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Engineering Adaptation Strategies and Infrastructure Design Requirements to Deal with Climate Uncertainty – U ncertainty, Certainty (and the C ase of Coastal D efense). Hans von Storch Institute of Coastal Research Helmholtz Ze ntrum Geesthacht und Klimacampus Hamburg.
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Engineering Adaptation Strategies and Infrastructure Design Requirements to Deal with Climate Uncertainty –Uncertainty, Certainty (and the Case of Coastal Defense) Hans von Storch Institute of Coastal Research Helmholtz Zentrum Geesthacht und Klimacampus Hamburg 6th International Conference on Water Resources and Environment Research (ICWRER)Koblenz, Germany, June 3–7 2013.
Climate – Knowledge Uncertainty • Detectability of change • Characteristics of change: intensity, speed, signal-to-noise ratio (conditional upon time) • Attributability of change (various drivers) • Intensity and effectivity of claimsmaking by economic stakeholders and green ideology (post-normal science) • Presence and emergence of other drivers
Certainties • Risks exist and may change, some will. • Climate (statistics of weather) is changing – as well as associated probabilities of hazardous situations – due to elevated GHG levels. • A new “stationary” state will hardly be reached; statistics are getting instationary. • The level of adaptation to change depends on the success of limiting the change (Klimaschutz) • Scientific skeptic is needed. • Overselling of claims-making is counterproductive on the long run.
Certainties- the time dimension • Learning in time – in 10 years we know more than today, in 20 years more than in 10 years. • Societal values change in time • Technology changes – new, cheaper and more flexible answers to challenges will be available. • Drivers of change will become more – some gradually, some abrupt and surprising. • Success of limiting anthropogenic climate change gradually becomes a “known”
Consequences for today • Maintenance and regular modernization should consider perspective of future change and flexibility in responding to such change. • Decision needed as to when new adaptation measures should be implemented. • Consideration of change of all drivers. • Societal debate needed about options and timing. • Check of societal claims-making reflecting special interests.
Research Needs • Development of new or improved technology options for dealing with present and changing risk. • Monitoring of environmental state, which allows detecting changing risks and attributing to causes.
Coastal Defense: Detection, Attribution Differenceofmaximumheights in Hamburg and Cuxhaven 37 yeartrencs (2 x nodaltide) of regional sealevel in the German Bight black, green: tworeconstructionmethods rot – Cuxhaven, Albrecht et al. 2011 Storm surges in Hamburg elevatedbecauseofmodifyingtheriver Elbe – bothcoastaldefenseandshippingchanneldeepening
Green ideology misleading the public Claimed flooding associated with a sea level rise of 1 (?) m. Area protected by contemporary coastal defense against “normal” high tide sea level.
Coastal Defense Analysis for Coastal Defense in Schleswig Holstein (Landtag, Kiel), in 2009 Fortification of dikes in Schleswig-Holstein
Technology: Dykeovertoppingtolerance Currentlyovertoppingtolerances: • 3% of all – LowerSaxony • 2 l/(m∙s) – Masterplan Schleswig-Holstein • 0,1-1,0 l/(m∙s) – The Netherlands Resultsofovertoppingtest in Delfzijl/NL • Nodamageupto50 l / (m ∙ s) • Noseveredamageat 50 l (m ∙ s) • after artificialdamage still functioning Niemeyer & Kaiser 2008, NLWKN
Overall conclusion: Time! • When adapting to and talking about climate change three major, often overseen issues are • The issue is not new risk, but changing risk • Time is a key dimension – change occurs in time; development is instationary. • Knowledge, drivers and options for adaptation change in time.