1. Phoenix Metropolitan Area Urban Nephelometer Program Mike Sundblom Arizona Department of Environmental Quality April 13, 2005

2. Network History Phoenix Urban Haze Program Network began in early 1990’s with 1 transmissometer path, 1 nephelometer at JLG Supersite, and a network of Dichotomous Pm 10/fine samplers Network began in early 1990’s with 1 transmissometer path, 1 nephelometer at JLG Supersite, and a network of Dichotomous Pm 10/fine samplers Expanded in 2003 through a recommendation from the 2000 Governor’s Brown Cloud Summit Expanded in 2003 through a recommendation from the 2000 Governor’s Brown Cloud Summit Expansion included: Expansion included: 3 nephelometers 1 transmissometer path 4 camera systems Website – www.phoenixvis.net Website – www.phoenixvis.net

3. Locations and Equipment

4. Purpose and Use Track Long Term Visibility Trends in Urban Area Track Long Term Visibility Trends in Urban Area Report Visibility Parameters to the Public (Phoenix area Visibility Index) AIRNOW Reporting of PM2.5 PM2.5 Forecasting

5. AIRNOW Reporting How does Arizona report nephelometer (Bscat) as PM2.5? A relation between nephelometer Bsp and PM2.5 reference measurement needed A relation between nephelometer Bsp and PM2.5 reference measurement needed EPA funded this work in 2003 at two urban locations – Phoenix and Tucson EPA funded this work in 2003 at two urban locations – Phoenix and Tucson Work conducted by Battelle ( David Wendt and Nancy McMillan) Work conducted by Battelle ( David Wendt and Nancy McMillan)

6. AIRNOW Reporting FRM PM2.5 Data All data is from the Phoenix Supersite All data is from the Phoenix Supersite Obtained from AQS Obtained from AQS 161 observations during 2002 161 observations during 2002 Daily from January 1 through March 31 Daily from January 1 through March 31 Every sixth day from April 1 through May 7 Every sixth day from April 1 through May 7 Every third day from May 8 through December 31 Every third day from May 8 through December 31

7. AIRNOW Reporting Dichot data All data from Phoenix Supersite All data from Phoenix Supersite Included fine, coarse, and total PM – analysis focused on fine. Included fine, coarse, and total PM – analysis focused on fine. 45 Observations during 2002 45 Observations during 2002 February 2 to December 28 February 2 to December 28 Data only every six days Data only every six days

8. AIRNOW Reporting Nephelometer Data Obtained from IMPROVE website Obtained from IMPROVE website 2002 Data from Phoenix Supersite 2002 Data from Phoenix Supersite Hourly measurements of Bsp and relative humidity averaged to provide daily observations Hourly measurements of Bsp and relative humidity averaged to provide daily observations

9. AIRNOW Reporting Individual hourly nephelometer measurements transformed to FRM-like using the equation: Nephelometer (FRM-Like) DichotFRM 1.000.780.89 Dichot0.781.000.95 FRM0.890.951.00 Correlation (R)

10. AIRNOW Reporting January-June 2002 Battelle

11. AIRNOW Reporting July-December 2002 Battelle

12. Nephelometer Sites Reported to AIRNOW

13. Data Comparison

14. Phoenix Supersite December 2, 2004 24-Hr PM2.5 Concentrations (µg/m3) PM2.5 Neph FDMS TEOM PM2.5 BAM FRM (Filter) 23.927.126.628.1

15. AIRNOW Reporting Limitations….Questions?