MEL Seminar | Assessment, future projection, and countermeasures for the impacts of ocean warming, acidification, and deoxygenation on coastal ecosystems and society

Bio：

Masahiko Fujii is Professor of International Coastal Research Center, Atmosphere and Ocean Research Institute, the University of Tokyo, Japan. He has been involved in research and education on assessment, future projection, and mitigation and adaptation measures for the impacts of ocean warming, acidification, and deoxygenation on coastal ecosystems and society. Recently, he has also been studying the impacts of ocean acidification on coastal ecosystems and marine biodiversity by examining in detail the marine environment around shallow-water CO₂ seeps as natural analogues of the future ocean.

Abstract：

Ocean warming and acidification mainly caused by increased anthropogenic CO₂ emissions have become apparent both globally and in the seas around Japan. In addition, the rise in water temperature associated with ocean warming has also led to deoxygenation, which, combined with the impacts of local human activities in coastal areas, has led to an era of significant changes in the marine environment. These changes have the potential to alter the structure and function of coastal ecosystems through their impacts on marine organisms and subsequently the local industries such as fisheries and marine tourism. In addition to these long-term phenomena, concerns have been raised that coastal ecosystems in Japanese waters are facing severe impacts caused by relatively short-term localized events. For example, the major fisheries target species in northern Japan have changed significantly over the past decade, and this is partly considered to be largely influenced by extremely high water temperatures brought about by the Kuroshio Large Meander. Furthermore, as climate change progresses, the increasing frequency and intensity of heavy rainfall are anticipated to exacerbate the impacts of coastal acidification on aquaculture shellfish species. To minimize the combined impacts of these diverse phenomena, occurring at different spatio-temporal scales, on coastal ecosystems and society, it is necessary to understand the current situation, project the future, and implement region-specific countermeasures. This presentation will introduce the impacts each phenomenon is having, either individually or in combination, along with examples of past efforts concerning their projection and countermeasures.