GEOS-Chem ERROR: KPP failed to converge after 2 iterations!

[wahababdul638]

Your name

Abdul Wahab

Your affiliation

Chulalongkorn

What happened? What did you expect to happen?

I was running GEOS-Chem v14.2.3 for my simulation with start date [20220101 00000] and end date [20220901 00000] as shown in log
sim.log14.2.3.txt

The log file had errors like

-> Step size too small: T + 10*H = T or H < Roundoff
T= 4.8000000000000103E-033 and H= 4.8000000000000103E-033

INTEGRATE RETURNED ERROR AT: 49 4 1

Forced exit from Rosenbrock due to the following error:

i looked into previous issues #2195 #2113 #1982 #2006 and other similar issues. The issues are closed with updates in newer model versions. Despite being all my work on v14.2.3, i upgraded it to 14.3.0 and also to 14.4.0 but now i am getting new error, log of which is attached below.

Program received signal SIGSEGV: Segmentation fault - invalid memory reference.
sim.log14.4.0.txt

This error does not give any traceback to look for potential issue, either it is hemco or some other component. Sometime model just stop in attempting to open UCX files and does not go any further, and coredump files.

What are the steps to reproduce the bug?

N/A

Please attach any relevant configuration and log files.

No response

What GEOS-Chem version were you using?

14.2.3, 14.3.0. 14.4.0

What environment were you running GEOS-Chem on?

Local cluster

What compiler and version were you using?

gcc version 11.4.0

Will you be addressing this bug yourself?

Yes

In what configuration were you running GEOS-Chem?

GCClassic

What simulation were you running?

Full chemistry

As what resolution were you running GEOS-Chem?

4x5

What meterology fields did you use?

GEOS-FP

Additional information

No response

[yantosca]

Thanks for writing @wahababdul638. One thing to try is to increase the buffer zone (i.e. where transport boundary conditions are copied but where chemistry is not done).

Default setting

  nested_grid_simulation:
    activate: true
    buffer_zone_NSEW: [3,3,3,3]

Try increasing it to:

  nested_grid_simulation:
    activate: true
    buffer_zone_NSEW: [6,6,6,6]

[wahababdul638]

@yantosca thank you for the comment. i will try to apply this settings, but i want clear out that i was trying to do global 4x5 simulation to get boundary condition files for the geographical area of longitude [ 91E to 127E ] and latitude [ 10S to 29N ].