queries regarding outputs

[Aarti Soni]

Dear All,

I have some doubts regarding the output (figures are attached).

 

1. Why the WA/WT (water in aquifer) and ZWT (depth to water table) variables are showing one single value in the entire domain?  

2. In GWOUT output, the size of inflow, outflow, and depth is 56910x1 while my domain size is 499x799. So what does this 56910 represent here?

Thank you.

[Natalia Carrera Ávila]

Hello everyone!

I have found something similar in my results, and also in the example cases called Gridded and Reach. I've seen ZWT, WT and WA variables have constant (in time) and homogeneous (through the domain) values. On the other hand, a similar variable as ZWT (zwattablrt) has different values along the domain in the examples (sadly, not yet in my run) which seems to me more realistic, yet in the RESTART files I've only found the variables ZWT, WA and WT. Why is this??

I appreciate any comments on this.

Natalia.

[aubrey]

Hi Natalia & Aarti:

I believe ZWT, WT and WA are Noah-MP output variables and are specific to the TOPMODEL (RUNOFF_OPTION = 1 or 2) or MMF (RUNOFF_OPTION = 5) groundwater routing schemes. We do not currently support the MMF configuration when running WRF-Hydro since there is no mechanism to connect the MMF groundwater discharge to WRF-Hydro streams (and that scheme is really intended for much coarser representations than we generally run for WRF-Hydro). Instead, if a user thinks there is a deeper groundwater contribution that the simple WRF-Hydro baseflow formulations cannot handle, we encourage the user to use the built-in WRF-Hydro subsurface lateral flow routines and extend the soil depth/layers to approximate deeper groundwater flow. I have not worked much with the Noah-MP TOPMODEL schemes as we found they did not perform very well for runoff processes (ok for more humid regions). If you are running with RUNOFF_OPTION = 3 or 7 (what we generally recommend), these variables are not used and you should rely on the WRF-Hydro shallow water table outputs (these will be in RTOUT and HYDRO_RST, not the land model outputs or restarts).

When you are using the WRF-Hydro conceptual baseflow model, you are prescribing groundwater "basins" (there should have been created when you ran the GIS pre-processor). So the number of records in the GWOUT files corresponds to the number of groundwater basins you setup in the GIS pre-processor. The user is free to set these up how they want, depending on the main hydrologic drivers in your region and your application.

See the user guide for more:

https://wrf-hydro.readthedocs.io/en/latest/model-physics.html#conceptual-base-flow-model-description

Thanks!

Aubrey