POTENTIAL CHANGES IN THE JOINT PROBABILISTIC DESCRIPTION OF THE NORTH ATLANTIC WAVE CLIMATE

摘要

Climate changes include natural climate variability and anthropogenic climate change. The latter is leading to global warming and causes changes in metocean conditions. For most marine structures waves represent the dominant environmental load. Therefore, projections of changes of wave characteristics in the 21st century are crucial with respect to design and marine operations. The study investigates potential changes in simultaneous occurrence of significant wave height and spectral wave period in twelve North Atlantic locations by comparing the past and future wave climate. Two IPCC emission scenarios, with radiative forcing of 4.5 and 8.5 W/m~2 by the end of the 21st century, have been selected to project future wave conditions. The third generation (3G) wave model WAM with a resolution of 50 km is used to simulate waves. The model has been forced with winds obtained from six CMIP5 climate models for the historical period 1971-2000 and the future period 2071-2100 for the two emissions scenarios. Wave climate projections obtained from one climate model and one ensemble member are presented herein to indicate potential changes in extreme wave characteristics derived from the long-term joint probabilistic model of significant wave height and spectral wave period. Deviations between the past and future wave climate are shown, given attention to the shape of the joint distribution and wave steepness. Uncertainties associated with the presented results are discussed.