Projecting climate change impacts on water resources in Switzerland

Transcription

1 Projecting climate change impacts on water resources in Switzerland B.Schaefli Manuel Hulliger

2 INPUT Process OUTPUT Dischma Manuel Hulliger

3 Annual / mean discharge Simulations from 4 different s / 3 different groups all wrong? Year Manuel Hulliger

4 Current water resources? 4

5 Current water resources? Precip Runoff Net ice melt Transpiration Evaporation Ground water 5

6 Role of (un-)certainty ranges Present day uncertainty Change prediction impossible Probability distribution Uncertainty for scenario Target variable (e.g. average streamflow)

7 Role of natural variability Significance of changes? Probability distribution Present day natural variability Scenario variability Target variable (e.g. average streamflow)

8 Philograf

9 Climate change chain Global scale Regional scale Emission scenario Global climate Global climate Regional climate Local scale Precip. Regional climate Temp. Time series Landuse Hydro.-hydraul. generator Land use Stream- flow Sediments Ecosystem Management 9

10 Model development Calibration period Observed meteo, reanalysis data Global scale Regional scale Development/ calibration Emission scenario Local scale Global climate Precip. Temp. Global climate Regional climate Regional climate Time series Validation Landuse Land use Streamflow Hydro.-hydraul. Sediments generator Ecosystem Management Observed state Ecosystem quality Water release Electricity production Model quality /uncertainty Natural variability

11 Model development Control simulation Calibration period Control period Observed meteo, reanalysis data Simulated meteo Global scale Regional scale Development/ calibration Emission scenario Local scale Global climate Precip. Temp. Global climate Regional climate Regional climate Time series Validation Landuse Land use Streamflow Hydro.-hydraul. Sediments generator Ecosystem Management Observed state Ecosystem quality Water Electricity Control state release production Model quality /uncertainty Natural variability

12 Model development Control simulation Scenario simulation Calibration period Control period Scenario period Observed meteo, reanalysis data Simulated meteo Simulated meteo data Global scale Regional scale Development/ calibration Emission scenario Local scale Global climate Precip. Temp. Global climate Regional climate Regional climate Time series Validation Landuse Land use Streamflow Hydro.-hydraul. Sediments generator Ecosystem Management Observed state Ecosystem quality Water Electricity Control state release production Scenario state Model quality /uncertainty Natural variability Change assessment Significance of change

13 Uncertain changes Can we make useful climate change predictions? Answer 1: No because Scenario production with calibrated s & simulated meteorology bettina.schaefli@unil.ch 13

14 Uncertain changes Can we make useful climate change predictions? Answer 2: No because Present day Prediction impossible Probability Future scenario Target variable (e.g. hydropower offer) 14

15 Uncertain changes Can we make useful climate change predictions? Answer 3: No because Baseline prediction uncertainty 15

16 Certain changes! Can we make useful climate change predictions? Answer 4: Yes but only for certain aspects 16

17 Climate change impact on water resources CCHYDRO (source: «report «CCHydro Veredelung») Jérémy Bierer

18 2.5% glacier covered Mean net ice loss: m/yr = 0.7 km 3 /yr ( ) Fischer et al., 2014, 2015

19 Moment of peak water? Ongoing estimation of all glacier volumes with ice penetrating radar

20 Future water temperatures? Gallice et al., 2015 (c) Adrian Michael

21 Future sediment loads? Several ongoing projects SCCER-SoE NRP70 SedFate (SNF Sinergia) (c) M. Funk

22 Quantification of extremes Stochastic tools for local-scale meteo scenarios New tools to assess chain reliability Understand vulnerability & risk reduction tools 22

23 Focus on vulnerability? Quantify water resources vulnerability Catalogue of climate-related critical events Vulnerability assessment via scenarios from observed data Assessment of spatial co-variations of water resources Real-time forecasting to decrease risks 23

24 Conclusion - challenges Water resources quantification Better quantification of baseline scenarios (uncertainty) Experimental catchments! Prediction of extremes Focus on meteo & scenario generators Limits of predictability for selected case studies Shift to vulnerability assessment? bettina.schaefli@unil.ch 24

25 F. Palazzi Scenarios Uncertainty Vulnerability Schaefli, B.: Projecting hydropower production under future climates: a guide for decision-makers and ers (..), WIREs Water, bettina.schaefli@unil.ch 25