How does two-way nesting（feedback=1) handle data exchange when encountering terrains with different resolutions?

[mirabelle]

Dear WRF：

When we use two-way nesting (feedback=1) to run nested areas(d01 and d02 domain), how does the model handle the update of data in the nested area if the terrain resolution of the two areas is different?

For example, if the terrain of fine grid points is mountainous and that of the coarse grid is plain, will the value of the coarse area be replaced by the default value of the fine area? Will this cause disturbance in the coarse grid and increase model uncertainty?

How do the data of the two areas interact in this case?

Besides, the WRF model I am using is V3.7.1.

Thanks.

 

[Ming Chen]

With feedback on, the data on child domain grids will replace that in the parent domain grids. So the answer is yes that value of the coarse area will be replaced by the default value of the fine area. It is expected that the simulation in child domain will be more accurate and thus the feedback will be helpful to also improve the simulation in parent domain.
The parent domain data will provide lateral forcing to chid domain, and thee child domain data will feedback to parent domain. This is how the nesting works in WRF.