GEO-CAPE Emissions Working Group

1. GEO-CAPE Emissions Working Group • What are the benefits of geostationary (GEO) • measurements for constraining emissions and chemical processes? • Answer using pilot demonstrations of high resolution data from in-situ and remote sensing platforms, along with forward and inverse modeling analysis. • assess an expanded suite of topics in 2013 (AOD and HCHO) • target specific questions related to emissions, beyond accounting and beyond GEO lifetime • compare value added of GEO relative to LEO • utilize products from OSSE WGs

2. GEO-CAPE Emissions Working Group • Simulate and evaluate HCHO in LA Basin for CalNex 2010 • Explore sensitivity of LEO and GEO HCHO columns to different emissions inventories, including temporal variability • Parallel work using satellite and field observations of NO2 to constrain NOx emissions in California • Explore formation of other secondary species (O3, glyoxal) using modeling with field measurements and satellite data I. Constraining anthropogenic emissions with satellite observations of HCHO Si-Wan Kim, NOAA/CU CIRES Greg Frost, NOAA/CU CIRES Michael Trainer, NOAA Rokjin Park, Seoul National University

3. WRF-Chem: Sensitivity to Emission Inventories NO2 columns HCHO columns O3 (PBL) Glyoxal columns

4. GEO-CAPE Emissions Working Group II. Constraints on NO2 emissions and chemistry Sensor array on 2km grid for CO2, NO2, O3, … Nodes deployed on school rooftops Ron Cohen (UC Berkeley) a) Use measurements from BEACON to characterize subgrid scale variability of NO2, CO and other gases http://beacon.berkeley.edu/

5. Cohen-Emissions WG b) Use models and satellite observations to understand links between meteorology and NOx lifetime

6. GEO-CAPE Emissions Working Group III. Constraints on sector-specific emissions contributions to CH4 Kevin Wecht, Harvard Helen Worden, NCAR John Worden, JPL Nicolas Bousserez, Andre Perkins, Daven Henze CU Boulder Greg Frost, NOAA/CU CIRES Bob Chatfield, NASA AMES

7. OSSEs to evaluate the utility of GEO-CAPE methane observations for constraining North American emissions • Can we detect doubling of emissions from natural gas in the western US? • How do results compare to traditional LEO capabilities? Step 1: Perturb model natural gas emissions by 2x in west. Step 3: Assimilate pseudo-obs into GEOS-Chemadjoint inversion GEOS-Chem CTM Perturbed/prior emissions “Observed” enhancement GEOS-ChemAdjoint 1.0 2.0 -1.0 1.0 [ppb] Step 2: Sample model atmosphere with GEOCAPE obs. operator Emission error reduction achieved in OSSE Rows of GEOCAPE averaging kernel matrix GEOS-Chem CTM 200 0.1 hPa Pressure [hpa] • Both GEOCAPE and LEO capture N.A. emissions. • Only GEOCAPE locates emissions within the perturbed region. 954 hPa 1000 0.0 0.75

8. Address key questions using new inverse modeling diagnostics. • How many emissions have been constrained independently? • Degree Of Freedom for Signal (DOFs) • To what extent are different CH4 sources (e.g., natural vsOil&Gas) constrained independently from each other? • Averaging kernel (or resolution) matrix • Example for toy CO2 inversion using pseudo GOSAT data: Self-sensitivity ( ) 0 0.33 0.67 1.00 DOFs=48.6 GOSAT CO2 monthly observations (2009/07)

9. GEO-CAPE Emissions Working Group IV. Constraining aerosol sources with geostationary measurements Jun Wang (UNL) Daven Henze (CUB)

10. Constraining aerosol sources with geostationary measurements • radiances from TEMPO and GOES-R estimated for a variaty of different geostationary configurations (e.g., separating angle between the two instruments over North America) • Utilize atmospheric samples from the OSSE group’s WRF-Chem 4 km nature runs. • Aerosol WG activity:estimate the potential for constraining aerosol optical depth and possibly single scattering albedo. • Emissions WG activity: extended to consider the potential for these radiances to constrain emissionsusing GEOS-Chemadjoint model • Case studies targeting BC emissions from wildfires in the west during 2010/2011 will be targeted. • Ability to constrain aerosol and aerosol precursor emissions using satellite AOD demonstrated in case studies (Wang et al., 2013; Xu et al., submitted). • Global OSSE WG activity: extend to global scales, GEOS-5 nature run, constellation impacts.

11. GEO-CAPE Emissions Working Group V. Constraints from geostationary observations on NH3 fluxes and associated PM2.5 concentrations Karen Cady-Peirira (AER Inc.) Jesse Bash(US EPA), Juliet Zhu, Daven Henze(CU Boulder)

12. Constraints from geostationary observations on NH3 fluxes and associated PM2.5 concentrations Motivation • NH3can impact PM2.5 concentrations by regulating NH4NO3 • Elevated aerosol nitrate concentrations linked to treatment of NH3sources and sinks • NH3 sources projected to increase, rivaling NO2 as source of reactive nitrogen deposition in the coming decades • Progress hindered by uncertainty in NH3fluxes RCP 8.5 6 4.5 2.6 Nr tot NOy NHx US GEOS-Chem [µg/m3] CA measured [µg/m3] Walker et al., 2012 Fabien Paulot et al., in prep Paulot et al., 2012

13. Constraints from geostationary observations on NH3 fluxes and associated PM2.5 concentrations • Motivation • • NH3 can impact PM2.5 concentrations by regulating NH4NO3 • • Elevated aerosol nitrate concentrations linked to treatment of NH3 sources and sinks • • NH3 sources projected to increase, rivaling NO2 as source of reactive nitrogen deposition in the coming decades • • Progress hindered by uncertainty in NH3 fluxes • GEO-CAPE Working Group Activities for 2012 / 2013 • Bidirectional air-surface exchange, fertilizer emissions, and diurnal variability of livestock emissions updated in GEOS-Chem and CMAQ • Ensembles of model simulations run at 0.5 x 0.667 (GEOS-Chem) and 12 km (CMAQ) with different emissions process configuration. • Model fields sampled according to LEO and GEO strategies; pseudo retrievals derived using TES algorithm • Differences in pseudo observations show the potential for constraining NH3 emissions processes using GEO vsLEO remote sensing instruments.

14. 2013 WG: diurnal variability of NH3 emissions TES overpass time Current air quality models do not well represent the diurnal variability of livestock emissions (Jeong et al., submitted; Zhu et al., 2013). Existing NH3 monitoring networks (2 week average) or remote sensing observations (twice a day) are insufficient to characterize NH3 diurnal variability. Improved representation of NH3 diurnal variability impacts reactive nitrogen deposition and particulate formation. High bias in GEOS-Chem aerosol nitrate reduced by up to 1 ug/m3. Workplan: CMAQ and GEOS-Chem & pseudo NH3 GEO-CAPE observations to assess the potential for geostationary measurements to constrain models’ diurnal emissions schemes.

15. Topics for discussion • what can we use from the regional and global OSSE groups? • nature runs, averaging kernels • to what extent do we focus on constraints on emissions vs chemical processing, deposition, etc.? can we be the chemistry / emissions WG? • discovery about holes in models (e.g., VOC budget in SJ Valley) • can emissions WG findings help other WGs? What outputs are needed? • how do we adjust our activities to adapt to TEMPO / GCIRI future? • - does alignment / positioning / timing impact benefit of collocated measurements? • - CO / NOx, CO / VOC correlations, value high & contingent upon CO sensitivity • - what lasting knowledge will we have acquired regarding emissions (which are constantly changing) after the lifetime of GEO-CAPE instrument(s)? • Can we be the chemistry / emissions WG? • will we be prepared for inverse modeling capabilities at regional scale (4km) by 2020? • ???

16. Extra slides

17. Model NOx lifetime vs. wind speed. L Valin et al., GRL 2013

18. Riyadh Low water, less OH, more NO2 High water, more OH, less NO2 Valin and Cohen in prep

19. H2O lifetime longer shorter Valin and Cohen in prep

20. WRF-Chem NO2 columns Los Angeles Basin 14 LST Pasadena Fontana LAX Ontario Riverside Irvine NO2 columns (1015molec. cm-2)

21. WRF-Chem: Diurnal variations of NO2, HCHO, Glyoxal, and O3 NO2 columns HCHO columns O3 (PBL) Glyoxal columns

22. 2012 WG: will geostationary observations help constraint NH3 bidirectional fluxes? Geostationary retrievals of NH3 RVMR (ppb). Differences between each source model and base-case: - NH3 retrievals were sampled from a CMAQ 4km simulated atmosphere - “TES like” error characteristics and sensitivities (i.e., Ak) - Radiative transfer model with applied noise used to get radiances - June 9th at 13:00, prior to peak difference in modeled NO3- on June 10th Bidi - Base Bidi-F - Bidi Bidi-F - Base Conclusion: A geostationary instrument could quantify differences in NH3 concentrations due to changes in the processes governing NH3 deposition and evasion. Existing remote sensing capabilities can not likely discern such differences. (x) location of TES global survey observations

23. 2012 WG: impacts if bidi fluxes of NH3 sources on NO3- Corresponding aerosol NO3- with different treatments of NH3 sources: • Bidi: increased NO3 at CSN (10%) and IMPROVE (44%) sites • Bidi-F (+50% more fertilizer): increased NO3 at CSN (21%) and IMPROVE (19%) sites Comparison to observations:• All model cases underestimate NO3 concentrations • Biases were ~10% less at CSN sites and ~20% less at IMPROVE sites in bidi case Base Bidi Bidi-F 07/01 07/04 07/07 07/10 Conclusions CSN • Geostationary NH3 retrievals would be instrumental in testing and evaluating NH3 air-surface exchange algorithms and emissions inventories. • This would better inform policy makers’ assessments of current environmental conditions and identify mitigation strategies for: • Conditions leading to nitrate PM episodes • Excessive nutrient depositions