New Approaches to Adaptive Water Management under Uncertainty Elbe Basin: Looking at potential Futures

Transcription

1 New Approaches to Adaptive Water Management under Uncertainty Elbe Basin: Looking at potential Futures 1 Valentina Krysanova, Cornelia Hesse, Fred Hattermann, Shaochun Huang, Marta Martinkova, Romana Koskova, Sona Nemeckova

2 How to look at potential futures? Investigating historical trends in climate characteristics, water discharge, etc.; Developing scenarios of changes in climate & land use and investigating impacts on water availability, extreme events (floods and droughts), water quality etc.; Comparing water availability and water demand for future conditions (studying water stress). 2

3 Precipitation trend for Germany Average annual precipitation Trend in precipitation: Data: Gerstengarbe & Werner, PIK Potsdam

4 Trend in Dry Spells in the Elbe basin, Paper: Krysanova, Vetter & Hattermann, HSJ 2008

5 Jahresmitteltemperaturen [ C] Climate scenario: 100 realizations, statistical model STAR (PIK) Observed period observed temperature Trend in temperature Scenario period Scenario realizations Number of realizations In blue: mean % included 50 % included median of ralizations mean Precipitation in [mm]

6 Number of realizations In blue: mean % included 50 % included median of ralizations mean Change in precipitation and river discharge of the Elbe, 100 realisations of climate scenario (models STAR and SWIM) Precipitation in [mm] 6 Paper: Hattermann, Krysanova Abfluss am Elbepegel Neu Darchau in m 3 s 1 Elbe Runoff at Neu Darchau [m 3 s 1 ] simulated mean % of the realizations % of the realizations J F M A M J J A S O N D Month Monat et al

7 Land use change impact for the Rhin catchment discharge NO3N decrease % increase PO4P bank conversion of agricultural land within 50 m around rivers and lakes to extensive grassland conversion forest conversion of all forested areas (34% of the whole catchment) to deciduous forests crop types change of crop types needing the highest fertilizer amounts (rape, beet and maize) to winter wheat reduction fertilizer sewage maintaining crop types composition but reducing crop specific fertilisation by 20% reducing the N emissions of all sewage treatment plants by 10% and the P emissions by 20% 7 Paper: Hesse, Krysanova, Hattermann, EcMod, 2008

8 Land use change impact assessment for the Unstrut basin % 92.63% 80.00% 60.00% 40.00% 20.00% 0.00% 20.00% 19.16% 5.27% 25.44% 6.01% 2.93% 2.87% 5.69% 40.74% 40.00% 60.00% Increase winter rape land by 10% Increase maize land by 10% Exclude cover crops 10% setaside of agricultural land 50% more org. fertilizer 50% less org. fertilizer 100% less org. fertilizer 50% more min. fertilizer 36.11% 50% less min. fertilizer 100% more min. fertilizer 8 Paper: Huang, Hesse, Krysanova, Hattermann, (in preparation)

9 Study on climate change impacts on water resources in Germany 8 0'0"E 10 0'0"E 12 0'0"E 14 0'0"E 16 0'0"E 54 0'0"N 54 0'0"N 6 0'0"E Ems Weser Rhein 52 0'0"N The investigation is integrated in the German study. 52 0'0"N Elbe 50 0'0"N 50 0'0"N 48 0'0"N Danube 48 0'0"N 6 0'0"E 8 0'0"E 10 0'0"E 12 0'0"E 14 0'0"E 16 0'0"E Figure 1: The five main river basins in Germany and selected gauges. 9 Objective: Analysis of vulnerability of water resources and waterrelated sectors to climate change in Germany. Study strategy: 9 Setup of the model SWIM for five main river basins in Germany (Ems, Weser, Elbe, Rhine and Danube) [ready] 9 Simulation of climate change impact on water resources applying a variety of regional climate scenarios, identification of robust trends and uncertainty quantification [ready] Study on climatic hazards and consequences for different sectors [to be done] Adaptation strategy to climate change in Germany [to be done]

10 Climatechangeimpacton waterdischarge Discharge in m 3 /s Problem for power production? Power plant Veltheim (a) 100 scenario included 50 scenario included Mean scenario Reference Discharge in m 3 /s Problem for tourism and ecology? Spreewald nature resort (b) 100 scenario included 50 scenario included Mean scenario Reference Average day Average day Problem for navigation? Cargo transport on the Main Problem for agriculture? Hofkirchen (Danube) 10 Discharge in m 3 /s (c) 100 scenario included 50 scenario included Mean scenario Reference Average day Gauges Germany River nets Runoff (mm/a) Kilometers < > 20 Discharge in m 3 /s (d) 100 scenario included 50 scenario included Mean scenario Reference Average day Map: differences in average annual runoff generation: ( ) minus ( ).Figs. ad: seasonal water discharge for 100 scenario realizations (grey) compared with that in the reference period red) for selected gauges.

11 What is needed to improve impact assessment? Reliable climate scenarios and land use change scenarios, e.g. RCM climate scenarios with ~10 km resolution to improve precipitation projections at the river basin scale; Intercomparison of climate scenarios (like PRUDENCE project) for different regions; Processbased hydrological models validated for historical period at the river basin scale; their uncertainty related to input data and parameters has to be investigated in advance; Intercomparison of hydrological models used for impact assessment 11