README -- Describes contents of HEMCO/NEI2011/v2017-02-MM directory 27 Feb 2017 GEOS-Chem Support Team (geos-chem-support@g.harvard.edu) and Katherine Travis (ktravis@fas,harvard.edu ) Overview: =============================================================================== In this folder are monthly-mean NEI2011 data. These data were created from the hourly NEI2011 data (prepared by Katherine Travis, ktravis@fas.harvard.edu) from the ../v2015-03 folder. Folders and files =============================================================================== 01/, 02/, .. 12/ Data folders that contain monthly-mean NEI2011 data files for each month of the year. The files cover several emission categories: Monthly mean ... NEI11_0.1x0.1_2011MM_monmean.nc : Surface inventory NEI11_0.1x0.1_2011MM_monmean_ag.nc : Agriculture NEI11_0.1x0.1_2011MM_monmean_c3marine.nc : Ships NEI11_0.1x0.1_2011MM_monmean_egu.nc : Electric generating units NEI11_0.1x0.1_2011MM_monmean_egupk.nc : Peaking EGU's NEI11_0.1x0.1_2011MM_monmean_oilgas.nc : Oil and gas sector NEI11_0.1x0.1_2011MM_monmean_onroad_catx.nc : Onroad w/ CA, TX emissions NEI11_0.1x0.1_2011MM_monmean_othpt.nc : Other point sources NEI11_0.1x0.1_2011MM_monmean_ptnonipm.nc : Non-EGU industrial stacks where MM = 01, 02, .. 12 Horizontal resolution : 0.1 deg lon x 0.1 deg lat # of longitudes : 900 # of latitudes : 400 # of levels : 1 # of times : 1 (time-average of entire month) netCDF compression : Level 1 (nccopy -d1) ############################################################################### ##### NOTE: The netCDF file attribute 'lev:positive = "up"' was added ##### ##### to all files in NEI2011/v2017-02-MM having a vertical dimension. ##### ##### This was done to facilitate reading these files with GCHP. ##### ##### -- Bob Yantosca (27 Feb 2017) ##### ############################################################################### scripts/ Shell scripts (written in bash) that were used to create the monthly-mean NEI2011 data files. We preserve them here for reference. These are: NEI2011_monthly_mean.sh Uses CDO utilities to create monthly mean data files from the hourly data files stored in ../v2015-03. NEI2011_fix_time.sh Uses the NCO ncap2 utility to make sure that the time value is 0 and the time string is e.g. "hours since 2011-01-01 00:00:00" (NOTE: You have to manually edit the month in that string). Then also compresses the monthly mean files (listed above) using netCDF level 1 compression to obtain a big reduction in file size. ############################################################################### ##### ORIGINAL README FOLLOWS BELOW ##### ##### DESCRIBING THE HOURLY NEI2011 DATA ##### ############################################################################### Data are provided on a 0.1x0.1km rectilinear grid. Acknowledgment: --------------- We acknowledge the U.S. Environmental Protection Agency for providing 2011 North American emission inventories. These emission inventories are intended for research purposes and were developed using information from the 2011-based modeling platform version 1 http://www.epa.gov/ttnchie1/net/2011inventory.html as a starting point. A technical document describing the 2011v1 modeling platform can be found here: http://www.epa.gov/ttn/chief/net/2011nei/2011_nei_tsdv1_draft2_june2014.pdf Emissions were provided to us by George Pouliot: George Pouliot Physical Scientist Emissions and Model Evaluation Branch Atmospheric Modeling and Analysis Division/NERL/ORD Mail Drop E243-04 Research Triangle Park, North Carolina VOICE: (919) 541-5475 FAX: (919) 541-1379 pouliot.george@epa.gov About the NEI2011 data: =============================================================================== Emissions are distributed on up to 6-levels depending on the stack heights of the original data. Each file contains emissions for one day, at hourly resolution. There are 7 separate files that make a complete inventory for one day: 1. Surface inventory 2. othpt = other point sources 3. ptnonipm = non-EGU industrial stacks 4. c3marine = ships 5. egu = electric generating units (EGUs) 6. egupk = peaking electric generating units (EGUs) 7. oilgas = oil and gas sector (new to NEI2011) Files: ------------------------------------------------------------------------------- Example set of files for August 2011: NEI11_0.1x0.1_20110801.nc # surface inventory NEI11_0.1x0.1_20110801_c3marine.nc # ships NEI11_0.1x0.1_20110801_egu.nc # Electric-generating units (EGU's) NEI11_0.1x0.1_20110801_egupk.nc # Peaking EGU's NEI11_0.1x0.1_20110801_oilgas.nc # oil & gas sector NEI11_0.1x0.1_20110801_othpt.nc # other point sources NEI11_0.1x0.1_20110801_ptnonipm.nc # Non-EGU industrial stacks -- For all files: Resoluton : 0.1 x 0.1 grid Units : kg/m2/s Timestamps : Hourly for each day Compression : Level 5 (e.g. nccopy -d5) ############################################################################### ##### NOTE: The mask file for use with NEI2011 is stored in the ##### ##### HEMCO/MASKS/v2014-07 directory: ##### ############################################################################### HEMCO/MASKS/v2014-07/USA_LANDMASK_NEI2011_0.1x0.1.nc -- Mask file for use with the NEI2011 emissions. Resoluton : 0.1 x 0.1 grid Units : kg/m2/s Timestamps : Hourly for each day Compression : Level 1 (e.g. nccopy -d1) Additional considerations: ------------------------------------------------------------------------------ 1. Emissions from NEI11 include some emissions over Canada and Mexico. We leave it as a research decision whether to use NEI11 or the CAC/BRAVO inventories over these areas. 2. In addition, NEI11 includes ship emissions over water out to a certain distance from land. This may lead to some double-counting with the PARANOX scheme. 3. Finally, NEI11 includes emissions from aircraft at the airports, which may also be double-counted with the AEIC emissions. 4. We do not take the above issues into account at this time, although masks may be developed to resolve double-counting issues. List of species: ------------------------------------------------------------------------------- Emission species are mapped from the CBO5 mechanism to the GEOS-Chem chemical mechanism. The CBO5 names are preserved in the file, with each species that has a GEOS-Chem equivalent given an NEI11 named attribute. For example, FORM is the CBO5 name, which is CH2O in GEOS-Chem. Units of all species are in kg/m2/s. Species included are: CO, NO, NO2, HNO2, NH3, CH2O, RCHO, MACR, ACET, ALK4, PRPE, EOH, MOH, XYLE, TOLU, BENZ, SO2, SO4, C2H4, C2H6, C3H8, ALD2, BC, OC I map PAR into ALK4, ACET, C3H8, and MEK using the following method: I used the graph of the top 50 VOCs from the following paper: http://www.epa.gov/ttnchie1/software/speciate/atmospheric.pdf, and determined the PAR weighting from the following report: http://www.camx.com/publ/pdfs/cb05_final_report_120805.pdf. I then determined the fraction by carbon of PAR for each of the following species. Note that it will not add to 100% since some species are double ounted (benzene). ACET = PAR * 0.06 C3H8 = PAR * 0.03 MEK = PAR * 0.02 ALK4 = PAR * 0.87 In addition, PRPE = 0.5 OLE + 0.5 IOLE About the scaling factors used with the data: =============================================================================== NEI11 may be used with annual scaling factors based on EPA’s national inventory. For NEI11, these were calculated to be as follows using EPA's National Tier1 CAPS (http://www.epa.gov/ttnchie1/trends/) IF ( THISYEAR .eq. 2012 ) THEN ! scale based on 2011 NEI11v1 ScCO = 0.981 ScNOx = 0.940 ScPM10 = 0.999 ScPM25 = 0.995 ScSO2 = 0.802 ScVOC = 0.986 ScNH3 = 0.999 ELSE IF ( THISYEAR .ge. 2013 ) THEN ScCO = 0.962 ScNOx = 0.899 ScPM10 = 0.998 ScPM25 = 0.991 ScSO2 = 0.785 ScVOC = 0.971 ScNH3 = 0.998 ENDIF Traffic Scaling: ------------------------------------------------------------------------------ There is evidence that vehicle emissions of NOx and CO may be overestimated (Anderson et al, 2014(Atmospheric Environment) ; Brioude et al, 2013 (Atmospheric Chemistry and Physics) ; Yu et al, 2012 (Atmospheric Pollution Research); Fujita et al, 2012 (Journal of the Air and Waste Management Association)). We provide onroad and offroad vehicle emissions separate from the complete inventory in the following folders: /NEI11/onroad** /NEI11/offroad **The onroad inventory includes files called *onroad_catx.nc. Since California and Texas provided more detailed onroad inventories to the EPA, those emissions are separated out from the rest of the onroad inventory. Thus the *onroad.nc files have zero emissions over California and Texas. The option is available to remove a fraction of NO, NO2, HONO, and CO emissions from these inventories. The default setting will be to remove zero emissions. If you set the NOx option to 0.8, you would remove 0.8 of the onroad and off road emissions as follows: NO from ‘NEI11_0.1x0.1_20110801_onroad.nc’ , ‘NEI11_0.1x0.1_20110801_onroad_catx.nc’ and 'NEI11_0.1x0.1_20110801_nonroad.nc’ would be multiplied by 0.2 and removed from NO in ‘NEI11_0.1x0.1_20110801.nc’. This would also apply to NO2 and HONO.