Phoenix Metropolitan Area Urban Nephelometer

Program

Mike Sundblom

Arizona Department of Environmental Quality

April 13, 2005

Network HistoryNetwork History

Phoenix Urban Haze ProgramPhoenix Urban Haze Program Network began in early 1990’s with 1 Network began in early 1990’s with 1

transmissometer path, 1 nephelometer at JLG transmissometer path, 1 nephelometer at JLG Supersite, and a network of Dichotomous PmSupersite, and a network of Dichotomous Pm10/fine10/fine samplerssamplers

Expanded in 2003 through a recommendation from Expanded in 2003 through a recommendation from the 2000 Governor’s Brown Cloud Summitthe 2000 Governor’s Brown Cloud Summit

Expansion included: Expansion included: 3 nephelometers3 nephelometers1 transmissometer path1 transmissometer path4 camera systems4 camera systems Website – www.phoenixvis.netWebsite – www.phoenixvis.net

Locations and EquipmentLocations and Equipment

Purpose and UsePurpose and Use

Track Long Term Visibility Trends in Track Long Term Visibility Trends in Urban AreaUrban AreaReport Visibility Parameters to the Public Report Visibility Parameters to the Public (Phoenix area Visibility Index)(Phoenix area Visibility Index)AIRNOW Reporting of PM2.5AIRNOW Reporting of PM2.5PM2.5 Forecasting PM2.5 Forecasting

AIRNOW Reporting AIRNOW Reporting

How does Arizona report nephelometer How does Arizona report nephelometer (Bscat) as PM2.5?(Bscat) as PM2.5? A relation between nephelometer Bsp and A relation between nephelometer Bsp and

PM2.5 reference measurement needed PM2.5 reference measurement needed EPA funded this work in 2003 at two urban EPA funded this work in 2003 at two urban

locations – Phoenix and Tucsonlocations – Phoenix and Tucson Work conducted by Battelle (Work conducted by Battelle (David Wendt and David Wendt and

Nancy McMillan)Nancy McMillan)

AIRNOW ReportingAIRNOW Reporting

FRM PM2.5 DataFRM PM2.5 Data All data is from the Phoenix SupersiteAll data is from the Phoenix Supersite Obtained from AQSObtained from AQS 161 observations during 2002161 observations during 2002

Daily from January 1 through March 31Daily from January 1 through March 31 Every sixth day from April 1 through May 7Every sixth day from April 1 through May 7 Every third day from May 8 through December 31Every third day from May 8 through December 31

AIRNOW ReportingAIRNOW Reporting

Dichot dataDichot data All data from Phoenix SupersiteAll data from Phoenix Supersite Included fine, coarse, and total PM – analysis Included fine, coarse, and total PM – analysis

focused on fine. focused on fine. 45 Observations during 200245 Observations during 2002

February 2 to December 28 February 2 to December 28 Data only every six daysData only every six days

AIRNOW ReportingAIRNOW Reporting

Nephelometer DataNephelometer Data Obtained from IMPROVE websiteObtained from IMPROVE website 2002 Data from Phoenix Supersite 2002 Data from Phoenix Supersite Hourly measurements of Bsp and relative Hourly measurements of Bsp and relative

humidity averaged to provide daily humidity averaged to provide daily observationsobservations

AIRNOW ReportingAIRNOW ReportingIndividual hourly nephelometer measurements Individual hourly nephelometer measurements transformed to FRM-like using the equation:transformed to FRM-like using the equation:

2RelHum*0001.0RelHum*0053.0)BSP*log(8328.06041.0likeFRM e

Nephelometer Nephelometer (FRM-Like)(FRM-Like)

DichotDichot FRMFRM

Nephelometer Nephelometer (FRM-Like)(FRM-Like)

1.001.00 0.780.78 0.890.89

DichotDichot 0.780.78 1.001.00 0.950.95FRMFRM 0.890.89 0.950.95 1.001.00

Correlation (R)

AIRNOW ReportingAIRNOW Reporting

0

10

20

30

40

50

PM2.5 Nephelometer Dichot FRM

January-June 2002

Battelle

AIRNOW ReportingAIRNOW Reporting

0

10

20

30

40

50

PM2.5 Nephelometer Dichot FRM

July-December 2002

Battelle

Nephelometer Sites Reported to Nephelometer Sites Reported to AIRNOWAIRNOW

Data ComparisonData ComparisonComparison of FDMS TEOM and PM2.5 NEPH

Phoenix Supersite Dec 1- 4, 2004

0

10

20

30

40

50

60

70

80

90

100

12/1

12:

00

6:00

12:0

0

18:0

0

12/2

12:

00

6:00

12:0

0

18:0

0

12/3

12:

00

6:00

12:0

0

18:0

0

12/4

12:

00

6:00

12:0

0

18:0

0

Rela

tive

Hum

idity

%

RH FDMS Neph2.5 BAM PM2.5

Data ComparisonData Comparison

Phoenix Supersite Phoenix Supersite December 2, 2004 December 2, 2004

24-Hr PM2.5 Concentrations (µg/m3)24-Hr PM2.5 Concentrations (µg/m3)

PM2.5 NephPM2.5 Neph FDMS TEOMFDMS TEOM PM2.5 BAMPM2.5 BAM FRM (Filter)FRM (Filter)

23.923.9 27.127.1 26.626.6 28.128.1

AIRNOW ReportingAIRNOW Reporting

Limitations….Limitations….

Questions?Questions?