Fatal Error and Dissolved Oxygen Problems

Question

I am not sure if this is related, but at a particular point in the model run, oxygen at the inlet goes to zero and then rapidly spreads (at 0 mg/L) across the entire lake. Soon after I get the fatal error.  Thank you again for your patience with all these questions. See error below.

**** WARNING **** WARNING **** WARNING **** WARNING ****
 * Dissolved Oxygen limit of 25mg/l violated
 *           47  cells have been limited
 *********************************************************
 
 ***** FATAL ERROR **** FATAL ERROR **** FATAL ERROR *****
 * in module     
 * in subroutine get_surface_and_bottom_maps
 * Surface is too high for domain: Face c
 *   Column:          1 i:       108 j:         2
 *   Height:          NaN
 *********************************************************

Answer 1

Hi, sorry for the delay in responding I've been a bit snowed under with project work.

Large DO concentrations are usually caused by excessive algal growth.  The model doesn't do any oxygen solubility check but instead limit DO to less than 25mg/L.

The key is to use the algal limitation functions to reproduce sensible algal dynamics.

Also, you should download the latest model version, I've just found a small bug in the temperature limitation function.

Chris