1. Relationships and Trends among Satellite NO 2 Columns, NO x Emissions, and Air Quality in North America Tiger Team Update David Streets, Greg Carmichael, Dan Cohan, Ben de Foy, Bryan Duncan, Arlene Fiore, Tracey Holloway, and Zifeng Lu Presented at AQAST 9 Meeting Saint Louis University, St. Louis, MO Jun 2-4, 2015

2. Reprise of the TT Concept 2 wildfires cities soil power plants transport Stratosphere/ background NO 2 columns, measured and modeled

3. Primary thrust for late 2014 to early 2015 Complete OMI processing, set up CMAQ model zero-out runs for the entire U.S. and sort the NO 2 columns into source-dominant categories; then begin to compare NO 2 column amounts in each category with source-based emission estimates. citiestransport corridors soil power plants wildfires background 3

4. U.S. Anthropogenic Exploring the potential for separating background contributions and source signatures in summertime NO 2 columns (Fiore/Valin)  Summer E US largely reflects anthropogenic sources  Summer SE US ~20-40% lightning  Summer NW US ~30-40% soil N. Am. Background Fraction of trop. NO 2 column in Base Simulation Soil Lightning 4 See Arlene Fiore’s presentation on Wednesday, 11:30 am

5. Soil NO Flux = A’(Biome, Soil Nitrogen) x f(T) x g(θ) x Pulse(Dry Period) x Canopy Reduction (Hudman et al., 2012) We are incorporating the current BDSNP scheme for soil NO x as implemented in CMAQ (Version 5.0.2) (Cohan) Potter or EPIC Fertilizer N pool data See Dan Cohan’s presentation on Wednesday, 11:15 am 5

6. Processing of NO 2 columns completed: example here of weekdays vs. weekends (Lamsal/Lu) 6 20052011

7. Further progress in emissions estimation from satellite retrievals US urban NO x emissions Emissions of nitrogen oxides from US urban areas: estimation from Ozone Monitoring Instrument retrievals for 2005−2014 Zifeng Lu, David G. Streets, Benjamin de Foy, Lok N. Lamsal, Bryan N. Duncan, Jia Xing Published in Atmospheric Chemistry and Physics Discussions, 15, 14,961-15,003, 2015 Update of OMI SO 2 observations over Indian coal-fired power plants Aura OMI observations of regional SO 2 and NO 2 pollution changes from 2005 to 2014 Led by Nickolay A. Krotkov In preparation, to be submitted to Atmospheric Chemistry and Physics US power plant NO x emissions Estimates of power plant NO x emissions and lifetimes from OMI NO 2 satellite retrievals Benjamin de Foy, Zifeng Lu, David G. Streets, Lok N. Lamsal, Bryan N. Duncan Accepted by Atmospheric Environment, in press USEPA AQS NO 2 vs. OMI NO 2 U.S. NO 2 trends (2005–2013): EPA Air Quality System (AQS) data versus improved observations from the Ozone Monitoring Instrument (OMI) Lok N. Lamsal, Bryan N. Duncan, Yasuko Yoshida, Nickolay A. Krotkov, Kenneth E. Pickering, David G. Streets, Zifeng Lu Published in Atmospheric Environment, 110, 130-143, 2015 7

8. How do trends and variations in AQS NO 2 relate to OMI NO 2 ? A)Publication Lamsal et al., U.S. NO 2 trends (2005–2013): EPA Air Quality System (AQS) data versus improved observations from the Ozone Monitoring Instrument (OMI), Atmospheric Environment, 110, 130-143, 2015. B) Website Website showing OMI NO 2 trends and variations over 20 US metropolitan areas and 150 power plants. Data + ready-made graphics for download by AQ managers. See Bryan Duncan’s presentation on Tuesday, 10:15 am 8

9. Annual trends and recession impacts in OMI NO 2 (de Foy) Cluster 1 (Blue) shows areas with constant emissions except for a large drop during the recession (lowest values: 2009,10,11). Cluster 2 (Green) shows mainly areas in the developed world with decreasing columns and a drop during the recession. Cluster 3 (Red) is in growth areas, showing a much smaller impact of the recession. Cluster 4 (Beige) is between Cluster 1 and 2. See Ben de Foy’s presentation on Wednesday, 10:45 am 9

10. NO x emissions from U.S. urban areas: estimation from OMI retrievals for 2005−2014 (Lu/de Foy) Use an exponentially-modified Gaussian (EMG) method and take into account the effect of wind on observed NO 2 distributions Estimate 3-year moving-average emissions of summertime NO x from 35 U.S. urban areas from OMI NO 2 retrievals during 2005−2014 10 OMI-derived NO x emissions are highly correlated (R>0.93) with weak-wind (<3 m/s) OMI NO 2 burdens as well as bottom-up NO x emission estimates

11. NO x emissions from U.S. urban areas: estimation from OMI retrievals for 2005−2014 (continued) From 2005 to 2014 over all 35 urban areas – total OMI-derived NO x emissions decreased by 49% – total bottom-up NO x emissions decreased by 43% – total weak-wind OMI NO 2 burdens decreased by 49% – averaged NO 2 concentrations decreased by 44% Pair-wise trends comparison among the above four NO x -related quantities for all 35 urban areas – high correlations are found for all urban areas (median R=0.8), particularly large ones (R up to 0.97) 11

12. Update of SO 2 emissions from Indian coal-fired power plants (2013-2014) (Lu) We have shown that SO 2 emissions, surface concentrations, and OMI observations over Indian coal-fired power plants increased by 60–70% during 2005–2012 Lu et al., EST, 2013 In years 2013 and 2014, 61 new coal- fired units were built – 39 units with capacity >500MW Power generation increased by – 19% since 2012 91% since 2005 Coal consumption increased by – 18% since 2012 95% since 2005 SO 2 emissions increased by – 19% since 2012 103% since 2005 12

13. Update of OMI SO 2 observations over Indian coal-fired power plants (2013 and 2014) (Krotkov/Lu) OMI SO 2 observations (new retrievals by N.A. Krotkov) Industrial region near Chhattisgarh (region indicated above) – the most active area in building new coal-fired power plants in India – 24 GW out of the total capacity of 28 GW in this area was installed after 2005 – ~26% of total newly-installed capacity in India from 2005 to 2014 – OMI SO 2 columns125%±50% increase – total SO 2 emissions158% increase 13 Thanks! More on analysis of the zero-out CMAQ runs next time!