During the two last days (Sept. 19.-20.), lectures were given by the internationally renowned fluvial delta specialists Prof. Yoshiki Saito and Prof. James Syvitski. Prof. Saito presented a detailed overview of delta definitions to us, illustrated by numerous classification diagrams bases on different parameters such as waves, tides, sediment inputs and grain size. Widespread literature references were called during the lecture which was especially convenient for those who would like to further deepen the topic in their own research. Saito then went on exemplifying this theoretical part by presenting the great deltas of the Asian region, e.g. the Ganges-Bramaputra-, Mekong- and Red River-deltas. He illustrated their development under the influence of sea-level rise, waves, tides, sediment inputs and human interventions.

Prof. Syvitski’s interesting talk on deltas complemented Yoshiki Saitos lecture very well as he presented numerous data bases providing raw data on e.g. topography or discharge and numerical models. He also encouraged us to question the quality of datasets, e.g.: the importance of data resolution in relation to the scientific question to be answered. Another very interesting aspect of Syvitski’s talk was his focus on scientific questions not yet answered, e.g. deltas are regarded as fluvial diverging systems while numerical models are able to represent converging systems. So there are difficulties to apply the scheme of present models to deltaic environments. That is why programming improvements are necessary to adapt these models to such environments, Syvitski pointed out.

Overall, the Ocean Hazards Summer School to me was a success, really interesting and rewarding for the participants, dealing with a wide variety of topics from local to regional coastal systems and different approaches covering a whole spectrum from technical to theoretical perspectives. So my bottom-line for this last week: It confirmed my interest for coastal environments and reinforced my motivation to study them.