Difference between revisions of "TransportTracers simulation"

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(Bug for ND44 diagnostic in diag3.f)
(Known issues)
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#Lal, D., and B. Peters, ''Cosmic ray produced radioactivity on the Earth''. <u>Handbuch der Physik</u>, '''46/2''', 551-612, edited by K. Sitte, Springer-Verlag, New York, 1967.  
 
#Lal, D., and B. Peters, ''Cosmic ray produced radioactivity on the Earth''. <u>Handbuch der Physik</u>, '''46/2''', 551-612, edited by K. Sitte, Springer-Verlag, New York, 1967.  
  
== Known issues ==
+
== Previous issues that are now resolved ==
  
 
=== Incorrect Rn values caused by bug in convection_mod.f ===
 
=== Incorrect Rn values caused by bug in convection_mod.f ===
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=== Bug for ND44 diagnostic in diag3.f ===
 
=== Bug for ND44 diagnostic in diag3.f ===
 +
 +
'''''NOTE: This bug was issued as a post-release patch ("v9-01-01-Patch-diags") in [[GEOS-Chem v9-01-01]] and was approved on 07 Jun 2011.'''''
  
 
In the ND44 diagnostic section of <tt>diag3.f</tt>, the following lines are present twice (once for drydep fluxes and again for drydep velocities).  This is a special-case for some tracers in the Caltech isoprene scheme:
 
In the ND44 diagnostic section of <tt>diag3.f</tt>, the following lines are present twice (once for drydep fluxes and again for drydep velocities).  This is a special-case for some tracers in the Caltech isoprene scheme:
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             ENDIF
 
             ENDIF
  
We will add this fix into [[GEOS-Chem v9-01-02]].  If you are using a prior version, then please apply this fix in your own codes for the time being.
+
--[[User:Bmy|Bob Y.]] 11:57, 7 July 2011 (EDT)
 +
 
 +
== Outstanding issues ==
 +
 
 +
=== Missing drydep diagnostics caused by tracer name error  ===
 +
 
 +
Please use the following tracer names in <tt>input.geos</tt> when setting up a Rn-Pb-Be simulation:
 +
 
 +
%%% TRACER MENU %%%    :
 +
Type of simulation      : 1
 +
Number of Tracers      : 3                     
 +
Tracer Entries -------> : TR#  Name  g/mole  Tracer Members; () = emitted
 +
Tracer #1              :  1  Rn    222.0 
 +
Tracer #2              :  2  Pb    210.0
 +
Tracer #3              :  3  Be7      7.0
 +
 
 +
If you use alternate spellings for the Rn and Pb tracers, such as:
 +
 
 +
Tracer #1              :  1  Rn222  222.0 
 +
Tracer #2              :  2  Pb210  210.0
 +
 
 +
Then this may cause the dry deposition fluxes and frequencies for Pb<sup>210</sup> not to be printed out.
 +
 
 +
A fix is forthcoming in [[GEOS-Chem v9-01-02]].
  
--[[User:Bmy|Bob Y.]] 14:58, 20 May 2011 (EDT)
+
--[[User:Bmy|Bob Y.]] 11:57, 7 July 2011 (EDT)

Revision as of 15:57, 7 July 2011

This page contains information about the Radon-Lead-Beryllium simulation in GEOS-Chem.

Overview

The Rn-Pb-Be simulation in GEOS-Chem was based on that of the old Harvard/GISS CTM model. The current simulation follows Liu et al [2001].

The standard Rn-Pb-Be simulation uses the following tracers:

  1. Rn222, which is emitted naturally from soils
  2. Pb210, which is the primary decay product of Rn222
  3. Be7, which is produced by cosmic rays in the stratosphere and upper atmosphere

This simulation is most frequently used to validate the convection and advection processes in GEOS-Chem.

Sources

The source of #Rn222 is determined as follows (cf. Jacob et al [1997]):

  1. Rn222 emission poleward of 70 degrees = 0.0 [atoms/cm2/s]
  2. For latitudes 70S-60S and 60N-70N (both land & ocean), Rn222 emission = 0.005 [atoms/cm2/s]
  3. For latitudes between 60S and 60N:
    • Rn222 over land = 1 [atoms/cm2/s] over land
    • Rn222 over land = 0.005 [atoms/cm2/s] over oceans
  4. Where the surface temperature is below 0° C, reduce Rn222 emissions by a factor of 3.

The source of Be7 is taken from Lal and Peters [1967].

Sinks

Rn222 decays into Pb210 according to the exponential law: EXP( -ΔT * 2.097d-6 )

Pb210 decays according to the exponential law: EXP( -ΔT * 9.725d-10 )

Be7 decays according to the exponential law: EXP( -ΔT * 1.506d-7 )

where -ΔT is the emission timestep in seconds.

Validation

See Liu et al [2001].

References

  1. Liu, H., D. Jacob, I. Bey, and R.M. Yantosca, Constraints from 210Pb and 7Be on wet deposition and transport in a global three-dimensional chemical tracer model driven by assimilated meteorological fields, J. Geophys. Res, 106, D11, 12,109-12,128, 2001.
  2. Jacob et al., Evaluation and intercomparison of global atmospheric transport models using Rn-222 and other short-lived tracers, J. Geophys. Res, 102, 5953-5970, 1997.
  3. Koch, D. J. Geophys. Res, 101, D13, 18651, 1996.
  4. Lal, D., and B. Peters, Cosmic ray produced radioactivity on the Earth. Handbuch der Physik, 46/2, 551-612, edited by K. Sitte, Springer-Verlag, New York, 1967.

Previous issues that are now resolved

Incorrect Rn values caused by bug in convection_mod.f

The bug in convection_mod.f described here can cause incorrect values of Rn in GEOS-Chem v8-03-01 and prior versions.

--Bob Y. 16:17, 19 May 2011 (EDT)

Bug for ND44 diagnostic in diag3.f

NOTE: This bug was issued as a post-release patch ("v9-01-01-Patch-diags") in GEOS-Chem v9-01-01 and was approved on 07 Jun 2011.

In the ND44 diagnostic section of diag3.f, the following lines are present twice (once for drydep fluxes and again for drydep velocities). This is a special-case for some tracers in the Caltech isoprene scheme:

              ! Special case for tracers with several dry dep. tracers
              ! E.g. ISOPN: ISOPND and ISOPNB.
              ! We handle both tracers at the same time so we need to 
              ! skip the second tracer. (ccc, 2/3/10)
              !IF ( MMB /= NN ) CYCLE
              IF ( MMB /= NN                .OR.
    &              DEPNAME( N ) == 'ISOPNB' .OR.
    &              DEPNAME( N ) == 'MVKN'       ) CYCLE

However, these lines will cause the drydep fluxes and velocities for Be7 to be skipped. The fix is to bracket these lines with an IF statement so that they will only execute for a full-chemistry simulation:

           IF ( ITS_A_FULLCHEM_SIM() ) THEN
              ! Special case for tracers with several dry dep. tracers
              ! E.g. ISOPN: ISOPND and ISOPNB.
              ! We handle both tracers at the same time so we need to 
              ! skip the second tracer. (ccc, 2/3/10)
              !IF ( MMB /= NN ) CYCLE
              IF ( MMB /= NN                .OR.
    &              DEPNAME( N ) == 'ISOPNB' .OR.
    &              DEPNAME( N ) == 'MVKN'       ) CYCLE
           ENDIF

--Bob Y. 11:57, 7 July 2011 (EDT)

Outstanding issues

Missing drydep diagnostics caused by tracer name error

Please use the following tracer names in input.geos when setting up a Rn-Pb-Be simulation:

%%% TRACER MENU %%%     : 
Type of simulation      : 1
Number of Tracers       : 3                      
Tracer Entries -------> : TR#   Name  g/mole   Tracer Members; () = emitted 
Tracer #1               :   1   Rn     222.0  
Tracer #2               :   2   Pb     210.0
Tracer #3               :   3   Be7      7.0

If you use alternate spellings for the Rn and Pb tracers, such as:

Tracer #1               :   1   Rn222  222.0  
Tracer #2               :   2   Pb210  210.0

Then this may cause the dry deposition fluxes and frequencies for Pb210 not to be printed out.

A fix is forthcoming in GEOS-Chem v9-01-02.

--Bob Y. 11:57, 7 July 2011 (EDT)