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ASTEM internal step exceeded 200 + forced exit from Rosenbrock

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New member
Hi all,

I am trying to run WRF-Chem (version: 4.0.2, compiler: gfortran, chem_opt=202), but when I run ./wrf.exe, I experience the following errors:

d01 2010-04-01_00:03:00 kpp_mechanism_driver: calling mozart_mosaic_4bin_aq_interface
Forced exit from Rosenbrock due to the following error:
Step size too small

and a bit later:

d01 2010-04-01_00:03:00 aerosols_driver calling mosaic_aerchem_driver
ASTEM internal steps exceeded 200

The thing is that the model runs for several hours (really slowly) giving this outputs errors at every time step before actually crashing.

What may cause the problem?

I attach here my namleist.input and the rsl.000 and rsl.out files.

View attachment rsl_out.txt
View attachment rsl_error0000.txt
View attachment namelist.input

Thanks in advance!