eflowcalc.th1

eflowcalc.th1(flows, datetimes, hydro_years, drainage_area)

Timing of annual maximum flow.

Calculation Details

Determine the day of the year (i.e. number) in the Julian calendar where the flow is maximal in each hydrological year in the daily flow record. Map these dates onto a circular scale as angles in radians. Determine the x and y components of these angles (i.e. cosine, and sine, respectively). Compute the mean of the x and y components separately. Use these means to compute the corresponding mean angle, and convert this mean angle back to a day of the year in the Julian calendar (using the arc-tangent).