README -- Describes contents of HEMCO/PARANOX/v2015-02 17 Feb 2015 GEOS-Chem Support Team geos-chem-support@g.harvard.edu Overview: =============================================================================== This directory contains the look up tables (LUT's) used by the PARANOX ship plume model. These files were originally created by Chris Holmes and Geert Vinken (see original README below). Christoph Keller has migrated these data files to netCDF file format as well as ASCII text file format. You can pick which version to use in the HEMCO Configuration file. For example, if you are using HEMCO in an ESMF/MPI environment, you may need to read the text files because the ESMF envrionment may not be able to read a 7-dimensional look up table from netCDF format. Files: =============================================================================== COARDS-compliant netCDF format: ------------------------------------------------------------------------------- ship_plume_lut_02ms.nc : PARANOX look-up tables, wind speed = 2 m/s ship_plume_lut_06ms.nc : PARANOX look-up tables, wind speed = 6 m/s ship_plume_lut_10ms.nc : PARANOX look-up tables, wind speed = 10 m/s ship_plume_lut_14ms.nc : PARANOX look-up tables, wind speed = 14 m/s ship_plume_lut_18ms.nc : PARANOX look-up tables, wind speed = 18 m/s Text format: ------------------------------------------------------------------------------- ship_plume_lut_02ms.txt : PARANOX look-up tables, wind speed = 2 m/s ship_plume_lut_06ms.txt : PARANOX look-up tables, wind speed = 6 m/s ship_plume_lut_10ms.txt : PARANOX look-up tables, wind speed = 10 m/s ship_plume_lut_14ms.txt : PARANOX look-up tables, wind speed = 14 m/s ship_plume_lut_18ms.txt : PARANOX look-up tables, wind speed = 18 m/s Both the netCDF and text files contain these data fields: T : Temperature [K] JNO2 : J-value (integrated intensity) for NO2 [s-1] O3 : O3 ambient mixing ratio [nmol mol-1] SEAO : Solar elevation angle at emission time [degrees] SEA5 : Solar elevation angle after 5 hours [degrees] Jratio : Ratio of J(OH) / J(NO2) NOx : Ambient NOx mixing ratio [pmol mol-1] FNOx : Fraction of ship NOx remaining as NOx after 5 hours [mol mol-1] DNOx : Fraction of ship NOx deposited after 5 hours [mol mol-1] OPE : Net O3 production efficiency integrated over 5h [mol(O3) mol(HNO3)-1] MOE : CH4 oxidation efficiency integrated over 5h [mol(CH4) mol(NOX)-1] Notes from Christoph Keller (17 Feb 2015) ============================================================================== (1) I took the netCDF files just as Chris Holmes gave them to us. I also kept the original netCDF reading routines in hcox_paranox_mod.F90 since HEMCO cannot handle 7D fields. For use in ESMF, I wrote a little wrapper script (WRITE_LUT_TXTFILE) that dumps all input data into a txt-file. I then just ran one 1-hour simulation with the WRITE_LUT_TXTFILE calls in hcox_paranox_mod.F90 uncommented to create all the txt-files. The input data format for PARANOx can be set in the HEMCO_configuration file: 102 ParaNOx : on NO/NO2/O3/HNO3 --> LUT data format : nc --> LUT source dir : $ROOT/PARANOX/v2015-02/ If you set LUT data format to txt, PARANOx will try to read files ship_plume_lut_??ms.txt in the specified LUT source dir. Otherwise, it will read the netCDF files (ship_plume_lut_??ms.nc) in that same directory. (2) #### IMPORTANT #### One thing to keep in mind is that no NO ship emissions will be emitted if PARANOx is turned off, e.g. if you set the PARANOx toggle to off in the HEMCO configuration file, no ship NO will be released at all even if other ship emissions (e.g. SO2) are still enabled. You’d have to change the ExtNr for entries ICOADS_SHIP_NO and EMEP_SHIP_NO from 102 to 0 if you wanted to release ship NO without NOx in-plume reduction. ############################################################################### ##### ORIGINAL README FOLLOWS HERE ##### ############################################################################### README 16 Jun 2014 Original message from Chris Holmes: =============================================================================== Hello GCST, Geert and I have updated the ship plume emissions in GEOS-Chem. A paper based on the updated model is now accepted in ACP (http://www.atmos-chem-phys-discuss.net/14/3427/2014/acpd-14-3427-2014.html). I am writing to pass along the updates to you for inclusion in the GC standard code. I have posted a patch file and new look-up tales that accompany this code update at ftp://halo.ess.uci.edu/Public/holmes/shipnox_v9-02/ The patch will apply to the git commit tagged as "v9-02-Public-Release" on 2014-2-27. After applying the patch, you will need to update the "101 FORMAT" statement to point to the correct data directory on your system. The updated features are as follows: 1. Ship plume chemical aging now depends on wind speed, which directly affects the plume dispersion rates and indirectly affects the plume chemistry. 2. The underlying Gaussian plume model now includes dry deposition. 3. NO, NO2, and O3 are all emitted separately, consistent with removing the NOx and Ox families in GC v9-02. 4. The look-up tables are now in netCDF format. 5. CH4 oxidation in ship plumes is now diagnosed and written in the paranox_ts files. This is only a diagnostic and does not affect the model chemistry. As with previous versions, paranox_mod.F uses a look-up table derived from a Gaussian plume model to provide effective emission factors for NOx, O3, and HNO3 from ships. Both the Gaussian plume model and GEOS-Chem with the embedded look-up tables have been evaluated against observations (Holmes et al. 2014; Vinken et al., 2011). The emission factors are based on 8 environmental variables from the CTM: ambient concentrations of NOx and O3, solar zenith angle at emission time and 5 hours later, photolysis rates of NO2 and O3, temperature, and wind speed. Let me know if you have any questions about these changes. Thanks, Chris Message from Chris Holmes (7/16/14): =============================================================================== Tomas Sherwen reported high values of O3 dry deposition over Shanghai, northern Europe, and near Lake Superior. Hello all, I have a solution. The attached patch file applies to v9-02-Public-Release with the parent commit "Clean up use of State_Met in several modules". This supersedes and replaces my previous patch file that is currently posted on the wiki here: http://wiki.seas.harvard.edu/geos-chem/index.php/Ship_emissions#In_GEOS-Chem_v10-01_and_newer_versions The wiki description of my changes since v9-02 is still accurate. The substantive difference between this patch and the previous one is that when O3 is lost in sub-grid-scale ship plumes, the loss is calculated by the chemical solver using a 1st order rate coefficient from paranox. The problem that Tomas identified occurred because paranox calculates a 1st order loss rate for O3 in ship plumes by diving the flux by the ambient O3 concentration in a grid box. The 1st order loss rate can be quite high when the O3 concentration is low (divide by a small number). Tomas's problem occurs when the O3 concentration then increases after the paranox call and before the 1st order loss is applied, so that a large 1st order loss rate is applied to a large O3 concentration. Because of the timing and order of operations in GC, this can occur when using NLPBL mixing, but not with instant PBL mixing. With the plume O3 loss now calculated inside chemistry, the problem does not occur. My patch requires adding the following new reaction to globchem.dat A 998 0.00E+00 0.0E+00 0 0 S 0.00 0. 0. O3 + = + + + + + + + + + + + + + + + I have not used KPP and haven't updated the KPP files. Regards, Chris