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ESCOMP / CTSM

Community Terrestrial Systems Model (includes the Community Land Model of CESM)
http://www.cesm.ucar.edu/models/cesm2.0/land/
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Dynamic lakes will need to receive lake removed by ROF model #1259

Open ekluzek opened 3 years ago

ekluzek commented 3 years ago

As a future development of dynamic lakes (see #1206) we'll need to receive the amount of water removed from lakes by the ROF model. Normally this will be just the reverse of the Precip minus Evaporation that's sent to ROF, but when lakes are empty or near empty it will be less than that. Since, it likely won't happen that often we figure we can ignore this effect initially. But, for completeness and in order to connect to an ocean model we'll likely need to put it in place.

Note, that there is a similar issue with glaciers that we ignore. And this is similar to how irrigation is currently handled in CTSM. We'll likely need to implement something similar to how irrigation, which means a field sent from ROF to CTSM to track it and then CTSM will need to react to the field sent back.

In mizuRoute this is documented as...

https://github.com/NCAR/mizuRoute/issues/170

billsacks commented 3 years ago

As we discussed in the ctsm-software meeting, I believe there are three different ways to handle this:

A few ways we could handle this:

  1. Send back an "unmet flux" to CTSM. We've thought about doing this for ice sheets, but never implemented it. This is similar to what @ekluzek mentions in his first paragraph.
  2. Do something similar to irrigation, where we have a limit based on available water. Maybe the best, though I remembers some subtleties with this. Note that this differs from the first option: with this option, CTSM knows the amount of water available and avoids setting a flux higher than this availability.
  3. Do something similar to what happens with irrigation without the volr limiting: have ROF pull extra from the ocean.
ekluzek commented 3 years ago

Note the field transferred will also need to be added to CMEPS. And we likely will need to make sure the MCT mediator isn't used as we probably won't implement it there.

https://github.com/ESCOMP/CMEPS/issues/153