Difference between revisions of "CH4 simulation"

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This page contains information about the methane (CH4) simulation in GEOS-Chem.
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__FORCETOC__
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'''''[[Aerosol-only simulation|Previous]] | [[CO2 simulation|Next]] | [[Guide to GEOS-Chem simulations]]'''''
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#[[GEOS-Chem chemistry mechanisms|Simulations using KPP-built mechanisms]]
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#[[Aerosol-only simulation]]
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#<span style="color:blue">'''CH4 simulation'''</span>
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#[[CO2 simulation]]
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#[[Mercury|Hg simulation]]
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#[[POPs simulation]]
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#[[Tagged CO simulation]]
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#[[Tagged O3 simulation]]
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#[[TransportTracers simulation]]
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== Overview ==
 
== Overview ==
 
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This page contains information about the methane (CH4) simulation in GEOS-Chem.
=== Authors and collaborators ===
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* [mailto:maasakkers@fas.harvard.edu Bram Maasakkers] ''(Harvard)''
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* Alex Turner ''(Harvard; aturner [at] fas [dot] harvard [dot] edu)''
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* Kevin Wecht ''(formerly @ Harvard)''
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* Christopher Pickett-Heaps ''(formerly @ Harvard)''
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* Jerome Drevet ''(formerly @ EPFL)''
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* James Wang ''(formerly @ Harvard)''
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=== CH4 simulation user groups ===
 
=== CH4 simulation user groups ===
  
{| border=1 cellspacing=0 cellpadding=5
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See [[Carbon_Cycle_Working_Group#Current_Carbon_Cycle_Projects_.28please_add_yours.21.29|this post on the ''Carbon Cycle Working Group'' wiki page]].
|- bgcolor="#cccccc"
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!User Group
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!Personnel
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!Projects
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|-valign="top"
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|[http://acmg.seas.harvard.edu/ Harvard University]
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|[mailto:maasakkers@fas.harvard.edu Bram Maasakkers]<br>[mailto:jsheng@seas.harvard.edu Jianxiong Sheng]<br>Alex Turner
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|North American methane sources;<br>International oil and gas emissions;<br>SCIAMACHY, GOSAT, & TROPOMI
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|-valign="top"
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|}
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=== Tagged CH4 simulation ===
  
=== Notes about the methane simulation ===
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In addition to the standard CH4 simulation, users may also choose to run the tagged CH4 simulation where methane species are tagged by emission source.
 
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:1. '''annual_met.pro:'''  The methane simulation uses monthly and annual average skin temperature and soil moisture values from the met fields.  These are calculated offline using IDL ("annual_met.pro").  This file can be found on the ftp site in the methane data directory with the LPJ wetland emission scheme (e.g., "GEOS_0.5x0.666_NA/CH4_201305/wetlands").  The script should work as is for 2004-2011, however we don't currently have the met data for 2012 so you may need to modify "global_ch4_mod.F" if you're interested in 2012 or 2013.
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:::  '''Subroutine "WETLAND_EMIS"
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        YEAR = GET_YEAR()
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        #if  defined( GEOS_5 )
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        IF ( YEAR .LT. 2004 ) YEAR  = 2004
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        IF ( YEAR .GT. 2011 ) YEAR  = 2011
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:::  '''Subroutine "RICE_EMIS"
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        ! Get annual and monthly mean soil wetness from GEOS
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        ! One file contains both monthly and annual mean GWETTOP
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        YEAR = GET_YEAR()
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        #if  defined( GEOS_5 )
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        IF ( YEAR .LT. 2004 ) YEAR  = 2004
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        IF ( YEAR .GT. 2011 ) YEAR  = 2011
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:2. '''Seasonality of Rice Emissions:'''  Seasonality in the rice emissions is imposed through annual and monthly average soil moisture values.  This works reasonably well for major rice growing areas like South/East Asia where rice paddies are rain-fed, but it fails in other regions.  For example, California rice paddies are irrigated and crops are grown in the summer, precisely when the natural soil is the driest.  You can enter the "global_ch4_mod.F", subroutine "RICE_EMIS", and impose any seasonality you want on the annual emission rates from EDGAR.
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:3. '''Potential Global Mean Bias:'''  The methane simulation may not simulate global average concentrations accurately.  That is, you may have a mean bias of up to +/-30ppbv when you compare the simulation to observations.  A global mean bias means that the model has a slight imbalance between the sources and sinks relative to the world.  You may want to consider removing this mean bias before analyzing your model concentrations.
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--[[User:Alex Turner|Alex Turner]] 11:01, 24 January 2014 (EST)
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== Recent science updates ==
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The following updates were recently added into the GEOS-Chem CH4 simulation:
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=== Update CH4 emissions to EDGAR v4.2 ===
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The CH4 simulation now uses emissions from the EDGAR v4.2 inventory.
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==== In GEOS-Chem v10-01 and newer versions ====
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In [[GEOS-Chem v10-01]] and newer versions, EDGAR v4.2 CH4 emissions are read with the [[HEMCO|HEMCO emissions component]].  We have created [http://ftp.as.harvard.edu/gcgrid/data/ExtData/HEMCO/CH4/v2014-09/README new emission data files for the CH4 simulation] (in [[Preparing data files for use with HEMCO|COARDS-compliant netCDF format]]) for use with HEMCO. These new data files are contained in the [[HEMCO data directories|HEMCO data directory tree]].  For detailed instructions on how to download these data files to your disk server, please see our [[HEMCO_data_directories#Downloading_the_HEMCO_data_directories|''Downloading the HEMCO data directories'' wiki post]].
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--[[User:Bmy|Bob Y.]] 13:23, 3 March 2015 (EST)
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==== In GEOS-Chem versions prior to v10-01 ====
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'''''This update was tested in the 1-month benchmark simulation [[GEOS-Chem_v9-02_benchmark_history#v9-02m|v9-02m]] and approved on 30 Jul 2013.'''''
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'''''This update is included in Adjoint [[GEOS-Chem_Adjoint_v35 | v35d]].'''''
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Kevin Wecht has prepared EDGAR v4.2 emissions of methane for 2004-2008. The data files are available at:
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ftp://ftp.as.harvard.edu/pub/geos-chem/data/GEOS_0.5x0.666_NA/CH4_201305/
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ftp://ftp.as.harvard.edu/pub/geos-chem/data/GEOS_2x2.5/CH4_201305/
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ftp://ftp.as.harvard.edu/pub/geos-chem/data/GEOS_4x5/CH4_201305/
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You can download these directories with anonymous FTP or the Wget utility.  For instructions, please see [http://acmg.seas.harvard.edu/geos/doc/man/chapter_2.html#2.4 Chapter 2.4, Downloading the GEOS-Chem shared data directories] in the GEOS-Chem Online User's Guide.
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Modifications to subroutines <tt>RICE_EMIS</tt> and <tt>ASEASONAL_ANTHRO_EMIS</tt> in <tt>global_ch4_mod.F</tt> include changing the directory names and updating CYEAR and XTAU as follows:
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      WRITE( CYEAR, '(i4)' ) GET_YEAR()
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      XTAU = GET_TAU0( 1, 1, GET_YEAR() )
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      IF ( GET_YEAR() .LT. 2004 )  THEN
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        CYEAR='2004'
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        XTAU = GET_TAU0( 1, 1, 2004 )
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      ENDIF
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      IF ( GET_YEAR() .GT. 2008 ) THEN
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        CYEAR='2008'
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        XTAU = GET_TAU0( 1, 1, 2008 )
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      ENDIF
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--[[User:Melissa Payer|Melissa Payer]] 16:53, 2 July 2013 (EDT)
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===  Update methane emissions and add capability for North America nested grid ===
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<div style="color: #aa0000; background: #eeeeee;border: 3px solid red; padding: 1em; margin: auto; width: 90%; ">'''<p>In [[GEOS-Chem v10-01]] and newer versions, CH4 emissions are implemented via the [[HEMCO|HEMCO emissions component]].</p><p>&mdash; Bob Yantosca, 17 February 2015</p>'''</div>
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'''''This update was tested in the 1-month benchmark simulation [[GEOS-Chem_v9-01-03_benchmark_history#v9-01-03h|v9-01-03h]] and approved on 09 Mar 2012.'''''
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'''''Kevin Wecht wrote:'''''
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:I have some GEOS-Chem methane updates that I'd like to add to the standard code.
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:#GFED emissions - I've updated GFED-2 and GFED-3 biomass burning to include methane emissions.
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:#Methane simulation - I've updated emissions and error catches to make the simulation compatible with the nested simulation over North America. I added linearized CH4 chemistry from GMI output (CH4 loss frequencies generated by Lee Murray). These changes should be made to the data directory:
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:::a. Replace Carbon_soil, Carbon_litter, and Wetfrac files in data directory (for all horizontal resolutions)
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:::b. Add 2010-2011 TSKIN and GWETTOP files to data directory (for all horizontal resolutions)
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:::c. Add nested north american OH files to OH directory
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:::d. Add biofuel emissions to data directory (for all horizontal resolutions)
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:::e. Add all emission files to data directory for nested North America simulation
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The [[CH4_simulation#Error_reading_GWETTOP_fields|error in reading GWETTOP fields]] is also fixed in this update.
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--[[User:Melissa Payer|Melissa Payer]] 17:35, 2 February 2012 (EST)
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== Validation ==
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TBD
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== References ==
 
== References ==
  
 +
#Bloom, A. A., Bowman, K. W., Lee, M., Turner, A. J., Schroeder, R., Worden, J. R., Weidner, R., McDonald, K. C., and Jacob, D. J.: A global wetland methane emissions and uncertainty dataset for atmospheric chemical transport models (WetCHARTs version 1.0), Geosci. Model Dev., 10, 2141-2156, https://doi.org/10.5194/gmd-10-2141-2017, 2017.
 +
#Sheng, J.-X., D. J. Jacob, J.D. Maasakkers, M.P. Sulprizio, D. Zavala-Areiza, and S. Hamburg, A high-resolution (0.1ox0.1o) inventory of methane emissions from Canadian and Mexican oil and gas systems, Atmos. Environ., 158, 211-215, 2017. [[http://www.sciencedirect.com/science/article/pii/S1352231017301164 PDF]]
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#Maasakkers, J.D., D.J.Jacob, M.P. Sulprizio, A.J. Turner, M. Weitz, T. Wirth, C. Hight, M. DeFigueiredo, M. Desai, R. Schmeltz, L. Hockstad, A.A. Bloom, K.W. Bowman, S. Jeong, and M.L. Fischer, Gridded national inventory of U.S. methane emissions, Environ. Sci. Technol., 50, 13123−13133, 2016. [[http://pubs.acs.org/doi/pdf/10.1021/acs.est.6b02878 PDF]]
 
#Turner, A. J., Jacob, D. J., Wecht, K. J., Maasakkers, J. D., Biraud, S. C., Boesch, H., Bowman, K. W., Deutscher, N. M., Dubey, M. K., Griffith, D. W. T., Hase, F., Kuze, A., Notholt, J., Ohyama, H., Parker, R., Payne, V. H., Sussmann, R., Velazco, V. A., Warneke, T., Wennberg, P. O., and Wunch, D.: ''Estimating global and North American methane emissions with high spatial resolution using GOSAT satellite data'', <u>Atmos. Chem. Phys. Discuss.</u>, 15, 4495-4536, doi:10.5194/acpd-15-4495-2015, 2015.
 
#Turner, A. J., Jacob, D. J., Wecht, K. J., Maasakkers, J. D., Biraud, S. C., Boesch, H., Bowman, K. W., Deutscher, N. M., Dubey, M. K., Griffith, D. W. T., Hase, F., Kuze, A., Notholt, J., Ohyama, H., Parker, R., Payne, V. H., Sussmann, R., Velazco, V. A., Warneke, T., Wennberg, P. O., and Wunch, D.: ''Estimating global and North American methane emissions with high spatial resolution using GOSAT satellite data'', <u>Atmos. Chem. Phys. Discuss.</u>, 15, 4495-4536, doi:10.5194/acpd-15-4495-2015, 2015.
 
#Turner, A. J. and Jacob, D. J.: ''Balancing aggregation and smoothing errors in inverse models'', <u>Atmos. Chem. Phys. Discuss.</u>, 15, 1001-1026, doi:10.5194/acpd-15-1001-2015, 2015.
 
#Turner, A. J. and Jacob, D. J.: ''Balancing aggregation and smoothing errors in inverse models'', <u>Atmos. Chem. Phys. Discuss.</u>, 15, 1001-1026, doi:10.5194/acpd-15-1001-2015, 2015.
Line 130: Line 35:
 
#Pickett-Heaps, C.A., D.J. Jacob, K.J. Wecht, E.A. Kort, S.C. Wofsy, G.S. Diskin, D.E.J. Worthy, J.O. Kaplan, I. Bey, and J. Drevet, ''Magnitude of seasonality of wetland methane emissions from the Hudson Bay Lowlands (Canada)'', <u>Atmos. Chem. Phys.</u>, '''11(8)''', 3773-3779, doi:10.5194/acp-11-3773-2011, 2011.
 
#Pickett-Heaps, C.A., D.J. Jacob, K.J. Wecht, E.A. Kort, S.C. Wofsy, G.S. Diskin, D.E.J. Worthy, J.O. Kaplan, I. Bey, and J. Drevet, ''Magnitude of seasonality of wetland methane emissions from the Hudson Bay Lowlands (Canada)'', <u>Atmos. Chem. Phys.</u>, '''11(8)''', 3773-3779, doi:10.5194/acp-11-3773-2011, 2011.
 
#Wang, J.S., J.A. Logan, M.B. McElroy, B.N. Duncan, I.A. Megretskaia, and R.M. Yantosca, ''A 3-D model analysis of the slowdown and interannual variability in the methane growth rate from 1988 to 1997'', <u>Global Biogeochem. Cycles</u>, '''18''', GB3011, doi:10.1029/2003GB002180, 2004.
 
#Wang, J.S., J.A. Logan, M.B. McElroy, B.N. Duncan, I.A. Megretskaia, and R.M. Yantosca, ''A 3-D model analysis of the slowdown and interannual variability in the methane growth rate from 1988 to 1997'', <u>Global Biogeochem. Cycles</u>, '''18''', GB3011, doi:10.1029/2003GB002180, 2004.
 
--[[User:Alex Turner|Alex Turner]] 12:17, 24 February 2015 (EST)
 
 
== Previous issues that are now resolved ==
 
 
The following bugs and/or issues with the code have now been resolved:
 
 
=== Now call INIT_GLOBAL_CH4 from input_mod.F ===
 
 
'''''This update was validated in the 1-month benchmark simulation [[GEOS-Chem v10-01 benchmark history#v10-01c|v10-01c]] and approved on 29 May 2014.'''''
 
 
Prior to [[GEOS-Chem v10-01]], routine <tt>INIT_GLOBAL_CH4</tt> (in module <tt>GeosCore/global_ch4_mod.F</tt>) was called from the main driver routine <tt>main.F</tt> at the start of the simulation.
 
 
In order to make the code more compatible with our [[Grid-Independent GEOS-Chem]] development, we now call <tt>INIT_TAGGED_CH4</tt> from routine <tt>GIGC_INIT_EXTRA</tt> (in module <tt>GeosCore/input_mod.F</tt>).
 
 
--[[User:Bmy|Bob Y.]] 16:59, 30 May 2014 (EDT)
 
 
=== Minor fixes to CH4 simulation for MERRA meteorology ===
 
 
'''''These updates were validated in the 1-month benchmark simulation [[GEOS-Chem v10-01 benchmark history#v10-01c|v10-01c]] and approved on 29 May 2014.'''''
 
 
We have made a couple of fixes to the CH4 simulation module (<tt>GeosCore/global_ch4_mod.F</tt>) for compatibility with the [[MERRA]] met fields.  At lines 1114, and again at line 1503, there were #if blocks that looked like this:
 
 
#if  defined( GEOS_5 ) || defined( GEOS_FP )
 
 
but these should have been:
 
 
#if  defined( GEOS_5 ) || defined( GEOS_FP ) || defined( MERRA )
 
 
Furthermore, in data directory <tt>GEOS_4x5/CH4_201305/wetlands</tt>, we have symbolically linked files:
 
 
GWETTOP.geos5.4x5.YYYY.bpch --> GWETTOP.merra.4x5.YYYY.bpch
 
TSKIN.geos5.4x5.YYYY.bpch  --> TSKIN.merra.4x5.YYYY.bpch
 
 
where <tt>YYYY = { 2004, 2005, 2006, 2007, 2008, 2009, 2010 }</tt>.
 
 
These issues were discovered with the [[GEOS-Chem Unit Tester]].
 
 
--[[User:Bmy|Bob Y.]] 16:59, 30 May 2014 (EDT)
 
 
=== Fixes for wetland emissions ===
 
 
<div style="color: #aa0000; background: #eeeeee;border: 3px solid red; padding: 1em; margin: auto; width: 90%; ">'''<p>In [[GEOS-Chem v10-01]] and newer versions, CH4 emissions are implemented via the [[HEMCO|HEMCO emissions component]].</p><p>&mdash; Bob Yantosca, 17 February 2015</p>'''</div>
 
 
'''''These issues were resolved during the [[GEOS-Chem_v9-02#Period_of_public_comment|public comment period]] following the provisional release of GEOS-Chem v9-02 and were included in the official release of [[GEOS-Chem v9-02]] (03 Mar 2014).'''''
 
'''''This update is included in Adjoint [[GEOS-Chem_Adjoint_v35 | v35j]].'''''
 
 
'''''Kevin Wecht''''' wrote:
 
 
:I have some updates/bug fixes to wetland emissions in the methane simulation. Both changes impact global_ch4_mod.F, subroutine WETLAND_EMIS.
 
 
::1. Christopher Pickett-Heaps added a feature that zeroes wetland emissions if snow covers the ground. This was never incorporated into the standard code. It is included in the attached file.
 
 
::2. Parameters in the subroutine are not correct. The following values are the correct and are included in the attached file:
 
          MOIST_SCALE = 0.205
 
          EMIT_FACT  = 0.018
 
 
--[[User:Melissa Payer|Melissa Sulprizio]] 16:11, 23 January 2014 (EST)<br>
 
--[[User:Bmy|Bob Y.]] 10:25, 4 April 2014 (EDT)
 
 
=== Error reading GWETTOP fields ===
 
 
<div style="color: #aa0000; background: #eeeeee;border: 3px solid red; padding: 1em; margin: auto; width: 90%; ">'''<p>In [[GEOS-Chem v10-01]] and newer versions, CH4 emissions are implemented via the [[HEMCO|HEMCO emissions component]].</p><p>&mdash; Bob Yantosca, 17 February 2015</p>'''</div>
 
 
'''''This update was tested in the 1-month benchmark simulation [[GEOS-Chem_v9-01-03_benchmark_history#v9-01-03h|v9-01-03h]] and approved on 09 Mar 2012.'''''
 
 
There is a file read error in the current CH4 simulation.  We will fix this issue in [[GEOS-Chem v9-01-03]].
 
 
In RICE_EMIS (global_ch4_mod.F), XTAU is reset to the wrong value when GEWTTOP is read. Kevin Wecht provided a fix that accounts for different availabilities of GEOS-4 and GEOS-5 met fields. Prior to setting FILENAME for GWETTOP , add the following:
 
 
      YEAR = GET_YEAR()
 
#if  defined( GEOS_5 )
 
      IF ( YEAR .LT. 2004 ) YEAR  = 2004
 
      IF ( YEAR .GT. 2009 ) YEAR  = 2009
 
#elif defined( GEOS_4 )
 
      IF ( YEAR .LT. 2000 ) YEAR  = 2000
 
      IF ( YEAR .GT. 2006 ) YEAR  = 2006
 
#endif
 
      WRITE( CYEAR, '(i4)' ) YEAR
 
 
:Also change:
 
 
      XTAU = GET_TAU0( 1, 1, GET_YEAR() )
 
and
 
      XTAU = GET_TAU0( GET_MONTH(), 1, GET_YEAR() )
 
 
:to:
 
 
      XTAU = GET_TAU0( 1, 1, YEAR )
 
and
 
      XTAU = GET_TAU0( GET_MONTH(), 1, YEAR )
 
 
--[[User:Melissa Payer|Melissa Payer]] 18:06, 2 February 2012 (EST)
 
 
== Unresolved issues ==
 
 
None reported so far.
 
 
--[[User:Bmy|Bob Y.]] 14:07, 30 March 2012 (EDT)
 

Latest revision as of 14:40, 18 October 2023

Previous | Next | Guide to GEOS-Chem simulations

  1. Simulations using KPP-built mechanisms
  2. Aerosol-only simulation
  3. CH4 simulation
  4. CO2 simulation
  5. Hg simulation
  6. POPs simulation
  7. Tagged CO simulation
  8. Tagged O3 simulation
  9. TransportTracers simulation


Overview

This page contains information about the methane (CH4) simulation in GEOS-Chem.

CH4 simulation user groups

See this post on the Carbon Cycle Working Group wiki page.

Tagged CH4 simulation

In addition to the standard CH4 simulation, users may also choose to run the tagged CH4 simulation where methane species are tagged by emission source.

References

  1. Bloom, A. A., Bowman, K. W., Lee, M., Turner, A. J., Schroeder, R., Worden, J. R., Weidner, R., McDonald, K. C., and Jacob, D. J.: A global wetland methane emissions and uncertainty dataset for atmospheric chemical transport models (WetCHARTs version 1.0), Geosci. Model Dev., 10, 2141-2156, https://doi.org/10.5194/gmd-10-2141-2017, 2017.
  2. Sheng, J.-X., D. J. Jacob, J.D. Maasakkers, M.P. Sulprizio, D. Zavala-Areiza, and S. Hamburg, A high-resolution (0.1ox0.1o) inventory of methane emissions from Canadian and Mexican oil and gas systems, Atmos. Environ., 158, 211-215, 2017. [PDF]
  3. Maasakkers, J.D., D.J.Jacob, M.P. Sulprizio, A.J. Turner, M. Weitz, T. Wirth, C. Hight, M. DeFigueiredo, M. Desai, R. Schmeltz, L. Hockstad, A.A. Bloom, K.W. Bowman, S. Jeong, and M.L. Fischer, Gridded national inventory of U.S. methane emissions, Environ. Sci. Technol., 50, 13123−13133, 2016. [PDF]
  4. Turner, A. J., Jacob, D. J., Wecht, K. J., Maasakkers, J. D., Biraud, S. C., Boesch, H., Bowman, K. W., Deutscher, N. M., Dubey, M. K., Griffith, D. W. T., Hase, F., Kuze, A., Notholt, J., Ohyama, H., Parker, R., Payne, V. H., Sussmann, R., Velazco, V. A., Warneke, T., Wennberg, P. O., and Wunch, D.: Estimating global and North American methane emissions with high spatial resolution using GOSAT satellite data, Atmos. Chem. Phys. Discuss., 15, 4495-4536, doi:10.5194/acpd-15-4495-2015, 2015.
  5. Turner, A. J. and Jacob, D. J.: Balancing aggregation and smoothing errors in inverse models, Atmos. Chem. Phys. Discuss., 15, 1001-1026, doi:10.5194/acpd-15-1001-2015, 2015.
  6. Wecht, K.J., D.J. Jacob, C. Frankenberg, Z. Jiang, and D.R. Blake, Mapping of North America methane emissions with high spatial resolution by inversion of SCIAMACHY satellite data, submitted to J. Geophys. Res., 2014.
  7. Wecht, K.J., D.J. Jacob, M.P. Sulprizio, G.W. Santoni, S.C. Wofsy, R. Parker, H. Bösch, and J.R. Worden, Spatially resolving methane emissions in California: constraints from the CalNex aircraft campaign and from present (GOSAT, TES) and future (TROPOMI, geostationary) satellite observations, Atm. Chem. Phys. Discuss., 14, 4119-4198, doi:10.5194/acpd-14-4119-2014, 2014.
  8. Wecht, K.J., D.J. Jacob, S.C. Wofsy, E.A. Kort, J.R. Worden, S.S. Kulawik, D.K. Henze, M. Kopacz, and V.H. Payne, Validation of TES methane with HIPPO aircraft observations: implications for inverse modeling of methane sources, Atmos. Chem. Phys., 12, 1823-1832, 2012.
  9. Pickett-Heaps, C.A., D.J. Jacob, K.J. Wecht, E.A. Kort, S.C. Wofsy, G.S. Diskin, D.E.J. Worthy, J.O. Kaplan, I. Bey, and J. Drevet, Magnitude of seasonality of wetland methane emissions from the Hudson Bay Lowlands (Canada), Atmos. Chem. Phys., 11(8), 3773-3779, doi:10.5194/acp-11-3773-2011, 2011.
  10. Wang, J.S., J.A. Logan, M.B. McElroy, B.N. Duncan, I.A. Megretskaia, and R.M. Yantosca, A 3-D model analysis of the slowdown and interannual variability in the methane growth rate from 1988 to 1997, Global Biogeochem. Cycles, 18, GB3011, doi:10.1029/2003GB002180, 2004.