Sandbox: Difference between revisions

From Geos-chem
Jump to navigation Jump to search
No edit summary
Line 1: Line 1:
==feel free to experiment here ==
{|border="1" width="1000px" bordercolor="#000000" cellspacing="0" cellpadding="5"
|-valign="middle" height="80" bgcolor="##4494cc;" align="center"
|<p><font color="#FFFFFF" size="+3">'''GEOS&#150;Chem Wiki'''</font></p>
 
|}
 
{|border="0" width="1000px" bordercolor="#FFFFFF" cellspacing="0" cellpadding="5"


{| border=1 bordercolor="#000000" cellpadding="5" cellspacing="0"
|-valign="top"
|-valign="top"
|Yuan_XLAI
|
|DEFAULT
|[[Leaf area indices in GEOS-Chem#Yuan processed MODIS LAI|Yuan processed MODIS LAI data]]
*cf Yuan et al 2011, doi:10.1016/j.rse.2011.01.001


This data has been processed into 73 netCDF variables (one corresponding to each Olson land type), which facilitates regridding by HEMCO.
----
|[ftp://ftp.as.harvard.edu/gcgrid/data/ExtData/HEMCO/Yuan_XLAI/v2019-03/ <tt>HEMCO/Yuan_XLAI/v2019-03</tt>]
 
<p align="center"><big>'''GEOS-Chem Community Mission: to advance understanding of human and natural influences on the environment<br>through a comprehensive, state-of-the-science, readily accessible global model of atmospheric composition.'''</big></p>
 
The [http://acmg.seas.harvard.edu/geos/ GEOS–Chem model] is a global 3-D model of atmospheric composition driven by assimilated meteorological observations from the Goddard Earth Observing System (GEOS) of the [http://gmao.gsfc.nasa.gov/ NASA Global Modeling and Assimilation Office]. It is applied by [http://acmg.seas.harvard.edu/geos/geos_people.html research groups around the world] to a wide range of atmospheric composition problems, Central management and support of the model is provided by the [http://acmg.seas.harvard.edu/index.html Atmospheric Chemistry Modeling Group at Harvard University.]


|}
|}


{|border="1" width="1000px" bordercolor="#000000" cellspacing="0" cellpadding="5"
|-valign="top"
|width="225px" align="center"|<font size="+2">[[GEOS-Chem versions|Past releases]]</font>
|width="450px" align="center" bgcolor="#CCFFFF"|<font size="+2">[[GEOS-Chem 12#12.3.2|'''Current release: GEOS-Chem 12.3.2''']]</font>
|width="225px" align="center"|<font size="+2">[[GEOS-Chem model development_priorities|Future releases]]</font>
|}
[[GEOS-Chem overview]]
== News ==
*[[GEOS-Chem newsletters]]
== Documentation ==


*[[Getting Started with GEOS-Chem]]|
*[[Getting Started with GCHP]]
*[http://cloud.geos-chem.org Running GEOS-Chem on the Amazon Web Services cloud computing platform]
*[http://wrf.geos-chem.org GEOS-Chem coupled with WRF]


=== Quick fix to use Yuan-processed MODIS LAI in GEOS-Chem Classic ===


Bob Yantosca discovered an error when using the Yuan-processed MODIS LAI data in GEOS-Chem "Classic" simulations.  HEMCO cannot locate the proper bounding timestamps for the interpolation.


<blockquote>Example: HEMCO should have detected that simulation date '''20160701''' was bounded by data timestamps '''20160624''' and '''20160704''', and should have interpolated accordingly.  Instead, HEMCO was detecting that simulation data '''20160701''' was bounded by data timestamps '''20160602''' and '''20160610'''.  This is clearly wrong.</blockquote>
*[[GEOS-Chem horizontal grids]]
*[[GEOS-Chem vertical grids]]
* [[Overview of GMAO met data products]]
**[[Version history of GMAO met data products]]
*[[GEOS-Chem emissions]]
*[[GEOS-Chem chemistry mechanisms]]


Christoph Keller traced this error to routine <tt>GET_TIMEIDX</tt> in module <tt>HEMCO/Core/hcoio_read_std_mod.F90</tt>, which is only used for GEOS-Chem "Classic" simulations.  The search algorithm was continuing to look for timestamps further back in time than was necessary.


If you need to run GEOS-Chem simulations with the Yuan-processed MODIS LAI data, Christoph Keller has submitted a quick fix.  Add the IF statement in  <span style="color:green">GREEN</span> to this code in <tt>hcoio_read_std_mod.F90</tt>.  This will force the timestamp search algorithm to terminate before it goes too far back in time.
*[[Species in GEOS-Chem]]
*[[Advection scheme TPCORE]]
*[[Boundary layer mixing]]
*[[Cloud convection]]
*[[Dynamic tropopause]]
*[[Dry deposition]]
**[[Leaf area indices in GEOS-Chem]]
**[[Olson land map]]
*[[Wet deposition]]
*[[GEOS-Chem aerosols]]


        ! -------------------------------------------------------------
*[[Aerosol-only simulation]]
        ! Check if we need to continue search. Even if the call above
*[[Aerosol optical properties]]
        ! returned a time slice, it may be possible to continue looking
*[[Aerosol thermodynamical equilibrium]]
        ! for a better suited time stamp. This is only the case if
*[[Carbonaceous aerosols]]
        ! there are discontinuities in the time stamps, e.g. if a file
*[[Mineral dust aerosols]]
        ! contains monthly data for 2005 and 2020. In that case, the
*[[Secondary organic aerosols]]
        ! call above would return the index for Dec 2005 for any
*[[Sea salt aerosols]]
        ! simulation date between 2005 and 2010 (e.g. July 2010),
*[[Sulfate aerosols]]
        ! whereas it makes more sense to use July 2005 (and eventually
*Aerosol Microphysics
        ! interpolate between the July 2005 and July 2020 data).
**[[APM aerosol microphysics|APM]]
        ! The IsClosest command checks if there are any netCDF time
**[[TOMAS aerosol microphysics|TOMAS]]
        ! stamps (prior to the selected one) that are closer to each
        ! other than the difference between the preferred time stamp
        ! prefYMDhm and the currently selected time stamp
        ! availYMDhm(tidx1a). In that case, it continues the search by
        ! updating prefYMDhm so that it falls within the range of the
        ! 'high-frequency' interval.
        ! -------------------------------------------------------------
        ExitSearch = .FALSE.
        IF ( Lct%Dct%Dta%CycleFlag == HCO_CFLAG_EXACT ) THEN
          ExitSearch = .TRUE.
        ELSE IF ( tidx1a > 0 ) THEN
          ExitSearch = IsClosest( prefYMDhm, availYMDhm, nTime, tidx1a )
        ENDIF
        <span style="color:green">!### for testing, only apply to containers with “XLAI” in the name
        IF ( INDEX( Lct%Dct%Cname, 'XLAI' ) > 0 ) THEN
          ExitSearch = .true.
        ENDIF</span>


We will try to add a more robust fix for this issue in the near future.  We did not want to add a fix that was contingent on a HEMCO container name to the standard code.
*[[GEOS-Chem_benchmarking]


NOTE: GCHP is unaffected by this issue, as it uses the MAPL ExtData functionality to read data from disk.  We have verified that GCHP reads in the Yuan-processed MODIS LAI data properly.
*Available diagnostics in GEOS-Chem
**[[List of diagnostics archived to netCDF format|NetCDF format]]
**[[List of diagnostics archived to bpch format|Binary punch (aka bpch) format]]
**[[ObsPack diagnostic]]
**[[Planeflight diagnostic]]
*[[The HEMCO User's Guide#Diagnostics|Archiving diagnostics from HEMCO to netCDF files]]
*[[Diagnostic time step]]
*[[Additional diagnostics]]


--[[User:Bmy|Bob Yantosca]] ([[User talk:Bmy|talk]]) 19:23, 7 June 2019 (UTC)
== GEOS-Chem flavors ==
*[[GEOS-Chem HP]]
*[[GEOS-Chem Adjoint]]
*[[Coupling GEOS-Chem with other models]]
*[[GEOS-Chem nested grid simulations]]

Revision as of 01:18, 12 June 2019

GEOS&#150;Chem Wiki

GEOS-Chem Community Mission: to advance understanding of human and natural influences on the environment
through a comprehensive, state-of-the-science, readily accessible global model of atmospheric composition.

The GEOS–Chem model is a global 3-D model of atmospheric composition driven by assimilated meteorological observations from the Goddard Earth Observing System (GEOS) of the NASA Global Modeling and Assimilation Office. It is applied by research groups around the world to a wide range of atmospheric composition problems, Central management and support of the model is provided by the Atmospheric Chemistry Modeling Group at Harvard University.

Past releases Current release: GEOS-Chem 12.3.2 Future releases

GEOS-Chem overview

News

Documentation



  • [[GEOS-Chem_benchmarking]

GEOS-Chem flavors

Retrieved from "https://wiki.seas.harvard.edu/geos-chem/index.php?title=Sandbox&oldid=42092"