Aerosol-only simulation

Description

The aerosol simulation is an offline simulation for aerosol tracers only. It uses archived monthly mean OH, NO3, O3 and total nitrate concentrations archived from a previous full-chemistry simulation (more on that below), as well as production and loss rates for H2O2. This simulation does not provide "tagged" capabilities, but reduces the suite of tracers from full chemistry.

Assumptions

1. OH concentrations are taken from a previously run full chemistry simulation. The default is from a much earlier version of the model, when OH thought to be more realistic. The standard code uses OH from version 5-07-08, with GEOS3 meteorology.

2. O3, NO3 and total nitrate (HNO3+NIT) concentrations, as well as production rates and photolysis rates for H2O2 are taken from a previously run full chemistry simulation. The current default fields were produced from a GEOS-4, v7-02-03 simulation.

Standard Tracers

In a complete aerosol-only simulation there are 29 tracers (see input.geos below). This list can be reduced by turning off any aerosol species (eg. SOA, dust, SS, etc).

Practicalities

Offline aerosol is simulation type 10. For a full set of aerosol tracers, the input.geos should look like this: Type of simulation  : 10 Number of Tracers  : 29 Tracer Entries -------> : TR# Name g/mole Tracer Members; () = emitted Tracer #1  : 1 DMS 62.00 Tracer #2  : 2 SO2 64.00 Tracer #3  : 3 SO4 96.00 Tracer #4  : 4 MSA 96.00 Tracer #5  : 5 NH3 17.00 Tracer #6  : 6 NH4 18.00 Tracer #7  : 7 NIT 62.00 Tracer #8  : 8 H2O2 34.00 Tracer #9  : 9 BCPI 12.00 Tracer #10  : 10 OCPI 12.00 Tracer #11  : 11 BCPO 12.00 Tracer #12  : 12 OCPO 12.00 Tracer #13  : 13 ALPH 136.23 Tracer #14  : 14 LIMO 136.23 Tracer #15  : 15 ALCO 142.00 Tracer #16  : 16 SOG1 150.00 Tracer #17  : 17 SOG2 160.00 Tracer #18  : 18 SOG3 220.00 Tracer #19  : 19 SOG4 130.00 Tracer #20  : 20 SOA1 150.00 Tracer #21  : 21 SOA2 160.00 Tracer #22  : 22 SOA3 220.00 Tracer #23  : 23 SOA4 130.00 Tracer #24  : 24 DST1 29.00 Tracer #25  : 25 DST2 29.00 Tracer #26  : 26 DST3 29.00 Tracer #27  : 27 DST4 29.00 Tracer #28  : 28 SALA 36.00 Tracer #29  : 29 SALC 36.00

Recent aerosol-only updates

1.

More Information

For more information, see the GEOS-Chem manual pages about offline aerosols:

http://acmg.seas.harvard.edu/geos/doc/man/chapter_6.html#6.1.6
http://acmg.seas.harvard.edu/geos/doc/man/appendix_1.html#A1.8