The Global Coast: A View from the Open Ocean

Many global problems such as climate change, sea level rise, or ocean acidification influence in particular the ecosystems and communities along the coasts. Coastal regions on the other hand provide the ‘boundary conditions’ for the deep ocean. Traditionally, coastal research concentrated on local or regional approaches and problems. Methods and techniques developed there can, however, be relevant in a wider context. As part of our research focus area Global Coast we investigate the relevance of coastal waters for global processes, as for example carbon exchange processes with the open ocean or oceanic energy budgets. The two-pronged approach combining observations and models concentrates on the investigation of specific coastal “classes”, similar to those used by Laruelle et al. [2013] for coastal areas, i.e., typical structures that are potentially representative for larger stretches of coast lines or shallow seas and can be used as proxies for multiple coastal areas. Global ocean model output at the border between deep and shallow regions (shelf breaks) is analyzed in context with available data to determine characteristics for these “classes”, for example, shared mass and energy or carbon budget properties. The differences between models in this “ocean-to-coast” approach are analyzed and compared to traditional “coast-to-ocean” classifications based on analyses of coastal topography, analysis of watershed river basin properties and others. These efforts are geared towards developing a relatively simple system that allows us to approximate the contribution of coastal areas to global energy and carbon budgets as long as numerical models with globally sufficiently resolved coast lines are computationally still too expensive.