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# Evaporation

The volume of water lost to evaporation on a given day is calculated:

          $$V\_{evap}=10\*\eta*E\_o*SA$$                                                           8:1.2.9

where $$V\_{evap}$$ is the volume of water removed from the water body by evaporation during the day (m$$^3$$ H$$\_2$$O), $$\eta$$ is an evaporation coefficient (0.6), $$E\_o$$ is the potential evapotranspiration for a given day (mm H$$\_2$$O), and $$SA$$ is the surface area of the water body (ha).