, 81°F at Hobby Airport, and 84°F at Galveston Airport.
Regional background levels of ozone coming into the Houston area were around 48 to 53 ppb as indicated by the peak eight-hour averages at Conroe CAMS 78, Kingwood CAMS 555, and Crosby CAMS 553. The difference of 47 to 52 ppb between the measured eight-hour area maximum and the approximate regional background level was likely caused by local air pollution sources in the Houston area. The approximate local contribution was about 52 to 59 percent of the measured 90 ppb area eight-hour peak.
The Plume Animation shows the estimated plume tracks from large industrial sources of oxides of nitrogen (NOx) and volatile organic compounds (VOC), along with the plume tracks for the centers of the broad urban plumes coming from downtown Houston and other major urban centers. The plume animation suggests that urban and industrial emissions from the Houston Ship Channel area were in the vicinity of some of the highest ozone measurements.
