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Introduction

Introduction. G. Thirel and V. Andréassian. IAHS Hw15 . 22 July 2013. Modelling is like painting. Catchments are hyper-dynamic systems: they change continuously For the sake of our ‘portrating’, we need to make simplifying assumptions

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Introduction

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  1. Introduction G. Thirel and V. Andréassian IAHS Hw15 22 July 2013

  2. Modelling is like painting Catchments are hyper-dynamic systems: they change continuously For the sake of our ‘portrating’, we need to make simplifying assumptions The risk: that the simplifying hypotheses cause a catchment non-stationarity artefact

  3. Non stationarity makes the life of hydrologists miserable Identifying parameters is already not an easy task within the stationarity hypothesis… … it is much worse when changes which we have neglected turn out to have a significant impact on the calibration process

  4. Goal of this workshop To provide a factual diagnosis: describe / document the problem • based on common catchments • also on other datasets Can we agree on the problem? On how to assess it, numerically and graphically? Investigate solutions

  5. Workshop preparation group Guillaume Thirel Valérie Borrell-Estupina Sandra Ardoin-Bardin Julien Lerat Olga Semenova Francesco Laio

  6. Outline of thispresentation The dataset The calibration and evaluationprotocol Someresults IAHS Hw15 22 July 2013

  7. Outline of thispresentation The dataset The calibration and evaluationprotocol Someresults IAHS Hw15 22 July 2013

  8. Need for a dedicatedwebsite Possibility to download the data (password protected) • Description of the dataset for each basin • Description of the calibration and evaluationprotocol For defining the commonframework and for Providing the commondatabase Websiteaddress: http://non-stationarities.irstea.fr/ IAHS Hw15 22 July 2013

  9. The dataset 14 river basins showing non-stationarities IAHS Hw15 22 July 2013

  10. The dataset 14 river basins showing non-stationarities Basins sizes from 0.2 km² to 100,000km² Several types of non-stationarities encountered: Temperatureincrease Precipitation change or high variability Urbanization Forest cover modification Period: variable according to the considered basin IAHS Hw15 22 July 2013

  11. Which data? Data collectedfrommanypartners Variables: precipitation (P), temperature (T), potentialevapotranspiration (PE), discharge (Q). Whatweprovided: basin-wideaggregated values of P, T and PE Q at the outlet (repartition of altitude within the basin if available) Time step: daily IAHS Hw15 22 July 2013

  12. Temperatureincrease Allier Kamp The Kamp (622 km²), Allier (2267 km²), Durance (2170 km²) and Garonne (9980 km²) Rivers All located in Europe, impacted by snowmelt IAHS Hw15 22 July 2013 Durance Garonne

  13. The case of the Kamp River P Very large floods in 2002 IAHS Hw15 Q 22 July 2013 (Komma et al., 2007; Blöschl et al., 2008; Reszler et al., 2008)

  14. The case of the Allier River Impact on low flows CONSTRUCTION OF A DAM IN 1983 FOR SUSTAINING LOW FLOWS IAHS Hw15 22 July 2013

  15. Precipitation change or high variability Q Axe Creek Q The axe creek (237 km²) and the wimmera River (2000 km²) Millenium drought in Australia (1997-2008) IAHS Hw15 22 July 2013 Wimmera River

  16. Precipitation change or high variability P Q Decrease in rainfall and deep water recharge betweenbefore 1970 and after 1971 The bani River (100,000 km²) IAHS Hw15 22 July 2013

  17. Precipitation change or high variability The Flinders River The Gilbert and Flinders Rivers (around 1900 km²) Arid catchments under cyclonic heavy rainfall influence. Major flood in 2002. IAHS Hw15 22 July 2013

  18. Urbanization Percentage of urbanization The ferson (134 km²) and blackberry creeks (182 km²) Located in the USA The urbanization modifies the hydrologicalresponse IAHS Hw15 22 July 2013

  19. Forest cover modification The fernow(0,2 km²) and Mörrumsån (97 km²) Rivers and the Real Collobrier (1,4 km²) The FernowExperimentalwatershed: forest cut of the lower part of the basin, then forest cut of the upper part of the basin, then plantation of firtrees. The Mörrumsån River: a severe storm (Gudrun), led to loss of forest in January 2005. The Real Collobrier: forest fire in August 1990. IAHS Hw15 22 July 2013

  20. The dataset

  21. Outline of thispresentation The dataset The calibration and evaluationprotocol Someresults IAHS Hw15 22 July 2013

  22. The protocol Change A common calibration and evaluationframework Common calibration / evaluation periods Common minimum set of metrics Possibility that I produce a set of metrics and plots for the modellers (providing that they sent to me their simulations) Modellers are free to do more! IAHS Hw15 22 July 2013 P3 P1 P2 P4 P5 Time Warm-up Complete period

  23. The protocol Change Level 1: the beginnerlevel Calibration has to be done on the “Complete period” or the model does not need calibration Models are run on the “Complete period” Evaluation is done on the “Complete period” + P1 to P5 IAHS Hw15 22 July 2013 P3 P1 P2 P4 P5 Time Warm-up Complete period

  24. The protocol Change Level 2: the normal level Calibration has to be done on each pre-defined sub-period P1 to P5 Models are run on the “Complete period” for each calibration Evaluation is done on the “Complete period” + P1 to P5 IAHS Hw15 22 July 2013 P3 P1 P2 P4 P5 Time Warm-up Complete period

  25. The protocol Level 3: the expert level The modellers found that their model failed at level 2 to deal with non-stationarities or could do better. They want to try to solve this issue, or at least to try to test solutions that could solve this issue. -> all solutions are allowed. Failing is fine, since it allows to discard a solution. IAHS Hw15 22 July 2013

  26. The protocol The metrics Participants were asked to produce the following statistics on each sub-period: NSE and NSE on low flows (i.e. using 1/Q+ε instead of Q) Bias (Qsim/Qobs) Discharge quantiles: Q95, Q85, Q15 and Q05 Frequency of low flows (i.e. when Q<5% of mean Qobs) IAHS Hw15 22 July 2013

  27. The protocol Participants were asked to produce the following statistics on each sub-period: • NSE and NSE on low flows (i.e. using 1/Q+ε instead of Q) + their decomposition • Bias (Qsim/Qobs) • Discharge quantiles: Q95, Q85, Q15 and Q05 • Frequency of low flows (i.e. when Q<5% of mean Qobs) • KGE and its decomposition • Nash and bias on sliding windows • Flow regime • Ranked discharges The metrics IAHS Hw15 22 July 2013

  28. The protocol Six curves: one for each calibration The criterion value Six values: one for each evaluation period The criterion value Six lines: one for each evaluation period Six columns: one for each calibration Two different ways of showing the same thing The graphs Used for the bias, the Nash criteria, the KGE, and their decompositions For the quantiles and the frequency of low flows, the observed value is added IAHS Hw15 22 July 2013

  29. The protocol The graphs Extension of some graphs for a 1-year frequency evaluation IAHS Hw15 22 July 2013

  30. The protocol The graphs The discharges regimes and the ranked discharges -> one graph for each evaluation period IAHS Hw15 22 July 2013

  31. Blue values indicate that this model has a higher criterion The protocol Red values indicate that this model has a higher criterion Mod 1 Mod 2 Blue values indicate that this model has a higher criterion A line compares each calibration on a single evaluation period Mod 1 Not values, but differences between the criteria of two models Over-estimation from model on top Δ Under-estimation from the model on top A column compares a single calibration on each evaluation period Mod 2 Red values indicate that this model has a higher criterion THE COMPARISONS BETWEEN MODELS IAHS Hw15 22 July 2013

  32. Outline of thispresentation The dataset The calibration and evaluationprotocol Someresults IAHS Hw15 22 July 2013

  33. List of models used for the workshop 1k-DHM, AWBM, CLSM, COSERO, ECOMAG, GARDENIA, GR4J, GR5J, HBV, HYDROGEOIS, HYPE, HyMod, IHACRES, MISO, MORDOR, MORDOR6, SAFRAN-ISBA-MODCOU, SimHyd, SpringSim, TOPMODEL, Xinanjiang,… IAHS Hw15 22 July 2013

  34. Briefpresentation of someresultsfrom people whoparticipated but could not come GARDENIA: D. Thiéry, BRGM, France COSERO: H. Kling, Austria SpringSim: A. Ramchurn, Australia IAHS Hw15 22 July 2013

  35. GARDENIA USED BY: Dominique Thiery (d.thiery@brgm.fr, BRGM, France) Lumped model withslow compo- nentsreservoirs Can takeintoaccountaquifer levelmeasurements (not used here) 4 to 6 parameters Calibration metrics: MSE(sqrt(Q))+5%(Qsim-Qobs) Ranon 11 basins Ref: Thiéry, D. (2010) ReservoirModels in Hydrogeology, in MathematicalModels, Volume 2(edJ.-M. Tanguy), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9781118557853.ch13 IAHS Hw15 22 July 2013

  36. GARDENIA Bani USED BY: Dominique Thiery (d.thiery@brgm.fr, BRGM, France) Regime change from 1971 Low bias on calibration periods, but high bias on contrasted periods. The calibration on the complete period allows an « intermediary » solution but does not prevent from biased simulations. Calibrations on dryer periods gave higher soil reservoir capacities: the model tries to allow more evapotranspiration for compensating the lower Q. IAHS Hw15 22 July 2013

  37. GARDENIA USED BY: Dominique Thiery (d.thiery@brgm.fr, BRGM, France) Wimmera Millenium Drought High bias on contrastedperiods. Calibrations on dryerperiods gave highersoilreservoircapacities: try of the model to allow more evapotranspiration for compensating the lower Q. IAHS Hw15 22 July 2013

  38. COSERO USED BY: Harald Kling (harald.kling@poyry.com, Pöyry Energy GmbH, Austria) Continuous, semi-distributed rainfall-runoff model. • Snow processes • Soil moisture accounting (HBV-type) • Surface-flow, inter-flow, base-flow (linear reservoirs) • Nachtnebel et al. (1993) IAHS Hw15 22 July 2013

  39. COSERO USED BY: Harald Kling (harald.kling@poyry.com, Pöyry Energy GmbH, Austria) Objective function: KGE on Q. Ran on 11 basins (i.e. all except US basins). Dam module (affects low flows) added for the Allier River. Riparian zone (affects evaporation) added for Australian rivers. IAHS Hw15 22 July 2013

  40. COSERO USED BY: Harald Kling (harald.kling@poyry.com, Pöyry Energy GmbH, Austria) Allier New dam built in 1983 IAHS Hw15 22 July 2013

  41. COSERO USED BY: Harald Kling (harald.kling@poyry.com, Pöyry Energy GmbH, Austria) Wimmera Millenium Drought IAHS Hw15 22 July 2013 GR4J COSERO Similar behaviour: clear over-estimation for the Millenium Drought Difference: no clear under-estimation of wet years for Cosero when calibrated on dry years

  42. SpringSIM New model, implemented to deal specificallywith incorporation of long termdroughts in the routine response to rainfall/evaporation of rainfall-runoffmodels 12 parameters USED BY: AvijeetRamchurn (a.ramchurn@bom.gov.au, Bureau of Meteorology, Australia) IAHS Hw15 22 July 2013

  43. SpringSIM USED BY: AvijeetRamchurn (a.ramchurn@bom.gov.au, Bureau of Meteorology, Australia) IAHS Hw15 22 July 2013

  44. SpringSIM Bani Good simulations of the water volume USED BY: AvijeetRamchurn (a.ramchurn@bom.gov.au, Bureau of Meteorology, Australia) IAHS Hw15 22 July 2013

  45. SpringSIM Bani Wet Dry Lowbias in contrastedperiods USED BY: AvijeetRamchurn (a.ramchurn@bom.gov.au, Bureau of Meteorology, Australia) IAHS Hw15 22 July 2013 Wet Dry

  46. Thank you!

  47. The protocol THE COMPARISONS BETWEEN MODELS Mod 1 Mod 2 Comparisons with observations Over-estimation from model on top Δ Under-estimation from the model on top Comparisons between the models Mod 1 Mod 2

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