Motivation and Overview of Hydrological Ensemble Post-processing

  • Thomas M. Hopson
  • Andy WoodEmail author
  • Albrecht H. Weerts
Reference work entry


In this introduction to this chapter on hydrologic post-processing, we discuss the different but complementary directives that the “art” of post-processing must satisfy: the particular directive defined by specific applications and user needs; versus the general directive of making any ensemble member indistinguishable from the observations. Also discussed are the features of hydrologic post-processing that are similar and separate from meteorological post-processing, providing a tie-in to early chapters in this handbook. We also provide an overview of the different aspects the practitioner should keep in mind when developing and implementing algorithms to adequately “correct and calibrate” ensemble forecasts: when forecast uncertainties should be characterized separately versus maintaining a “lumped” approach; additional aspects of hydrological ensembles that need to be maintained to satisfy additional user requirements, such as temporal covariability in the ensemble time series, an overview of the different post-processing approaches being used in practice and in the literature, and concluding with a brief overview of more specific requirements and challenges implicit in the “art” of post-processing.


Post-processing Conditional forecast Regression Estimation Uncertainty Systematic error Bias correction Streamflow forecast Hydrologic modeling Covariance 


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Thomas M. Hopson
    • 1
  • Andy Wood
    • 2
  • Albrecht H. Weerts
    • 3
    • 4
  1. 1.Research Applications LaboratoryNational Center for Atmospheric ResearchBoulderUSA
  2. 2.National Center for Atmospheric ResearchBoulderUSA
  3. 3.Operational Water Management, Inland Water Systems, DeltaresDelftThe Netherlands
  4. 4.Hydrology and Quantitative Water Management Group, Wageningen University and ResearchWageningenThe Netherlands

Section editors and affiliations

  • Andy Wood
    • 1
  • Thomas Hopson
    • 2
  1. 1.National Center for Atmospheric ResearchBoulderUSA
  2. 2.Research Applications Laboratory, National Center for Atmospheric ResearchColoradoUSA

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