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start:hype_model_description:processes_above_ground [2018/08/10 15:41]
cpers [Precipitation adjustments]
start:hype_model_description:processes_above_ground [2018/08/10 15:43] (current)
cpers [Evaporation]
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 Evaporation from soil is assumed to occur from the two upper layers. The potential evaporation is assumed to decrease exponentially with depth (depending on the parameter //​epotdist//​). The potential evaporation is divided between the two layers (//​epotfrac//​) with the distribution depending on the potential evaporation in the midpoint of each soil layer (figure 1). This is then used by approximating to a rectangle. Since soil layers differ between classes, the evaporation distribution do to. Evaporation from soil is assumed to occur from the two upper layers. The potential evaporation is assumed to decrease exponentially with depth (depending on the parameter //​epotdist//​). The potential evaporation is divided between the two layers (//​epotfrac//​) with the distribution depending on the potential evaporation in the midpoint of each soil layer (figure 1). This is then used by approximating to a rectangle. Since soil layers differ between classes, the evaporation distribution do to.
  
-<m> epot1 = EXP(-epotdist*soillayerdepth(1){/​}2) </m>+<m> epot1 = EXP(- epotdist*soillayerdepth(1){/​}2) </m>
  
-<m> epot2 = EXP(-epotdist*(soillayerdepth(1)+{soillayerdepth(2)-+<m> epot2 = EXP(- epotdist*(soillayerdepth(1)+{soillayerdepth(2)-
           soillayerdepth(1)}/​2)) </m>           soillayerdepth(1)}/​2)) </m>
           ​           ​
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 The actual evaporation is set to zero for temperatures below the threshold temperature and for negative potential evaporation estimates (condensation). The soil evapotranspiration reduction is calculated as: The actual evaporation is set to zero for temperatures below the threshold temperature and for negative potential evaporation estimates (condensation). The soil evapotranspiration reduction is calculated as:
  
-<m> factor = 1-e^(-tredA*(soiltemp-ttrig)^tredB) </m>+<m> factor = 1-e^( - tredA*(soiltemp-ttrig)^tredB) </m>
  
 <m> evapp = evapp*factor </m> <m> evapp = evapp*factor </m>
start/hype_model_description/processes_above_ground.txt ยท Last modified: 2018/08/10 15:43 by cpers