• Aucun résultat trouvé

Introduction of a SWE-SCA hysteresis in a degree-day snow model for rainfall-runoff modelling

N/A
N/A
Protected

Academic year: 2021

Partager "Introduction of a SWE-SCA hysteresis in a degree-day snow model for rainfall-runoff modelling"

Copied!
2
0
0

Texte intégral

(1)

HAL Id: hal-02608249

https://hal.inrae.fr/hal-02608249

Submitted on 16 May 2020

HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.

L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Introduction of a SWE-SCA hysteresis in a degree-day snow model for rainfall-runoff modelling

P. Riboust, Guillaume Thirel, N. Le Moine, Pierre Ribstein

To cite this version:

P. Riboust, Guillaume Thirel, N. Le Moine, Pierre Ribstein. Introduction of a SWE-SCA hysteresis in a degree-day snow model for rainfall-runoff modelling. EGU General Assembly, Apr 2018, Vienna, Austria. pp.1, 2018. �hal-02608249�

(2)

Introduction of a SWE-SCA hysteresis in a degree-day snow model for rainfall-runoff modelling

Snow models used for rainfall-runoff (RR) modelling are often calibrated jointly with a hydrological model against discharge (Q) only, leading to

poor snow simulation.

Drawbacks:

- Optimisation can force snow model to compensate RR model flaws - Assimilation of snow data is very difficult

Here (Riboust et al., 2018), we implement a SWE-SCA linear hysteresis (LH) and use MODIS SCA data to improve the snowpack modelling.

Fig. 1: Heterogeneity of the snowpack during melt at Edelbodenalm,

Austria (Parajka et al., 2012)

Riboust Philippe 1,2 , Thirel Guillaume 1 , Le Moine Nicolas 2 & Ribstein Pierre 2

1: HYDRO - HYCAR – Irstea, Antony, France 2: UPMC Univ. Paris 06 – Sorbonne Universités, Paris, France

guillaume.thirel@irstea.fr

1. Rationale

2. The CemaNeige snow model Characteristics:

- Degree-day

- 5 altitude bands

- Coupled to GR4J RR model - 2 parameters to calibrate

- With LH: 2 more parameters

Variables (extrap. with altitude):

- Mean air temperature - Precipitation

P T

mean

Snow

Snow

Stock G

Melt

Max=0°C

Snow thermal state

  cT

f eT

G

Kf

Rain

Inputs

Outputs

3. Experimental set up

277 natural snowy basins

- Periods: 2000-2010 divided into 2 calibration/validation periods

- All results presented on valid. Periods here - Criterion: KGE’ (Kling et al., 2012) on Q (and

SCA in some cases, see Eq. 1)

SWE (mm) SWE (mm)

Fig. 3: The SWE-SCA LH (right) represents the heterogenous spatial

melt of snow at the basin scale

Solid precip.

(mm)

4. Impact of the linear hysteresis and sensitivity to SCA weights in the objective function

Model Q weighting α β 1 … 5 weighting for altitude bands

CemaNeige reference (C Q) 1 0

CemaNeige SCA (C Q SCA) 0.75 0.05 x 5 CemaNeige linear hysteresis (LH*) 0.75 0.05 x 5

Coron, L., Thirel, G., Delaigue, O., Perrin, C., Andréassian, V., 2017: The Suite of Lumped GR Hydrological Models in an R package, Environmental Modelling & Software Kling, H., M. Fuchs, and M. Paulin (2012), Runoff conditions in the upper Danube basin under an ensemble of climate change scenarios. Journal of Hydrology

Parajka, J., Haas, P., Kirnbauer, R., Jansa, J., Blöschl, G., 2012. Potential of time-lapse photography of snow for hydrological purposes at the small catchment scale. Hydrol. Process.

Riboust, P., Thirel, G., Le Moine, N., and Ribstein, P.: Revisiting a simple degree-day model for integrating satellite data: implementation of SWE-SCA hystereses. Journal of Hydrology and Hydrodynamics, DOI:

10.2478/johh-2018-0004, accepted, 2018

Fig. 5 shows that:

- Calibrating CemaNeige with Q and SCA improves SCA but deteriorates Q compared to ref.

- Using in addition a LH improves SCA even more with similar Q performance compared to ref.

Fig. 6 shows that 75% of weight on Q (and 25% on SCA) seems a reasonable compromise

Fig. 4: Study area Fig. 2: The CemaNeige model

7. References

Fig. 5: Q and SCA performances for the experiments of Tab. 1 (letters on the right are results of Friedman test)

Tab. 1: Experimentation setup for Fig. 5

Fig. 6: Q and SCA performances with differentQ and SCA weights

Fig. 8: CemaNeige melt factor (mm/ ° C/d)

when coupled to HBV or GR4J with

original CemaNeige or linear hysteresis

Eq. 1: Objective function

Fig. 7: Improvement of Q and SCA for the River Durance with the new CemaNeige version (LH*

exp.)

5. The linear hysteresis improves the model robustness 6. Conclusions and perspectives

1960-1970 1970-1980 1980-1990

Fig. 9: Performance of original and new

CemaNeige versions on independent past periods (with GR4J)

The implementation of LH in CemaNeige improves its parameters

stability when coupled to another RR model (HBV, Fig. 8) and improves the performances on Q on contrasted and independent periods (Fig. 9).

The newly-implemented SWE-SCA LH improves the quality of SCA without

deteriorating Q. Results suggest that:

- Use of additional MODIS SCA data for calibration or data assimilation is now allowed

- Climate change applications are facilitated due to more stable parameters and better performances on past periods

This new CemaNeige version will be available shortly in the airGR R package (Coron et al., 2017).

Original formulation New formulation

𝐶𝑟𝑖𝑡 = 𝛼 𝐾𝐺𝐸 𝑄 + 𝛽 𝑖 𝐾𝐺𝐸′(𝑆𝐶𝐴 𝑖 )

5

𝑖=1

Références

Documents relatifs

Considering Sherbrooke-A snow depth data to be representative, it becomes obvious that using SIRENE data did not provide accurate thickness simulations Table 4; however, results

Equilibrium results of the link model using the default parameters in terms of (a) flows at each time period, (b) costs per mode, (c) cumulative travellers and

Even the sensitivity is much bigger then the one found in L or C band, density impact is quite complex, because of approxi- mately equal contribution of ground-snow dielectric

and spectrometer), the precision XY stage, the variable light source, the cutting device, the sample transportation system, and the temperature controlled storage

To identify precisely the transport mechanisms during debris avalanches, we examined morphometric (fractal dimension and circularity), grain size, and exoscopic characteristics of

A new equation of state for pure water substance was applied to two problems associated with steam turbine cycle calculations, to evaluate the advantages of

L’humour se situe à la fois dans l’origine des sons – le chant sans transformation, qui est un matériau sonore très rare en électroacoustique, est ici perçu comme

à prendre acte de l’universalité démocratique des affects, mais en réintroduisant une qualification antisocratique de la gamme émotive. À l’opposé de cette logique