Convergence for Multilayer Model w Surface Runoff

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TSal
Posts: 3
Joined: Tue Feb 09, 2021 3:57 am
Location: USA

Convergence for Multilayer Model w Surface Runoff

Post by TSal » Tue Feb 09, 2021 2:09 pm

Question for the community: I have a multi-year (daily climate simulation) multi-layer (four layer) model where the upper two layers are moving towards saturation temporarily by large storm events. The coarser bottom layer remains well below saturation. The climate simulation was developed with HELP and detailed scrutiny of the data indicates that the larger precipitation events in the synthetic dataset are reasonable. The model is having trouble converging during these larger precip days; the data indicates that the upper two soil layers are nearing saturation, but the lower coarser layers are unsaturated. The upper BC is specified to generate runoff.

I am having difficulty troubleshooting the source of the error; or better said the reason for the error. Perusal of this forum and previous guidance indicates it is a function of the soil column hitting saturation, but with runoff generated and an unsaturated lower portion of the model, it seems like there should be sufficient storage for the precipitation event.

Thoughts on what is going on or how to modify this simulation to move past the convergence problems?
Thank you,
TSal

TSal
Posts: 3
Joined: Tue Feb 09, 2021 3:57 am
Location: USA

Re: Convergence for Multilayer Model w Surface Runoff

Post by TSal » Thu Feb 11, 2021 7:00 pm

Attached is a typical model where the convergence problem manifests.

Regards,
TSal
Attachments
2021.02.03.100yrFLAT.7z
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