Exploring a Pollution Event

Transcription

1 Exploring a Pollution Event Glenn Gehring, Technology Specialist III Tribal Air Monitoring Support (TAMS) Center Institute for Tribal Environmental Professionals (ITEP) Northern Arizona University glenn.gehring@nau.edu

2 What Do These Data Mean? Vertical manifold Tubing for NOy Continuous Particulate Sensor Unit Toxics Flow Controller Data Logger Calibrator Gas Analyzer Rack NOy NOx SO2 316 Stainless Steel 1/8 inch tubing connects regulator to calibrator Continuous Particulate Monitor Control Units Zero Air Generator Ozone CGA 660? Fitting must match bottle EPA Protocol Gas

3 Two big factors related to pollutant dispersion: Ventilation Index (horizontal movement) Stability (vertical mixing)

4 Mixing Height & Wind = Ventilation Index Mixing Height Wind

5 NOAA ARL Stability Forecast Zi - Boundary layer depth (meters above model terrain) 10xKz - Vertical mixing coefficient times 10 (m2/s2) A Extremely Unstable B Moderately Unstable C Slightly Unstable D Neutral E Slightly Stable F Moderately Stable G Extremely Stable Includes an indication of upward push

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7 Ozone and PM-2.5 Readily Transport long distances and React in the Atmosphere Ozone is the Product of a Reaction Initiated by Light (Photochemical Reaction) in the Atmosphere; Ozone Precursors, such as NOx and VOCs are Emitted From Sources

8 Very important chemical reactions related to ozone:

9 Ozone Diurnal (daily) Patterns

10 Quapaw Site on July 22, 2004 Site s highest 8-hr Ozone 93 ppb as an 8-hour average

11 What were other 8-Hour ozone concentrations on July 22, 2004?

12 I selected ozone for one state at a time and merged the resulting data in a spreadsheet.

13 Since these data have spatial references for each monitoring site (lat, long) I can easily put this data into GIS software. Then I can use gradients to make higher concentrations appear as larger circles on the map.

14 Area 8-hr Ozone on July 22, 2004 Kansas City Saint Louis Quapaw Site Oklahoma City Tulsa Little Rock Memphis

15 I can also use GIS extensions to help illustrate. 8-hr Ozone on July 22, 2004 with Prediction Contours (ESRI Geostatistical Analyst) Quapaw Site

16 I can use Air Data or other resources to get point source emissions data, map it and make the size of the circles proportional to emissions. I can also use NOAA s Air Resources Laboratory s HYSPLIT software to perform backward trajectories from monitoring sites on the day of concern.

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18 July 22, 2004, 24-hour Backward Trajectories (NOAA Air Resource Laboratory HYSPLIT Model) proportional NOx point source emissions 2002 EI Quapaw Site

19 Now I have some suspect areas that may have contributed to the problem (something near the three coal-fired power plants). I can use ARL s HYSPLIT software to run forward dispersions from the power plants to see where the model indicates their emissions were when I had the high concentration. In this example I set the model to average concentrations from 100 m to ground level and set it for a 48-hour release beginning 48-hours prior to the high concentration at the Quapaw site.

20 Oologah Power Plant 48-hr dispersion (NOAA Air Resource Laboratory HYSPLIT Model) Quapaw Site

21 GRDA Power Plant 48-hr dispersion (NOAA Air Resource Laboratory HYSPLIT Model) Quapaw Site

22 Muskogee Power Plant 48-hr dispersion (NOAA Air Resource Laboratory HYSPLIT Model) Quapaw Site

23 Combined 48-hr dispersion (NOAA Air Resource Laboratory HYSPLIT Model) Quapaw Site

24 Forward Trajectory from 3 Coal-Fired Power Plants on July 22, 2004 (endpoints that are less than 10 meters AGL)

25 Forward Trajectory from 3 Coal-Fired Power Plants on July 22, 2004 (endpoints that are less than 20 meters AGL)

26 WIND ROSE PLOT Most Relevant Winds for Ozone Station # TULSA/INT'L ARPT, OK Tulsa Ozone Season Wind Rose, NORTH Lines Indicate the Direction the Wind Came FROM, and Colors Indicate Wind Speed ( , March 1 to October 31, from 8 AM to 6 PM) N 20% 25% NE Oklahoma Coal-Fired Power Plant NOx Emissions Source: EPA AirData (1999 EI) What if you live here? 15% 10% W WEST 5% E EAST SSOUTH 2003 Ozone Monitoring Locations (Red Dots) 26.5% of Oklahoma facility NOx emissions are from Muskogee, Mayes and Rogers Counties (1999) 22.9% of Oklahoma facility NOx emissions are from three NE Oklahoma coal-fired power plants (1999)

27 GIS for Air Quality Course