ADDA. Analysis of daily data for the calibration of parameter "a"

Rainfall-runoff transformation parameters are one of the largest sources of uncertainty in hydrological forecast models. It is therefore advisable to carry out studies with historical data to evaluate its variation by basin and establish relationships with precipitation in previous days.


To calibrate these parameters, a specific formulation is used that will depend, in turn, on other parameters to be calibrated. Calibration will be based on unregulated basins with historical flow data.

For this reason, ADDA has been developed, with the general objective of carrying out historical studies to establish relationships between runoff parameters and antecedent precipitation.


The ultimate goal (all depending on the preceding rainfall) will be:

  • Pre-calibration of runoff parameters and definition of their variation ranges, which implies a significant improvement of the parameter self-calibration approach ( see general page on the subject  ), since it requires ranges as narrow as possible and based on studies.

  • Scenario definition based on pre-calibrated parameters. Even without real-time adjustments, calculations based on pre-calibration can already provide results with sufficient accuracy in many cases.