Wetting and drying in z* coordinates - bad idea?
Opened this issue · 2 comments
For historical reasons, our regional domains started with the z* vertical coordinate. Most have continued using z* because the OBCs work better that way. We now have a Gulf of Alaska domain in which we would eventually like to have wetting and drying. Both Cook Inlet and the Copper River delta have tidal mud flats. Setting the MASKING_DEPTH to -20 and MINIMUM_DEPTH to -10 causes the model to blow up:
FATAL from PE 42: MOM_regridding: adjust_interface_motion() - implied h<0 is larger than roundoff!
Trying again with MASKING_DEPTH = 0 and MINIMUM_DEPTH = 1 allows it to run. Does it make sense to have these values match? Am I setting them wrong or is z* the problem?
Another thing about very shallow depths is that ice can form there, inducing brine rejection and this failure:
FATAL from PE 4: There were a total of 4 locations detected with extreme surface values!
WARNING from PE 34: Extreme surface sfc_state detected: i= 242 j= 187 lon=-144.672 lat= 60.196 x=-136.064 y= 55.549 D= 1.0000E-10 SSH= 1.5298E-03 SST=-3.1641E+00 SSS= 5.8595E+01 U-=-8.1887E-09 U+= 0.0000E+00 V-=-1.4694E-07 V+=-3.6210E-08
Perhaps this belongs in SIS2?
It's the ALE remapping that has trouble with the dry beach cells. There are no target depths climbing up onto the mud flats.