(c) You have a two store catchment model that includes baseflow, evapotranspirat
ID: 116951 • Letter: #
Question
(c) You have a two store catchment model that includes baseflow, evapotranspiration and surface runoff due to saturation excess (see diagram below). The following information is available The initial soil water storage, S, (i.e. at the start of the day) is 100mm. * The soil water storage capacity, Smax, is 200mm. 10% of the catchment is saturated. You may assume that the only event runoff process is saturation excess runoff and the saturated area does not change over the day e precipitation for the day is 20mm. The potential evapotranspiration (PET) for the day is 6 mm. · The actual evapotranspiration can be calculated as AET = PET*S/Smax *The field capacity (F) is 100mm and drainage in mm from the soil storage to the groundwater store can be calculated as (S-F) *0.20 seflow for the day is 0.5mm. The basetlow Tor the day is 0.5mm The initial groundwater storage is 25mm. The catchment area is 10km * i. Estimate the actual evapotranspiration for the day (1 marks) ii. Estimate the surface runoff depth for the day (2 marks) iii. Estimate the total runoff volume for the day (2 marks) iv. Estimate the soil water storage and the groundwater storage at the end of the day (4 marks) ET PET S/Smax Smax Si (S-.0.20Explanation / Answer
Actual evapotranspiration = PET *S/S max
PET =Potential evapotranspiration = 6 mm
S= Initial soil water storage = 100 mm
Smax = soil water storage capacity = 200 mm
AET = 6* 100/200
AET = 3 mm
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.