search

EDmodel / ED2

Ecosystem Demography Model
78 stars 112 forks source link

Transpiration too high #48

Closed crollinson closed 9 years ago

crollinson commented 9 years ago

Hi Everyone,

I'm trying to do a bare-ground spinup at 6 sites and am encountering a problem where the soil moisture gets extremely dry (as dry as it can physically be) due to transpiration after some period of time (10-50 years). Has anybody else been having this or a similar problem? Or transpiration just being extremely high?

Mean June transpiration at Harvard Forest 10 years into a bare ground spin is 3.7e-5 kg/m2/s and I'm losing 1e-6 to 4e-6 kg/m2/s from the different soil layers due to transpiration.

Does anybody have any suggestions on where to look to try and crank transpiration down? I've tried tweaking just about every photosynthesis or leaf-area related PFT parameter and ED2IN setting imaginable, so I think there might be a bug that's not closing enough stomata or letting photosynthesis saturate, but I'm not sure. If it helps, my base PFT parameterization file (which I've been tweaking) can be found here: https://github.com/crollinson/ED_Processing/blob/master/PalEON_Phase1a.v2.xml

If anybody has any thoughts, I'd really appreciate it!

crollinson commented 9 years ago

I'm back to thinking there isn't a bug and I just need to dramatically crank down my D0 parameter. I'll close this issue once I get a spinup with reasonable trees & soil moisture.

crollinson commented 9 years ago

Turns out this my problem was not having the flag to recalculate the shortwave radiation components turned on. Problem solved.