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start:hype_model_description:hype_land [2018/10/16 08:35]
cpers [Links to file reference]
start:hype_model_description:hype_land [2019/03/19 14:19]
cpers [Diagnostic variables]
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 Some additional output variables are calculated from the soil state variables. ​ Some additional output variables are calculated from the soil state variables. ​
  
-=== Ground water level ===+=== Groundwater ​level ===
  
-A water table is calculated for each soil layer (//gwat//from the proportion ​of water-filled pores of effective porosity. If the ground water reaches above the surface, the water is calculated with 100% porosity.+The groundwater level is measured negative from surface ​(0mto bottom ​of the soil layers. A positive groundwater level means that the soil surface is below water. If the ground water table reaches above the surface, the water is calculated with 100% porosity.
  
-  IF(soil(k)-wp(k)-fc(k)>​0.0) +The water table is found in the lowest ​soil layer that is not completely filled with water. Soil layers above this layer may have water in its effective porosity, but that is not included in the groundwater level output variable.  
-    ​gwat(k) = (soil(k)-wp(k)-fc(k)-ep(k))/​ep(k) * soillayerthick(k) –  +The water table for a soil layer is calculated linearly from the proportion of water-filled pores of effective porosity part of the soil pore volume. If the soil moisture of a soil layer is at field capacity ​(or below), the groundwater level of that soil layer is at the bottom of the layer. If the pore volume is filled, the groundwater level of that soil layer is at the top of the layer
-               ​soillayerdepth(k-1) +
-  IF(gwat(1) > 0) gwat(1) = (soil(1)-wp(1)-fc(1)-ep(1))/​1000.+
  
-The water table measured as a negative from ground surface to bottom. A positive ground water table means that the land is under water. ​ 
-The lowest soil layer that is not completely filled with water is defined as the "​official"​ ground water table layer and is the one being printed. Soil layers above this may have water in its effective porosity. ​ 
  
 === Soil moisture deficit === === Soil moisture deficit ===
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 ==== Soil temperature and snow depth ==== ==== Soil temperature and snow depth ====
  
-Soil layer temperature (//​soiltemp//​) is calculated as a balance of three temperatures;​ previous time step soil layer temperature,​ soil temperature at deep depth (//​deeptemp//​) and air temperature (//temp//). The weight of the deep soil is constant (0.001), while the weight of the air temperature (//​weightair//​) depends on snow depth (//​snowdepth//​) and parameters. The soil memory (//​soilmem//​) depends on depth and land use, with parameters //surfmem// and //​depthrel//​. The memory of deep soil temperature is a general parameter (//​deepmem//​).+Soil layer temperature (//​soiltemp//​) is calculated as a balance of three temperatures;​ previous time step soil layer temperature,​ soil temperature at deep depth (//​deeptemp//​) and air temperature (//T//). The weight of the deep soil is constant (0.001), while the weight of the air temperature (//​weightair//​) depends on snow depth (//​snowdepth//​) and parameters. The soil memory (//​soilmem//​) depends on depth and land use, with parameters //surfmem// and //​depthrel//​. The memory of deep soil temperature is a general parameter (//​deepmem//​).
  
 <m> soilmem = {lbrace}{ <m> soilmem = {lbrace}{
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 <m> weigth_{air}={1}/​{soilmem+10*snowdepth} </m> <m> weigth_{air}={1}/​{soilmem+10*snowdepth} </m>
  
-<m> deeptemp=weight_{air}*temp+(1-weight_{air})*deeptemp </m>+<m> deeptemp=weight_{air}*T+(1-weight_{air})*deeptemp </m>
  
-<m> soiltemp=weight_{air}*temp+(1-weight_{air}-weight_{deep} )*soiltemp+weight_{deep}*deeptemp </m>+<m> soiltemp=weight_{air}*T+(1-weight_{air}-weight_{deep} )*soiltemp+weight_{deep}*deeptemp </m>
  
 In the default snow depth model, snow density (//​snowdens//​) depends on the snow's age in days (//​snowage//​). Snow density for fresh snow (//​sdnsnew//​) and the increase of density with snow age (//​snowdensdt//​) are general parameters (~ 0.1 and ~0.002). The snow's age increases by one every time step, but are weighted with age (0) for any new snow. In the default snow depth model, snow density (//​snowdens//​) depends on the snow's age in days (//​snowage//​). Snow density for fresh snow (//​sdnsnew//​) and the increase of density with snow age (//​snowdensdt//​) are general parameters (~ 0.1 and ~0.002). The snow's age increases by one every time step, but are weighted with age (0) for any new snow.
start/hype_model_description/hype_land.txt · Last modified: 2024/02/21 10:05 by cpers