IMPRINTS Final Workshop Brussels September 27 2011 Marc

IMPRINTS Final Workshop Brussels, September 27, 2011 Marc Velasco – Researcher at CETaqua, Barcelona www. imprints-fp 7. eu Flash Floods in a changing context: Importance of the impacts induced by a changing environment

IMPRINTS Final Workshop, Brussels, September 27, 2012 Table of contents • Sub Project 5 • Review of current practices & past experiences • Future scenarios • Future risk assessment • Mitigation and adaptation • Conclusions

IMPRINTS Final Workshop, Brussels, September 27, 2012 Sub project 5 FF & DF risk management and mitigation in changing environments • Review of current practices & past experiences • Creation of global change scenarios ▫ Climate ▫ Land-use ▫ Forest fires • Development of a methodologies to assess the impacts future changes ▫ Risk mapping ▫ Rule-based system • Provide guidelines for practitioners to design mitigation and adaptation measures

IMPRINTS Final Workshop, Brussels, September 27, 2012 Review of current practices & past experiences Prevention Response Compilation of FF & DF follow-up · Coordinationstudies of organizations involved · Risk estimation · Land use regulations · Unit to monitor the post-crisis • Description of impacts · Follow-up studies · Integral analysis to plan protection infrastructures · Improve warnings transmission • Improvements on the local risk management · Infrastructure inventory (maintenance) · Promote hydrometeorological systems · Natural floodplains (water retention) Continuous maintenance • Compilation of lessons learnt ·classified by · Hydrometeorological forecasting systems · Historical FF and DF databases (learn from past) ▫ Prevention ▫ Preparedness ▫ Response Preparedness · Review▫and update emergency plans (real effectiveness) Dissemination and education · Future changes (i. e. climate and land use) · River bed maintenance · Evacuation maps · Training and plan evacuation simulations Dissemination and education · Exchange between experts · Diversify the mechanisms to disseminate · Risk culture: o sociological surveys o flood marks o hazard maps o… · Education programmes at schools

IMPRINTS Final Workshop, Brussels, September 27, 2012 Creation of global change scenarios • Future climate scenarios ▫ Extreme precipitation assessment • Future land-use scenarios ▫ Urban land-use ▫ Rural land-use • Future forest fires scenarios

IMPRINTS Final Workshop, Brussels, September 27, 2012 Future climate scenarios Llobregat basin • Data used Institution Downscaling method SMC Dynamical Model GCM RCM Output resolution ECHAM 5 MPIOM MM 5 15 km, 6 h Observations Altava-Ortiz 3 km, daily SRES scenarios Control period Future scenarios A 2, B 1 1971 - 2000 2001 - 2100 1971 - 2000 MPI-MET Dynamical ECHAM 5 -r 3 REMO 25 km, daily A 1 B 1961 - 2000 2001 - 2100 METO-HC Dynamical Had. CM 3 Q 0 Had. RM 3 Q 0 25 km, daily A 1 B 1961 - 2000 2001 - 2100 Observations Spain 02 20 km, daily • Models validation • Temporal future trends • Future spatial patterns 1950 - 2003

IMPRINTS Final Workshop, Brussels, September 27, 2012 Future climate scenarios Extreme precipitation assessment • Generalized Extreme Value functions • Future scenarios; periods of 30 years • High variability and uncertainty GEV fitted to the annual maxima daily precipitation for the control (1971 -2000) and future periods simulated with SMC for the A 2 scenario in the south Llobregat basin GEV fitted to the annual maxima daily precipitation for the observations (1971 -2000), the control (1971 -2000) (dashed) and the climate models results (1971 -2100) (solid) showing the minimum and maximum intensity in the Llobregat basin

IMPRINTS Final Workshop, Brussels, September 27, 2012 Future land-use scenarios Urban land-use • Corine database • JRC’s MOLAND model Urban land-use maps in the south Llobregat basin coming from Corine database (2000) and MOLAND A 2 future scenario (2040)

IMPRINTS Final Workshop, Brussels, September 27, 2012 Future land-use scenarios Rural land-use • Eururalis project data Llobregat 2000 Llobregat 2030 A 1 Llobregat 2030 A 2 Llobregat 2030 B 1 Llobregat 2030 B 2

IMPRINTS Final Workshop, Brussels, September 27, 2012 Forest fires scenarios Canadian Drought Code • Depends on T and P • Validation with actual forest fires • Daily calculation of CDC > 400 Annual CDC computed on the Llobregat basin during the historical period. The highest value occurred in 1994 when the most significant forest fire occurred. Historical and future scenarios of CDC on the Llobregat basin based on observations and SMC climate scenario A 2 for three time periods

IMPRINTS Final Workshop, Brussels, September 27, 2012 Future risk assessment Risk = Hazard x Exposure x Vulnerability Low Llobregat basin, showing the flood plains for a 500 year return period event. Llobregat basin I – T relationship for a 24 h duration for the A 2 SRES scenario, for the control period and the future scenario 2040. Weighing function to update the hazard values for the future rainfall scenarios.

IMPRINTS Final Workshop, Brussels, September 27, 2012 Future risk assessment Risk = Hazard x Exposure x Vulnerability map for the A 2 land use scenario for 2040. Urban land use in the Low Llobregat area: Urban land use from Corine 2000 (a); and A 2 urban land use scenario for 2040 (b).

IMPRINTS Final Workshop, Brussels, September 27, 2012 Future risk assessment • Overlaying the three variables and multiplying the weights Hazard 135 69 65 45 42 18 6 810 414 390 270 252 108 5 675 345 325 210 90 Vulnerability 4 3 540 405 276 207 260 195 180 135 168 126 72 54 2 270 138 130 90 84 36 Risk maps for the south Llobregat basin for the (a) current situation (2000), (b) future A 2 – A 2 scenario (2040) (c) and its difference 1 135 69 65 45 42 18

IMPRINTS Final Workshop, Brussels, September 27, 2012 Rule based system • Forecasting system that allows to link real-time observed values with expected hazard in probabilistic terms ▫ Simplification of a hydrological model with shorter lead times ▫ Operational use: issue warnings ▫ Considering high percentiles to represent extreme events • Governing variables for FF ▫ Antecedent soil moisture ▫ Forecasted rainfall

IMPRINTS Final Workshop, Brussels, September 27, 2012 Rule based system • Anoia basin ▫ Ocurrence �Moderate increase �Two exceptions ▫ Intensity �Generalized increase �Even for the exceptions Time series of the discharge values in the Anoia sub-basin. Period Control (1980 -2009) Scenario A 2 (2011 -2100) Scenario B 1 (2011 -2100) # POT per year (for each sub-period) 0. 86 20112040 20412070 20712100 0. 93 0. 53 0. 80 1. 07 0. 87 GP distribution fitted to the POT discharge values of the Anoia sub-basin for the control (1980 -2009) and future periods for the A 2 (left) and B 1 (right) scenarios.

IMPRINTS Final Workshop, Brussels, September 27, 2012 Mitigation and adaptation • Important changes may occur, but uncertainties are high and difficult to assess • Change of paradigm must be done: ▫ From «Fighting against Floods» to «Living with floods»

IMPRINTS Final Workshop, Brussels, September 27, 2012 Mitigation and adaptation • Implementation of EC Floods Directive and development of FRMP is crucial ▫ Promoting communication and creating a risk culture ▫ Implementing non-structural measures, which are robust and win-win �Early warning systems �SUDS �Local mitigation strategies (involving the population) �Etc.

IMPRINTS Final Workshop, Brussels, September 27, 2012 Conclusions • Climate projections strongly depend on models ▫ Need for further research ▫ Regionalized models are crucial • High variability and uncertainties ▫ Present everywhere ▫ Specially for extremes ▫ Use results with care • Mitigation and adaptation ▫ Implementation of EC Floods Directive is crucial ▫ Change of paradigm is needed ▫ Non-structural measures must be used

IMPRINTS Final Workshop, Brussels, September 27, 2012 Marc Velasco mvelasco@cetaqua. com Àngels Cabello acabello@cetaqua. com http: //imprints-fp 7. eu/