Difference between revisions of "Mercury"

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== Diagnostics ==
 
== Diagnostics ==
  
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==== Notes ====
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=== Notes ===
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(1) Helen Amos is developing diagnostics for reactive gaseous mercury and reactive particulate mercury.
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#Helen Amos is developing diagnostics for reactive gaseous mercury and reactive particulate mercury.
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<br>(2) Bess Corbitt is developing diagnostics for a tagged-tracer simulation with 17 world regions. For example, when running with this option, for prompt recycling of deposited mercury, instead of HG-SRCE category and Hg0_ln tracer name for the total tracer, I would have category HG0-RECY and tracername Hg0_usa, Hg0_can, etc.
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#Bess Corbitt is developing diagnostics for a tagged-tracer simulation with 17 world regions. For example, when running with this option, for prompt recycling of deposited mercury, instead of HG-SRCE category and Hg0_ln tracer name for the total tracer, I would have category HG0-RECY and tracername Hg0_usa, Hg0_can, etc.
  
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==== Previous discussions ====
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=== Previous discussions ===
  
 
Here are some suggested changes:
 
Here are some suggested changes:

Revision as of 19:05, 22 September 2010

Hello Team-Hg

Code

Previous discussions (6/2008)

  1. Standardize the solver. Everyone should use the solver Chris developed for the Hg chemistry
    (located at ~cdh/GC/RevisedChem.v7-04-06/mercury_mod.f)
    • outstanding issue - dry dep of Hg0* <- currently working on this (eds)
    • See GEOS-Chem v8-03-02 and later for Holmes et al. 2010 Hg+Br simulation.
  2. Catalog all emissions options and develop clear flagging system to choose your own adventure. This will include:
    • different anthropogenic emissions scenarios/corrections (i.e Jaffe vs. Streets) <- going to work on the anthro emissions soon (eds),
    • different land emissions. <- nvd will work on this
    • Logicals implemented to select anthropogenic emissions from GEIA 2000, GEIA 2005, or GEIA scaled to Streets et al. 2006 regional totals.
  3. Diagnostics. See separate section below.
    • Diagnostics have been updated.
  4. Comment everything in the code. Remove old bits of code that are hanging around & commented out.
    • Ongoing.
  5. GEOS-5
    • This is the standard meteorology to use at present. MERRA is in development.
  6. Get the land stuff out of ocean_mercury_mod.f and into it's own module <- nvd will work on this
    • Implemented by ccarouge v8-03-02.

Chemistry 'issues'

Previous discussions

  1. Oxidant.
    • Chris has a simulation with Hg-Br chemistry and SS aerosol deposition; the global budget is ok, but the Br concentrations in the BL are too low to generate diurnal cycles. (cdh working on it)
  2. Snow/ice scavenging of HgII
  3. Dry deposition of "aqueous HgII.
    • (Explanation from Chris: We calculate the fraction of HgII, Fg, which is gas phase. But we're currently applying the dry deposition velocity to both gas and aqueous fractions. I think it would be better to deposit the aqueous fraction at the velocity of HgP; this would be slower dep, but I don't know how much. This is definitely up for discussion.)
    • See Holmes et al. 2010 for discussion of chemistry in standard version.

Diagnostics

Notes

  1. Helen Amos is developing diagnostics for reactive gaseous mercury and reactive particulate mercury.
  2. Bess Corbitt is developing diagnostics for a tagged-tracer simulation with 17 world regions. For example, when running with this option, for prompt recycling of deposited mercury, instead of HG-SRCE category and Hg0_ln tracer name for the total tracer, I would have category HG0-RECY and tracername Hg0_usa, Hg0_can, etc.

Previous discussions

Here are some suggested changes:

  1. Emissions should have units 'kg/m2/s' or something of the form 'mass/area/time' (they are currently 'kg'). The HG-SRCE diagnostic currently has all of the Ocean tracers and fluxes; these should go elsewhere.
  2. The Ocean Hg0, Hg2, HgC should have concentration units not kg. Is 'molar' the best choice? Fluxes of these should be in concentration/time, not kg.
  3. The ocean restart files should have concentration units not kg. They currently use the category 'OCEAN-HG' which would make sense for the ND03 ocean Hg0, Hg2, HgC output too.
  4. 'PL-HG2-$' doesn't really describe all of the fluxes in our model. There are a lot of diagnostic quantities which are either chemical P/L fluxes or rate constants. I think these should all be in one diagnostic called something like 'PL-HG-$' (or maybe 'PL-HG-A', 'PL-HG-O' to separate the atmosphere and ocean). The fluxes in this diagnostic would include redox in air and water, colloidal sinking, ocean-atmosphere piston velocity, ...

Here are the current GEOS-Chem Hg outputs 

      CATEGORY ILUN TRCNAME   TRC         UNIT      TAU0(DATE)       DIMENSIONS
  1 : IJ-AVG-$   23     Hg0     1         pptv 157776.00(2003010100)  72 46 30
  2 : IJ-AVG-$   23     Hg2     2         pptv 157776.00(2003010100)  72 46 30
  3 : IJ-AVG-$   23     HgP     3         pptv 157776.00(2003010100)  72 46 30
  4 : WETDCV-$   23     Hg2  3002         kg/s 157776.00(2003010100)  72 46 30
  5 : WETDCV-$   23     HgP  3003         kg/s 157776.00(2003010100)  72 46 30
  6 : WETDLS-$   23     Hg2  3002         kg/s 157776.00(2003010100)  72 46 30
  7 : WETDLS-$   23     HgP  3003         kg/s 157776.00(2003010100)  72 46 30
  8 :  HG-SRCE   23  Hg0_an 34001           kg 157776.00(2003010100)  72 46  1
  9 :  HG-SRCE   23  Hg0_aq 34002           kg 157776.00(2003010100)  72 46  1
 10 :  HG-SRCE   23  Hg0_oc 34003           kg 157776.00(2003010100)  72 46  1
 11 :  HG-SRCE   23  Hg0_ln 34004           kg 157776.00(2003010100)  72 46  1
 12 :  HG-SRCE   23  Hg0_na 34005           kg 157776.00(2003010100)  72 46  1
 13 :  HG-SRCE   23  Hg2_an 34006           kg 157776.00(2003010100)  72 46  1
 14 :  HG-SRCE   23  Hg2_aq 34007           kg 157776.00(2003010100)  72 46  1
 15 :  HG-SRCE   23  Hg2_sk 34008           kg 157776.00(2003010100)  72 46  1
 16 :  HG-SRCE   23  HgP_an 34009           kg 157776.00(2003010100)  72 46  1
 17 :  HG-SRCE   23    KwHg 34010         cm/h 157776.00(2003010100)  72 46  1
 18 :  HG-SRCE   23     HgC 34011           kg 157776.00(2003010100)  72 46  1
 19 :  HG-SRCE   23 Hg_to_C 34012           kg 157776.00(2003010100)  72 46  1
 20 : PL-HG2-$   23 Hg2_Hg0 35001           kg 157776.00(2003010100)  72 46 30
 21 : PL-HG2-$   23  Hg2_OH 35002           kg 157776.00(2003010100)  72 46 30
 22 : PL-HG2-$   23  Hg2_O3 35003           kg 157776.00(2003010100)  72 46 30
 23 : PL-HG2-$   23  Hg2_SS 35004           kg 157776.00(2003010100)  72 46  1
 24 : PL-HG2-$   23 Hg2_SSR 35005           /s 157776.00(2003010100)  72 46  1
 25 : DRYD-FLX   23   Hg0df 36001  molec/cm2/s 157776.00(2003010100)  72 46  1
 26 : DRYD-FLX   23   Hg2df 36002  molec/cm2/s 157776.00(2003010100)  72 46  1
 27 : DRYD-FLX   23   HgPdf 36003  molec/cm2/s 157776.00(2003010100)  72 46  1
 28 : DRYD-VEL   23   Hg2dv 37002         cm/s 157776.00(2003010100)  72 46  1
 29 : DRYD-VEL   23   HgPdv 37003         cm/s 157776.00(2003010100)  72 46  1

I think we should change lines 8-24 (I've kept the same line numbers and TRCNAME, but changed CATEGORY, TRC, or UNIT): 

      CATEGORY  TRCNAME    TRC         UNIT 
  8 :  HG-SRCE   Hg0_an  34001      kg/m2/s 
 10 :  HG-SRCE   Hg0_oc  34002      kg/m2/s 
 11 :  HG-SRCE   Hg0_ln  34003      kg/m2/s 
 12 :  HG-SRCE   Hg0_na  34004      kg/m2/s 
 13 :  HG-SRCE   Hg2_an  34005      kg/m2/s
 16 :  HG-SRCE   HgP_an  34006      kg/m2/s 
  9 : OCEAN-HG   Hg0_aq  xxxx1        mol/L 
 14 : OCEAN-HG   Hg2_aq  xxxx2        mol/L 
 18 : OCEAN-HG   HgC     xxxx3        mol/L 
 20 :  PL-HG-A   Hg2_Hg0 35001      kg/m3/s 
 21 :  PL-HG-A   Hg2_OH  35002      kg/m3/s 
 22 :  PL-HG-A   Hg2_O3  35003      kg/m3/s 
 23 :  PL-HG-A   Hg2_SS  35004      kg/m3/s 
 24 :  PL-HG-A   Hg2_SSR 35005           /s
 15 :  PL-HG-O   Hg2_sk  xxxx1      kg/m3/s 
 19 :  PL-HG-O   Hg_to_C xxxx2      kg/m3/s
 17 :  PL-HG-O   KwHg    xxxx3         cm/h


The only thing I have to add is that at first I didn't realize that wet deposition of Hg(II) was composed of both WETDCV and WETDLS. Is it important to save those components out as 2 separate parts? (nvd) To answer Nicole, it is useful to have the large scale and convective wet scavenging written out separately for comparison to wet deposition observations. They are different processes in the model and can tell us different things about where the model is performing well and where it needs improvement (for example, convective scavenging over the Gulf Coast region). (eds)

GTMM

See the Global Terrestrial Mercury Model wiki page: http://wiki.seas.harvard.edu/geos-chem/index.php/Global_Terrestrial_Mercury_Model

User manual: http://www.geos-chem.org/doc/man/files/GTMM_manual_20100811.pdf

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