Difference between revisions of "NOx-Ox-HC-aerosol"

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== CH4 concentrations ==
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'''''Chris Buten (cbuten@pdx.edu) wrote:'''''
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:When running the NOxOxHC simulation, I presume that CH4 concentration is specified as an input and not determined by emissions and transport (and therefore not a tracer). If so, is there a way to easily visualize or extract these input concentrations?
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'''''Bob Yantosca (yantosca@seas.harvard.edu) wrote:'''''
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:Yes, in the full chemistry mechanism, CH4 is a constant.  The values for years and latitude bands are set by routine get_global_ch4.f.
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--[[User:Bmy|Bob Y.]] 09:52, 14 July 2008 (EDT)
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== FAST-J Photolysis ==
 
== FAST-J Photolysis ==
  

Revision as of 13:52, 14 July 2008

CH4 concentrations

Chris Buten (cbuten@pdx.edu) wrote:

When running the NOxOxHC simulation, I presume that CH4 concentration is specified as an input and not determined by emissions and transport (and therefore not a tracer). If so, is there a way to easily visualize or extract these input concentrations?

Bob Yantosca (yantosca@seas.harvard.edu) wrote:

Yes, in the full chemistry mechanism, CH4 is a constant. The values for years and latitude bands are set by routine get_global_ch4.f.

--Bob Y. 09:52, 14 July 2008 (EDT)

FAST-J Photolysis

NOTE: This discussion has now been moved to the Photolysis mechanism page.

Variable Tropopause

25-Sep-2007

  1. Note that the implementation of the variable tropopause is buggy in versions prior to GEOS-Chem v7-04-12. If you are using versions prior to v7-04-12, you should turn the variable tropopause OFF.
  2. Jennifer Logan (see correspondence below) suggested that we should cap the variable tropopause at 200hPa in near-polar regions (90-60S and 60-90N), to avoid the problem with anomalously high tropopause heights at high latitudes. This fix was not in v7-04-12, but will be implemented into GEOS-Chem internal version v7-04-13.


Jennifer Logan (jlogan@seas.harvard.edu) wrote:
After looking at the two papers I sent, I think we should restrict the tropopause at latitudes > 60 deg. to pressures greater than 200 mb (about 11 km). From Fig. 3 in Seidel and Randel, there are tropopause (TP) heights as high as 13.5 km in the Antarctic (median height is ~9.8 km, 250 mb), but I don't think we want to be doing trop. chem there. The median TP pressure at ~80 N is ~300 mb, compared to ~250 mb at 70-85 S. The extratropical TP heights are higher (lower pressure) in the SH than in the NH according to Fig. 3.
This approach is also very easy to explain in a paper.
Jennifer

Other errors in SMVGEAR

  • Click HERE for a description of the SMVGEAR bug that caused concentrations of certain tracers in STT to go to zero. This bug was fixed by May Fu and Philippe Le Sager.
  • Lok Lamsal reported a bug with NaN's in SMVGEAR. Bob Yantosca recommended a fix for this error. Click HERE to visit the discussion in the Bug Fixes Forum.