Acetone

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On this page we describe the acetone sources and sinks in GEOS-Chem.

Overview

Original formulation

The original formulation for acetone emission and deposition in GEOS-Chem is described in Jacob et al (2002).

Updates

This update was tested in the 1-month benchmark simulation v9-01-03b and approved on 14 Dec 2011.

NOTE: As of v10i, the 'DRYD-FLX' diagnostic still outputs Acetone in units of AtomsC/m2/s rather than Molecules/m2/s, regardless of what the units attached to the diagnostic say. --Jared Brewer (talk) 17:21, 2 July 2015 (UTC)

Emily Fischer has updated the acetone formulation used in GEOS-Chem.

Emily Fischer wrote:

  1. I Implemented a constant concentration of acetone in the ocean mixed layer of 15 nM, and applied the standard two-film model described by Liss and Slater [1974]. The flux is calculated using an updated Henry’s law coefficient and transfer velocities have been updated following Johnson [2010]. The model now reproduces aircraft measurements over the remote oceans well.

  2. Direct biogenic emissions of acetone from metabolism and decay are now calculated using the MEGAN biogenic emission model [Guenther et al., 2006]. The code assumes fraction of emissions that are light-independent is 0.20, and the temperature response factor (β) is 0.10 as recommended by Alex Guenther. The dependency on GEIA has been removed.

  3. The RETRO emission inventory for anthropogenic emissions of acetone and the isoalkanes has been implemented in my version of the code. I have also compared the chemical production of acetone in GEOS-Chem to the model used in Pozzer et al. [2010].

  4. There is currently no acetone dry deposition in the standard model (GEOS-Chem v9-01-01). I re-implemented deposition as described by Jacob et al. [2002] assuming a dry deposition velocity of 0.1 cm s-1 for ice-free land.

  5. Unrealistically high anthropogenic emissions over Botswana have been fixed by applying the CO-AnnualScalar.geos.1x1 file from D. Millet.

NOTE: Updates #3 (RETRO) and #5 (fix for anthro emissions over Botswana) have already been added to GEOS-Chem v9-01-02.

--Bob Y. 17:08, 14 December 2011 (EST)

Incorporation into standard code

Emily Fischer wrote:

I have run 1.5 year simulations at both 4° x 5° and 2° x 2.5° resolution. Both produce similar acetone global budgets.
Clean Up: I have removed code that I am sure is obsolete from acetone_mod.f. However, there is still some code that could be cleaned up in other modules. Here are my notes on what should be done when the new acetone budget is merged with the rest of the code.
  1. Acetone Diagnostic Menu Clean Up (ND11): The Direct Emissions diagnostic (ACETbg) is set to calculate all biogenic emissions. This includes dry leaf matter/dead plants and grasses. Thus, these two diagnostics in the acetone production and loss menu (ACETdl and ACETgr) can be removed. I have set them to zero in acetone_mod.f and added notes there.
  2. I believe that the following sub-routines can also be removed from acetone_mod.f: READ_JO1D and READ_RESP. They are no longer used within acetone_mod.f, but I am not sure if they are used in other parts of the code. They are called from emissdr.f, but only in reference to the acetone emissions. If they are not used elsewhere in the code, they can also be removed.

--Bob Y. 13:44, 10 August 2011 (EDT)

Previous issues that have been resolved

DRYACET is missing from globchem.dat

This update was tested in the 1-month benchmark simulation v9-02l and approved on 26 Jun 2013.

Emily Fischer discovered that the DRYACET species is missing from globchem.dat in GEOS-Chem v9-01-03. The addition of this species should have been included in the updated acetone chemistry. To include dry deposition of acetone, the following lines need to be added to globchem.dat:

A DRYACET            1.00 0.000E+00 0.000E+00 0.000E+00 0.000E+00
                    0   0   0   0   0   0   0   0   0
      ACET          +                                                     
=1.000DRYDEP        +1.000DRYACET       +                   +             
+                   +                   +                   +             
+                   +                   +                   +             
+                   +                   +                   +

--Melissa Payer 16:09, 29 May 2013 (EDT)

References

  1. Guenther, A., Karl, T., Harley, P., Wiedinmyer, C., Palmer, P.I., and Geron, C.: Estimates of global terrestrial isoprene emissions using MEGAN (Model of Emissions of Gases and Aerosols from Nature), Atmos. Chem. Phys., 6, 3181-3210, 2006.
  2. Jacob, D.J., B.D. Field, E. Jin, I. Bey, Q.B. Li, J.A. Logan, and R.M. Yantosca, Atmospheric budget of acetone, J. Geophys. Res., 107(D11), 4100, 10.1029/2001JD000694, 2002. PDF
  3. Johnson, M. T., A numerical scheme to calculate temperature and salinity dependent air-water transfer velocities for any gas, Ocean Sci., 6(4), 913-932, 2010
  4. Liss, P. S., and P. G. Slater, Flux of gases across the air-sea interface, Nature, 247, 181–184, 1974.
  5. Pozzer, A., J. Pollmann, D. Taraborrelli, P. Jöckel, D. Helmig, P. Tans, J. Hueber, and J. Lelieveld (2010), Observed and simulated global distribution and budget of atmospheric C2-C5 alkanes, Atmos. Chem. Phys., 10(9), 4403-4422., 2010

--Bob Y. 13:53, 10 August 2011 (EDT)