Interception

Interception storage is represented by a bucket. The storage is filled by liquid and solid precipitation and spills if the storage is full.

Interception from upper interception storage

Interception by upper interception storage \(INT_{upper}\) at time step \(t\) (mm \(\Delta t^{-1}\)):

\[\begin{split}INT_{upper}=\left\{\begin{array}{lr} PREC \cdot (1 - c_{throughfall}) & PREC \cdot (1 - c_{throughfall}) \leq S_{tot-int-upper} - S_{int-upper} \\ S_{tot-int-upper} - S_{int-upper} & PREC \cdot (1 - c_{throughfall}) > S_{tot-int-upper} - S_{int-upper} \end{array}\right.\end{split}\]

where \(PREC\) is precipitation (mm \(\Delta t^{-1}\)), \(c_{throughfall}\) is the throughfall coeffcient of the canopy, \(S_{int-upper}\) is the storage volume of the upper interception storage at time step \(t\) (mm) and \(S_{tot-int-upper}\) is the available storage volume of the upper interception storage (mm).

Interception from lower interception storage

Interception by lower interception storage \(INT_{lower}\) at time step \(t\) (mm \(\Delta t^{-1}\)):

\[\begin{split}INT_{lower}=\left\{\begin{array}{lr} PREC & PREC \leq S_{tot-int-lower} - S_{int-lower} \\ S_{tot-int-lower} - S_{int-lower} & PREC > S_{tot-int-lower} - S_{int-lower} \end{array}\right.\end{split}\]

where \(PREC\) is precipitation (mm \(\Delta t^{-1}\)), \(S_{int-lower}\) is the storage volume of the lower interception storage at time step \(t\) (mm) and \(S_{tot-int-lower}\) is the available storage volume of the lower interception storage (mm).