The results of applying the ratio of the seasonal annual maximum rainfall for a given duration to the annual maximum rainfall for the same duration
Usage
SCF(SAAR, duration)
Value
A data.frame of one row and two columns: SCFSummer and SCFWinter.
Arguments
SAAR
standardised average annual rainfall. Numeric
duration
duration in hours. Numeric
Author
Anthony Hammond
Details
The SCF and its use is detailed in R&D Technical Report FD1913/TR - Revitalisation of the FSR/FEH rainfall runoff method (2005). The ReFH model has a design rainfall profile included for winter and summer but the depth duration frequency (DDF) model is calibrated on annual maximum peaks as opposed to seasonal peaks. The SCF is necessary to convert the DDF estimate to a seasonal one. Similarly, the DDF model is calibrated on point rainfall and the area reduction factor converts it to a catchment rainfall for use with a rainfall runoff model such as ReFH (see details of the ReFH function). The final depth, therefore, is; Depth = DDFdepth x ARF x SCF. Note that the SCF function (as detailed in FEH volume 2) was derived for durations of up to one day.