EPA TEMPO Activities Update: PAMS Redesign, Pandora Collaboration, and Enhanced Monitoring Plan

1. Update on EPA TEMPO Activities EPA:Jim Szykman, Luke Valin,Andrew Whitehill, Kevin Cavender, David Williams, Russell Long + NASA: Bob Swap, Barry Lefer, Jay Herman, Nader Abuhassan, Alexander Cede (NASA/ESA), Travis Knepp (SSAI) + Harvard Smithsonian: Kelly Chance Virginia Tech: Elena Lind UMBC: Ruben Delgado and Vanessa Caicedo Plus NJDEP, NYDEC, CTDEEP, plus many others Email:Szykman.Jim@epa.gov and Valin.Lukas@epa.gov TEMPO Science Team Meeting June 6-7, 2018 NCAR Boulder, CO

2. Talk Outline • EPA Photochemical Assessment Monitoring Station Network Redesign • PAMS and Pandora • East Coast BEACON • Ceilometers • Formaldehyde • Summary

3. Redesign of the PAMS Network • Major changes to the PAMS requirements were finalized in October 2015 as part of the ozone NAAQS review • EPA replaced the existing 20 year-old multi-site, enhanced ozone network design with an updated 2-part network design: • Requiring PAMS measurements to be collocated with existing NCore sites in areas with population of 1 million or more irrespective of Ozone NAAQS attainment status • Results in a stable network of approximately 40 required sites with improved spatial distribution and reduced redundancy • Includes a waiver for historically low ozone areas • Includes an option to make PAMS measurements at an alternative location (e.g., an existing PAMS site) which may cross CBSA or even state boundaries • Require states with moderate or above ozone non-attainment areas and states in the Ozone Transport Region to develop and implement an Enhanced Monitoring Plan (EMP) • Provides support for flexible approaches for collecting data to understand ozone issues in new and existing high ozone areas • States need to comply with the new PAMS monitoring requirements (begin operation) at NCore sites by June 1, 2019. Enhanced Monitoring Plans will be due within two years after EPA designates nonattainment areas or by Oct. 1, 2019*, whichever is later. (Designations made for most counties on November 6, 2017.)

4. TEMPO Relevant Changes under PAMS Redesign • Requires 3 8-hr carbonyls samples on a 1 in 3 day schedule • Included an alternative to allow for continuous formaldehyde measurements • Requires “true NO2” in addition to existing NOy • Requires hourly mixing height measurement (replaces “upper air measurements”) • Added a waiver option to allow measurements to be made at an alternative location (e.g., NOAA ASOS sites) • Require states with moderate or above ozone non-attainment areas and states in the Ozone Transport Region to develop and implement an Enhanced Monitoring Plan (EMP)

5. EPA is working with the NASA Pandora Project to develop a subset of surface air quality sites to host Pandora spectrometer instruments and contribute to larger Pandonia Global Network. Facilitated by Agency level EPA-NASA Memorandum of Agreement and TEMPO mission. Initial focus is on deployment of Pandora as part of the Enhanced Monitoring Plan (EMP) requirements under the redesigned Photochemical and Assessment Monitoring Stations (PAMS) along with a select number of CASTNet sites. DISCOVER-AQ, KORUS-AQ, plus other campaigns demonstrated Pandora is highly relevant to air quality and ability to provide observations of key O3 precursors -NO2 and HCHO. Initial PAMS-EMP deployment included 9 long-term units (May 2019) within Ozone Transport Region at NYDEP, NYDEC, and CTDEEP sites. This effort also supports the Long Island Sound Topospheric Ozone Study (LISTOS Summer 2018) and on-going S5P TROPOMI validation. EPA-NASA PAMS Pandora Collaboration

6. Phase I PAMS-EMP Deployment New Havn • CO, SO2, true NO2/NOy, O3, PM spec., mixing height, solar rad, BC, MET Hammonasset Outer Island • O3 + met Westport • O3, CAPS NO2, Mlh, + EPA LISTOS HCHO, NOy • EPA assets + F&W assets Flax Pond • CO, CO2, SO2, NOx, O3, Hg, Acid dep, sulfate, PM2.5, carbonyl, toxics, hourly VOC, MET B BG • Future PAMS • O3 and VOC guaranteed for summer 2018. NO2 next priority. • LIDAR, CO, O3, PM, CO2 CCNY QC NY Bayonne • LISTOS-only CO, SO2, NOx, O3, BC, BTEX, MET • CO, SO2, NOx/NOy, O3, PM spec., BC, sulfate, carbonyl, toxics, MET EPA owned Other, with coordination via EPA if needed Rutgers • CO, SO2, NOx, O3, Hg, PM2.5, carbonyl, toxics, hourly VOC, MET

7. Pandora deployment under PAMS in OTR will provide a dense network for validation TROPOMI NO2 over LISTOS Domain The presented work has been performed in the frame of the Sentinel-5 Precursor Validation Team (S5PVT) or Level 1/Level 2 Product Working Group activities. Results are based on preliminary (not fully calibrated/validated) Sentinel-5 Precursor data that will still change. Sentinel-5 Precursor is a European Space Agency (ESA) mission implemented on behalf of the European Commission (EC). The TROPOMI payload is a joint development by ESA and the Netherlands Space Office (NSO). The Sentinel-5 Precursor ground-segment development has been funded by ESA with national contributions from The Netherlands, Germany, and Belgium.

8. Pandoras in the Ozone Transport Region Maine New Hampshire Westport New Haven Hammonasset Outer Island Flax Pond Rhode Island Bronx BG QCNY Rutgers CCNY ACHD PADEP Phase 1 EPA-coordinated. Spring 2018 Phase 2 EPA-coordinated. No later than summer 2019 Ongoing Operations UMBC NASA GSFC NASA HQ McMillan VCU – Rice Center NASA LaRC

9. BEACON East • 7 BEACON nodes in Bronx, Harlem and Fort Lee • Low-cost, low-maintenance sensor packages deployed at reference monitoring sites • Vaisala GMP343 CO2 (±0.5 ppm) Alphasense AQ sensor package (four gases), optical PM sensor • Provides valuable information on NOx emission rates (NOx mass/ CO2 mass) a key uncertainty in developing O3 control strategies • Will provide key information on how surface variations of atmospheric composition relate to spatially-detailed GeoTASO column NO2 measurements Bronx Botanical Garden PAMS supersite I95 GW Bridge Near road High Precision CO, PM2.5, NO2 IS143 PM2.5 mass only GW Bridge New Jersey Morrisania II PM2.5 mass only Bronx CCNY O3 High Precision CO IS52 O3, NOx, toxics, PM speciation, low-level SO2 Manhattan 8 km × 10 km IS45 PM2.5 mass only

10. Ad-hoc Ceilometer Evaluation Study (ACES) • Nov. 15-Dec. 16, 2016 @ UMBC (Catonsville, MD) • EPA/NWS/UMBC Measurements to help guide EPA PAMS program implementation for new hourly MLH requirement and supplement current efforts under NWS ceilometer test bed. Instruments: Campbell Scientific –CS135 (Viewpoint) Leosphere ALS-450 and 200S Windcube (UMBC algorithm) Lufft CHM15K (Firmware 0.73) iMet-1-ABxn 403 MHz GPS Radiosonde Radiometrics MP-3000 Sigma Space Micropulse Lidar Vaisala – CL-31and CL-51 (BLView 1.19), Digicora MW41 (RS-41 and RS-92) Source: R. Delgado,

11. Objectives: • Evaluate the range corrected attenuated backscatter from commercial ceilometers with a focus in the lowest kms. • Assess the daytime mixing layer height determination from commercial ceilometers: • MLH from vendor software vs. common algorithm across systems. • Focus on transition time periods. • What additional information can be gained from ceilometers, such as elevated layers aloft and entrainment? • Begin Prototype Development of Ceilometer Network under PAMS which includes a national archive and implementation of a common algorithm for MLH. Source: R. Delgado,

12. Evaluation of Ceilometers for PAMS Mixing Level Height Requirement in differing Environments DISCOVER-AQ/FRAPPE (Jul-Aug 2014, Denver, CO) Low Aerosol Environment KORUS-AQ (May-Jun 2016, Seoul, S. Korea) High Aerosol Environment UWFPS (Jan-Feb 2017, Utah) High Aerosol w/ Cold Pool Inversions LMOS2017 (May-Jun 2017, Lake Michigan, WI/IL) Low –Moderate Aerosol Land/Water Interface

13. Assessing the state of commercially available continuous HCHO measurements • PAMS requires 3 8-hr carbonyls samples on a 1 in 3 day schedule. Continuous HCHO measurement can be implemented in place of EPA Method TO-11A. • A Laboratory and Field Evaluation and Intercomparison of Ambient Formaldehyde Instruments lead by Andrew Whitehill (EPA-ORD-NERL) is currently planned for summer 2018 • Joshua Shutter (Keutsch Group) working with Aeris Technologies to evaluate performance of IR Absorption method. • City of Houston Health Department and Univ. of Houston (Flynn Group) working with Gasera to evaluate performance of Photoacoustic QCL Method.

14. Aeris Intercomparison with LIF Instruments [Aeris] = 1.015(±0.005)[ISAF] + 0.21(±0.05) [Aeris] = 1.017(±0.005)[CAFÉ] + 0.18(±0.05) R2 = 0.976 R2 = 0.979 The Aeris sensor slightly overpredicts (<2%) when compared against research-grade LIF HCHO instruments. Offsets are less than ±0.3 ppbv. Bivariate least squares regressions were computed using the method of York et al. (2004) Harvard FILIF: Joshua Shutter and Frank Keutsch NASA ISAF and CAFÉ: Glenn Wolfe, Jason St. Clair, Tom Hanisco J. Shutter 6/5/18 Keutsch Group

15. J. Shutter 6/5/18 Keutsch Group Keutsch Grouped developed their own fitting algorithm at Harvard (ICOS) to fit the data and compare it to the mixing ratio being reported by the Aeris sensor. While their fitting algorithm performs slightly better than the Aeris fit by itself, the average of the two fits yields better results.

16. 20+ year Bay Area MDA8 ozone record (since 1995) HCHO concentrations as large as 40 ppb, columns as large as 4e16 in shallow PBL: Role of upwind biomass burning + local biogenic emissions ?

17. KORUS-AQ KORUS provided evaluation of pandora spectrometer retrieval plus use of in-situ HCHO + ceilometer for mixing height to derive HCHO columns. The combination of these continuous measurements collocated can provide an important ground-based validation data set for TropOMI and TEMPO! HCHO QCL Luke Valin pandora ceilometer Spinei, E., A. Whitehill et al., The First Evaluation of Formaldehyde Column Observations by Pandora Spectrometers during the KORUS-AQ Field Study, AMTD 2018,

18. KORUS-AQ Measured and Median MLH

19. Stratosphere Pandora Slant Column Vertical Stratospheric NO2 Column ~15 km Satellite Slant Column (along light path) • ΩS – Slant NO2 column • ΩV - Vertical NO2 Column • ΩV = ΩS/AMF • AMF – air mass factor are sensitive to: • -Viewing geometry • -Terrain pressure and reflectivity • -Shape of NO2 vertical profile • -Clouds and aerosols • Pandora slant column determine from direct spectral fitting with ΩV = ΩS / secant[SZA] Troposphere Absorption, Scattering and Transmission through a cloud Absorption and Scattering by aerosols and molecules In-situ “True” NO2 and HCHO analyzers Tropospheric Vertical NO2 Column Mixed Layer Height (measured by ceilometer) plus surface NO2 can help provide a constraint on height of NO2 profile with assumed vertical shape Pandora UV/VIS Spectrometer Absorption and Scattering by the surface Ceilometer

20. Summary *PAMS locations BEHR TropNO2 Column May-July, 2015-2016 Ceilometer Aerosol layer / mixing height measurement Ground-based spectrometer Column density O3, NO2, HCHO, SO2 Improved trace-gas measurements • PAMS-EMP/Pandora effort: • Column measurements to support an improved assessment of emissions, chemistry, and dynamical processes driving ozone issue via daytime diurnal profiles of NO2/HCHO in conjunction with other measurement suite - consistent with the regulatory intent of the PAMS • Satellite validation TROPOMI & TEMPO – drawing a better connection on use/value and engages local AQ agencies. • Provides a sustainable low cost approach that mutually increases the value of measurement suite at these sites.