Presentation to the Air Quality Forum – August 9, 2005

Clark County Regional Ozone and Precursors Study (CCROPS)

Robert A. Baxter, CCMT & B Systems, Inc.

Background

EPA issued the nonattainment designation for the 8-hour ozone NAAQS in 2004

Clark County DAQEM charged with preparation of attainment and maintenance plans

Characterization of ozone episodesKnowledge and understanding of various

meteorological and air quality conditions leading to exceedances

Ozone Studies

Emissions studies– Inventories

– Emissions

– Control measures

2004/2005 CCROPS– Ozone characterization study

– 2005 field study

CCROPS Objectives

Obtain a data set to help understand the origin of ozone and precursors

Assess the adequacy of the Clark County monitoring network to measure peak ozone

Obtain a data set of known quality for model validation

Generate a database for current and future SIP development

Provide recommendations for future research to support modeling of ozone

CCROPS MeasurementsUpper Air Meteorology

Radar wind profilerSodarsRawinsondesPilot balloonsGlider temperature

CCROPS MeasurementsSurface Ozone and Meteorology

Supplemental ozone measurements (10)

Boundary (2)Saturation ozone

measurements (13)

CCROPS MeasurementsSurface Ozone and Meteorology

Supplemental ozone measurements (10)

Boundary (2)Saturation ozone

measurements (13)

CCROPS MeasurementsSurface Ozone and Meteorology

Supplemental ozone measurements (10)

Boundary (2)Saturation ozone

measurements (13)

CCROPS MeasurementsUpper Air Ozone

OzonesondesAircraft

CCROPS MeasurementsUpper Air Ozone

OzonesondesAircraft

CCROPS MeasurementsUpper Air Ozone

OzonesondesAircraft

CCROPS MeasurementsUpper Air Ozone

OzonesondesAircraft

July 1 -- Aircraft Flight 0740 PDT Jean Sounding

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 10 20 30 40 50 60 70 80 90 100

Alt

itu

de

(m m

sl)

PM10 (ug/m3) Ozone (ppb) Temperature (C)

Ozone

Temperature

PM10

CCROPS MeasurementsPrecursor and Reactive Species

Volatile Organic Compounds (VOCs)Nitrogen species (NO2, PAN, NOy, Nitric

Acid)Enhanced DAQEM NO/NOx/NO2

Ozone Site Locations

Ozone Site Locations

Ozone Site Locations

Ozone Site Locations

Sampling Schedule

Study Period = May 1 – August 31Intensive Operational Periods (IOPs)

– May 15 – August 31– Four periods, 1 to 2 weeks in duration– Added rawinsondes and saturation ozone

Episodes– 15 forecasted days within IOPs– Added ozonesondes, VOCs and aircraft

What Have We Seen?

Ozone Patterns Similar from Characterization Study Years

Transport Scenarios Significant Ozone Production from

Regional Fires

Questions?

Please contact:

Department of Air Quality and Environmental Management

(DAQEM)

(702) 455-5942