Marine Extremes: Are they changing and why? Seminar

Global mean sea level rise has long been argued as part of the evidence of climate change. Changes in wave height and storminess have also been detected in parts of the world. However the risks to coastal regions, offshore structures and ship do not arise through the slow change of the mean sea level or wave heights but through changes in the frequency the duration or the size of extremes. Detecting changes in extremes in mean sea level or wave heights and attributing them to changes in forcing parameters is complicated because these occur through the combination of more than one factors. Assessing the changes of extreme phenomena for the future is hampered further by limitations in the modeling of climate under scenarios of increased atmospheric concentrations of greenhouse gases. This seminar will describe work done in understanding changes in extreme sea levels and waves in various parts of the world and will argue the need for continuing observational and modeling work in marine extremes.