projection under the RCP 8.5 scenario simulated with the MIROC5 model reveals a
strengthening of the tendency, with another 50% reduction of the actual average
August discharge, but a more worrisome increase of the low-flow period, which may
extend until the end of October in the future and start 1 month earlier. This drastic
mutation of the hydrological regime may be manageable considering the projected
significant increase of the January and February discharges but reveals the crucial
need for the elaboration of adaptation strategies for water resources management.
This work is a first analysis based on a careful selection of only one climate
projection that best mimics the low frequency of the rainfall signal. It will need to be
strengthened in the future by a more thorough analysis of more climate projections
with the definition of a pertinent and not redundant ensemble of climate projections.
The more progress made in climate projections, the more sensitive the results will be
to uncertainties due to model errors and especially to processes controlling surface
and subsurface exchanges, i.e. aquifer recharge processes as well as river–aquifer
exchanges. The PIREN-Seine will therefore continue to dedicate a significant part of
its research resources to those key scientific questions.
Acknowledgements This study is a contribution to the PIREN-Seine research programme (www.
piren-seine.fr), which belongs to the Zone Atelier Seine part of the international Long-Term SocioEcological Research (LTSER) network.
References
1. Flipo N, Lestel L, Labadie P et al (2020) Trajectories of the Seine River basin. In: Flipo N,
Labadie P, Lestel L (eds) The Seine River basin. Handbook of environmental chemistry.
Springer, Cham. https://doi.org/10.1007/698_2019_437
2. Billen G, Garnier J, Mouchel J-M, Silvestre M (2007) The Seine system: introduction to a
multidisciplinary approach of the functioning of a regional river system. Sci Total Environ
375:1–12
3. Guillocheau F, Robin C, Allemand P et al (2000) Meso-Cenozoic geodynamic evolution of the
Paris Basin: 3D stratigraphic constraints. Geodin Acta 13:189–245. https://doi.org/10.1080/
09853111.2000.11105372
4. Meehl GA, Covey C, Delworth T et al (2007) The WCRP CMIP3 multimodel dataset: a new
era in climate change research. Bull Am Meteorol Soc 88:1383–1394. https://doi.org/10.1175/
BAMS-88-9-1383
5. Taylor KE, Stouffer RJ, Meehl GA (2012) An overview of CMIP5 and the experiment design.
Bull Am Meteorol Soc 93:485–498. https://doi.org/10.1175/BAMS-D-11-00094.1
6. Dayon G, Boé J, Martin E, Gailhard J (2018) Impacts of climate change on the hydrological
cycle over France and associated uncertainties. C R Geosci 350:141–153. https://doi.org/10.
1016/j.crte.2018.03.001
7. Déqué M, Somot S, Sanchez-Gomez E et al (2012) The spread amongst ENSEMBLES
regional scenarios: regional climate models, driving general circulation models and
interannual variability. Climate Dynam 38:951–964. https://doi.org/10.1007/s00382-0111053-x
8. Hattermann FF, Krysanova V, Gosling SN et al (2017) Cross-scale intercomparison of climate
change impacts simulated by regional and global hydrological models in eleven large river
basins. Clim Change 141:561–576. https://doi.org/10.1007/s10584-016-1829-4
Pluri-annual Water Budget on the Seine Basin: Past, Current and Future Trends
83
strengthening of the tendency, with another 50% reduction of the actual average
August discharge, but a more worrisome increase of the low-flow period, which may
extend until the end of October in the future and start 1 month earlier. This drastic
mutation of the hydrological regime may be manageable considering the projected
significant increase of the January and February discharges but reveals the crucial
need for the elaboration of adaptation strategies for water resources management.
This work is a first analysis based on a careful selection of only one climate
projection that best mimics the low frequency of the rainfall signal. It will need to be
strengthened in the future by a more thorough analysis of more climate projections
with the definition of a pertinent and not redundant ensemble of climate projections.
The more progress made in climate projections, the more sensitive the results will be
to uncertainties due to model errors and especially to processes controlling surface
and subsurface exchanges, i.e. aquifer recharge processes as well as river–aquifer
exchanges. The PIREN-Seine will therefore continue to dedicate a significant part of
its research resources to those key scientific questions.
Acknowledgements This study is a contribution to the PIREN-Seine research programme (www.
piren-seine.fr), which belongs to the Zone Atelier Seine part of the international Long-Term SocioEcological Research (LTSER) network.
References
1. Flipo N, Lestel L, Labadie P et al (2020) Trajectories of the Seine River basin. In: Flipo N,
Labadie P, Lestel L (eds) The Seine River basin. Handbook of environmental chemistry.
Springer, Cham. https://doi.org/10.1007/698_2019_437
2. Billen G, Garnier J, Mouchel J-M, Silvestre M (2007) The Seine system: introduction to a
multidisciplinary approach of the functioning of a regional river system. Sci Total Environ
375:1–12
3. Guillocheau F, Robin C, Allemand P et al (2000) Meso-Cenozoic geodynamic evolution of the
Paris Basin: 3D stratigraphic constraints. Geodin Acta 13:189–245. https://doi.org/10.1080/
09853111.2000.11105372
4. Meehl GA, Covey C, Delworth T et al (2007) The WCRP CMIP3 multimodel dataset: a new
era in climate change research. Bull Am Meteorol Soc 88:1383–1394. https://doi.org/10.1175/
BAMS-88-9-1383
5. Taylor KE, Stouffer RJ, Meehl GA (2012) An overview of CMIP5 and the experiment design.
Bull Am Meteorol Soc 93:485–498. https://doi.org/10.1175/BAMS-D-11-00094.1
6. Dayon G, Boé J, Martin E, Gailhard J (2018) Impacts of climate change on the hydrological
cycle over France and associated uncertainties. C R Geosci 350:141–153. https://doi.org/10.
1016/j.crte.2018.03.001
7. Déqué M, Somot S, Sanchez-Gomez E et al (2012) The spread amongst ENSEMBLES
regional scenarios: regional climate models, driving general circulation models and
interannual variability. Climate Dynam 38:951–964. https://doi.org/10.1007/s00382-0111053-x
8. Hattermann FF, Krysanova V, Gosling SN et al (2017) Cross-scale intercomparison of climate
change impacts simulated by regional and global hydrological models in eleven large river
basins. Clim Change 141:561–576. https://doi.org/10.1007/s10584-016-1829-4
Pluri-annual Water Budget on the Seine Basin: Past, Current and Future Trends
83