Nealson Watkins & Dennis Mikel EPA - Office of Air Quality, Planning and Standards

1. Technical Support of NCore Implementation: Meteorological Requirements Nealson Watkins & Dennis Mikel EPA - Office of Air Quality, Planning and Standards

2. Outline • Introduction • NCore Requirements • Sensors (Calibrations and QA issues) • Siting • Sonic Anemometers • Equipment miniaturization • Data Handling Issues • Data Acquisition Systems • Overview of the revision of the QA Handbook, Volume IV: Meteorological Measurements

3. Currently only required for PAMS sites (~ 92 sites) However, many S/L/Ts measuring even without a requirement Reporting to AQS and/or AIRNow Approximately 31 users submitting to AIRNow-Tech The State of State, Local, and Tribal Meteorological Monitoring AIRNow-Tech Navigator illustrating PM2.5 and Wind barbs

4. Met Data Reported to AQS* As of 1/22/07 *Sites shown do not necessarily report more than one parameter

5. What is meteorological data supposed to do for us? • Used as supportive data at multi-pollutant sites (re: NCore) And who wants all this supportive meteorological data? • Modelers • Data Analysts • Forecasters

6. Primary Issue: Many State/Local agencies are hesitant to use the meteorological data they collect because of uncertainty in data quality. Several State/Local agencies have trouble accessing meteorological data both from their own agency and from neighboring agencies. Some traditional meteorological monitoring methods (e.g. siting criteria) are not appropriate for air quality applications. Possible Solution: Quality Assurance (QA) requirements at NCore multi-pollutant sites to promote better data quality. Enhance EPA’s databases (e.g. AIRNow and AQS) to improve their capability for storing and sharing meteorological data. Create measurement methods specific to meteorological monitoring for air quality management. Specifically, investigate ways to appropriately use met data from a site that may not be “perfect.” What are some known S/L/T issues with reporting meteorological data?

7. So why all the attention on meteorological data that’s currently NOT required?? NCore

8. NCore Design Criteria • 40 CFR 58 Appendix D.3.b states, “The NCore sites must measure, at a minimum, PM2.5, ….wind speed, wind direction, relative humidity and ambient temperature.” • Additional parameters may include: • Solar Radiation • Precipitation • Barometric Pressure • Wind data in vector format!

9. NOAA vs. S/L/T Met Data • S/L/Ts provide hourly averaged data • NOAA data is a 2 minute average taken 10 to 20 minutes before the top of the hour • S/L/T wind data can be vector averaged! • NOAA wind data is scalar only • Vector data is needed to follow (model) air parcel movements • S/L/T met. data will be co-located with air pollution data • S/L/T data may represent multiple siting scales • Regional, Neighborhood, Middle, & Microscale

10. Tools of the trade… • Wind speed • Wind direction • Ambient Temperature • Relative humidity

11. Additional Instrumentation • Barometric Pressure • Solar Radiation • Precipitation *EPA’s reference to certain product types or brand-names does not translate into endorsement.

12. Siting Issues • Siting is very critical, as it directly determines what the data represent • The Issue: Siting for air pollution monitoring doesn’t always allow for ideal siting for meteorological monitoring • The Solution: Focus on NCore sites, and reference the revised QA Handbook for non-NCore sites.

13. Ideal Siting Criteria Note: More details on siting and exposure are available in the individual sections of the QA Handbook. Please see the installation section of each chapter for more information.

14. Siting issues with towers • Section 2.4 of QA Handbook is updated. • Ideally, NCore sites will follow NWS type setup • The remaining majority of sites likely will have more relaxed criterion • Remember: EPA can only make recommendations!

15. QA Issues • In most instances, Met data are collected for: • Forecasting • Modeling • Data Analysis • Public consumption • Since Met data is supportive, generally, DQOs don’t need to be generated. Without DQOs, how do we get the Measurement Quality Objectives (MQOs)? • The answer: QA Handbook has tables of MQOs for programs that recommend or require Met data

16. Suggested NCore Measurement Quality Objectives

17. Suggested NCore Calibration/Audit Recommendations

18. Sonic Anemometers • “Sonics” are a relatively new to our market • Use time-of-flight of sonic impulses to determine wind speed and direction • Pros: • High Sensitivity • No moving parts • Cons: • Harder to QA and calibrate in the field

19. Electrical hiccups can occur Data interpretation can be slightly different Sonic Data Issues • Example1: When winds • go to calm conditions, • what happens to the • wind direction? • Do we want to emulate • old systems for data • continuity purposes? • Example2: How much • of an issue is eddy • turbulence? • Either “Self” produced • or from nearby obstacle?

20. Miniaturization • Several vendors now have miniature weather stations available • Climatronics & Vaisala • OAQPS is obtaining one of each unit for evaluation purposes • Vendors claim accuracy and resolution metrics within those in the suggested NCore MQO table • Could be an answer for some QA issues associated with sonic and other methods (think co-location)

21. Climatronics Includes: WS, WD, T, RH and self-orients to North Vaisala Includes: WS,WD, T, RH and precipitation Miniature Met Stations

22. Wind DataScalar Data vs. Vector Data • Overall difference is more apparent at lower wind speeds • Scalar: using arithmetic average • Vector: either directly obtain or derive orthogonal components from scalar values • In the case of wind speed, vector-averaged speeds are never larger than the scalar-averaged values and generally are lower • Example: 10 minute total average • North wind at 5 m/s for 5 minutes • South wind at 5 m/s for 5 minutes • Scalar average: 5 m/s & Easterly (90°) heading • Vector average: 0 m/s & No net movement

23. Data Handling

24. Data Handling • Once we’re sited and running, it’s time to review and move the data • Many sensors providing analog data to a translator (esp. wind data) • Translators typically can output digitally or analog • Vector averaging requires conversion from scalar (by translator or data acquisition system)

26. Organize & move that data… The goal: Timely reporting of high quality, highly time-resolved ambient monitoring data. • Data acquisition system is key • Digital or analog (we like digital! ) • Disseminate locally and/or nationally • Move it where? • AQS • Local users (AQ forecasters, etc.) • AIRNow-Tech

27. Public medium Focused on the Air Quality Index (AQI) Current pollutant data (maps & data) Forecast products AIRNow

28. NOT public Controlled access; users only Data access Reporting status Tables “Navigator” GUI AIRNow-Tech

29. AIRNow-Tech Evolution • Launched mid-2003 • Allowed access to all the hourly pollutant data • Two subsequent upgrade versions (2005 & 2006) • 2005 and 2006 improvements • New OBS data file formatting • Temporary site accommodations • Improved data display graphics • Interactive GIS based “Navigator” interface • Increased acceptable data parameters

30. Increased Reportable Parameters Current Parameters Required naming convention Precursor Gas Parameters Speciation Parameters Meteorological Parameters Precipitation Precip Millimeters

31. AIRNow-Tech Navigator

32. HYSPLIT Trajectories in Navigator

33. Overview of the Red Book • There was a strong need to update the older QA Handbook Volume IV • Newer technologies • Digital Data Acquisition • New 40 CFR 58 Requirements (i.e., NCore) • 1st Draft revision comments are due back to OAQPS on 2/28/07 for review and incorporation • First pass revision and review included S/L/T operators, NOAA staff, and private/contract industry staff • 2nd Draft will be more openly available for review • Air Mon Listserv shall be used to distribute

34. What’s New: Towers Installations of Towers Types of Towers Available Tower Support

35. What’s New: Wind Systems Section 2 discusses Cup and Vane Systems Calibrations, torque test and distance constants Section 2 discusses Propeller and Vane Systems

36. What New: Wind Systems There is a great discussion on Magnetic Declination for wind direction traceability Detailed discussion on Solar Noon method for wind direction traceability

37. What’s New: Wind Systems Section 2 has in-depth discussion of sonic anemometers The Handbook illustrates some side by side comparisons of prop vs. sonic

38. What’s New: Data Validation In-depth discussion of data validation Section discusses validation and verification Discusses how to “link” met data to pollution data Each “type of review” has a section number

39. Other topics included in the Handbook: • Multiple tables of MQOs • Illustrate differences between applications (PSD, PAMS, NCore, and others) • Data acquisition and validation • Upper Air Systems • OAQPS is also creating how-to video as an accompaniment to the new version

40. Summary • EPA would like to see more of the existing data shared within our air monitoring communities (via AIRNow-Tech, AQS, local users) • New monitoring requirements are the driver behind our renewed interest in met data • Our goal is to provide appropriate, and updated guidance to S/L/Ts