Dating qqqa com
IF ( YEAR LAST_TOMS_YEAR ) THEN Input_Opt%USE_O3_FROM_MET = . The Maximum-Random Overlap (MRAN) scheme assumes that clouds in adjacent layers are maximally overlapped to form a cloud block and that blocks of clouds separated by clear layers are randomly overlapped.
If you wish to use the maximum overlap random assumption, change the .
We consider this to be a research option instead of an option for standard GEOS-Chem production runs.
The newer FAST-JX v7.0 photolysis mechanism has been incorporated into the public release of GEOS-Chem v10-01 (). Fortunately, the so-called "approximate" random overlap scheme [TAU' = TAU * f^(3/2) which is computationally cheap] has been demonstrated to be a good approximation to both the "exact" random overlap and MRAN calculations.
The name FAST-J refers to the fact that cross-sections and quantum yields are required for only 7 tropospherically-important wavelength bins. Read data CALL READ_BPCH2( FILENAME, 'TOMS-O3', 2, & XTAU, I1x1, J1x1, & 1, ARRAY1x1, QUIET=. Colette Heald and Randall Martin have added a new capability to the GEOS-Chem v8-03-01 diagnostics that will facilitate comparing GEOS-Chem data to satellite observations.
Other photolysis algorithms had used many more wavelength bins and, as a result, were much more computationally expensive. This was released as a patch shortly after the release of v8-03-01.
For clarity, we have split off the code that reads met ! Lightning NOx emissions are also computed at the same ! When TOMS data is not available, then we will use ! For more details about cloud overlap assumptions and their effect on photolysis frequencies and key oxidants in the troposphere, refer to the following articles: I have a comment about how the effect of cloud overlap in the vertical may be included in GEOS-Chem.
============================================================== CALL READ_MET_FIELDS() #if defined( GEOS_5 ) ! A vertical profile of fractional cloudiness is converted into a series of column configurations with corresponding fractions see Liu et al., JGR 2006; hyl,3/3/04).Only the final 6 bins of Fast-JX data map directly to Fast-J, but for the moment I’ll use bin 12 from Fast-JX as a proxy for bin 1 of Fast-J.