Fix stability issues in the coupling of LandModel (soil + snow + canopy) - #170
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- VPD is now clipped from below at 0.1 kPa to avoid dvision by zero - Fixed dimensional inconsistencies in stomatal conductance formula - Added diffusivity ratio of water to CO2 as struct field rather than magic constant
Adds integration tests with LandModel that stress test the implicit skin temperature solver over a coarse grid of meteorological conditions.
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LandModel (soil + snow + canopy)
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Co-authored-by: Maximilian Gelbrecht <maximilian.gelbrecht@posteo.de>
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This PR is a collection of fixes that were necessary to get the coupling of the full
LandModelwithPrescribedVegetationandSingleLayerSnowsemi-working with both SpeedyWeather and ERA5-Land forcing.Summary of changes
MedlynStomatalConductanceto (a) be more physically consistent, and (b) handle corner cases like where the VPD is zero andAn < 0(@mahabadri)CanopyWaterInterceptionaccumulating negative water storage; clamping of the water storage term in each timestep should be added in a later PRPALADYNCanopyEvapotranspirationallowing for negative transpiration; the transpirative humidity flux is now clamped at zero, but deposition may still occur via the canopy termcompute_transpiration_conductancethat allowed for nonzero transpiration over unvegetated grid cellsR_vandR_din Thermodynamics constants to increase accuracy of derived universal gas constant