Assessment of forecast uncertainty with OTAMIN

OTAMIN is designed to automatically associate confidence intervals to hydrologic and hydraulic forecasts obtained from diverse deterministic models that are used for real-time applications. This tool was developed thanks to the PhD work of Bourgin (2014) at INRAE.

Forecasts uncertainty is estimated using the method QUOIQUE (also developed by Bourgin, 2014), which aims at describing relative errors behavior based on past observations and simulations. Errors are classified regarding the range of simulated values and the forecast lead-time, which constitutes an easy tool to anticipate future errors knowing forecasts and lead-time. QUOIQUE is based on the hypothesis that errors are temporally stable.

The architecture of OTAMIN

OTAMIN is divided into three tools:

  • An analysis tool that helps the user to evaluate the method and the uncertainty temporal stability thanks to a calibration-validation process.
  • A calibration tool that creates error abacus which are then used for real-time uncertainties assessment.
  • A real-time tool that provides uncertainties applied to real-time forecasts using the abacus created during the calibration (see Figure 1).


Figure 1: Confidence intervals for a forecast

Software environment needed
R software (version >= 3.2.1) is required to use the OTAMIN software. It is freely available.
The GRP software runs in Windows or Linux environment.


The OTAMIN software is used by the Vigicrues network, an information service on the flood risk for the main rivers in France (with the use of the national hydrometric network, and observation and forecast data produced by Météo-France). It is also used by various water managers and in the field of research and teaching.

How to access the software?

The OTAMIN software was developed mainly through a collaboration with the Central Hydrometeorological and Flood Forecasting Service (SCHAPI) of the Ministry in charge of the environment.
Contact @ INRAE: François Bourgin