Extreme waves and climate change: Accounting for uncertainties in design of marine structures

The underlying idea of ExWaCli is to enable stakeholders within the marine related industries to adapt to climate change by improving risk management of their activities. The project will contribute to increased safety at sea by expanding the knowledge o f how climate change may impact the design and operations within shipping, the offshore industry, aquaculture, harbours and other coastal activities. In ExWaCli known and well proven climate and wave models will be evaluated, modified if necessary and app lied to several combinations of models and emission scenarios to obtain a range of possible future wave conditions. The results will be used to estimate future design wave conditions and the associated uncertainties. Available approaches and software for carrying out structural reliability calculations is available within the industry since the mid-eighties. Also, complicated non-linear effects can be included by embedding a time domain simulation code in a reliability code, like the probabilistic analys is code PROBAN® (Det Norske Veritas, 2002). In ExWaCli these methods will be used , together with methods for Extreme Value Analysis on non-stationary processes. The latter will be further developed. Sensitivity studies will be carried out by SRA to iden tify the importance of the uncertainties to the failure probability of ship and offshore structures. We will also investigate the effects of the uncertainties in future wave conditions on loads and responses. The results will be included in recommendation s for revisions of Recommended Practices and rules of Classification Societies.