Model relating rainfall timing and intensity to surface water area.


EQUATIONS


CHANGE IN SOIL WATER VOLUME

VD = QD QDG QDI RD DW

CHANGE IN SURFACE WATER VOLUME


VW = RDW + RW + QDI


- E QW


RAINFALL ON DRYLAND AREAS
RD = IAD

RAINFALL SWITCHED TO SURFACE WATER
FROM DRY LAND WHEN DRY LAND SATURATED
RDW = C4 {( I x AD) VDmax VD}


RAINFALL ON SURFACE WATER

RW = IAW

GROUND WATER FLOW TO SEA
 hD
QDG = T B C1
 dD

INTERFLOW BETWEEN SOIL AND
SURFACE STORAGE
 hD hW
QDI = k p h hs C2
 dW

EVAPOTRANSPIRATION FROM SURFACE
WATER


Ew = 0.75 P AW S C5
W e W 5


AREA OF LAND SURFACE
COVERED BY WATER
AW = fVW (Volume-Area curve)

DRY LAND AREA
AD = AT A

EVAPOTRANSPIRATION FROM SOIL


ED = 0.75


 VD
Pe VDmax D S


RUNOFF FROM SURFACE WATER
AREAS


 1.49
QW= n


 AW
h 5/3 a(wW
 w Wmax


(sin 9)1/2 C3


Figure 14.