In recognition of Oceans Day at the Twenty-first Conference of the Parties to the United Nations Framework Convention on Climate Change (COP 21), the International Council for the Exploration of the Sea (ICES), the North Pacific Marine Science Organization (PICES), and the Intergovernmental Oceanographic Commission of UNESCO (IOC-UNESCO) present highlights from their Third International Symposium on "Effects of climate change on the World's Oceans", held in Santos, Brazil, earlier this year.
Discussing the effects of climate change on the world's oceans is critical to understanding how these changes will impact society. We need to understand what is changing, how it is changing, how fast it is changing, and what options are available to reduce impacts.
The Third International Symposium on "Effects of climate change on the World's Oceans" provided opportunities for the international science community to discuss the latest information, understanding, and assessment of the impacts of climate change on our oceans.
Linkages between natural science and the human dimension of climate change impacts were provided, with a focus on coastal communities, management objectives, and governance adaptation.
Scientists highlighted advancements in modelling and understanding climate change impacts on biological and physical processes. Ocean models continue to improve in process understanding and resolution. Global high-resolution models can now describe scenarios of climate change effects, some of which are already being applied to net primary and zooplankton production models. However more focus needs to be directed towards developing dynamic, region-specific high-resolution, downscaled ocean models, where a gap remains.
Influential work was presented on acclimation and genetic adaptation to ocean acidification, deoxygenation, and temperature and salinity changes. The potential dangers of these impacts are obvious as any adaptation has costs, indicating a more complex picture than previously understood.
As our understanding of processes improves, so does our understanding of species' distributional changes in response to climate change. We are better at resolving species' responses and migrations that will not always be homogenous or consistent as habitat preferences, tolerances, and other ecosystem interactions also determine responses.
The symposium benefitted from the significant input of social scientists who are integrating physical and biological research results with human uses and reliance on marine ecosystems to identify potential management options. The most effective policies will be those that are flexible and allow adaptive responses to climate change.
Climate change will have a disproportionate impact on coastal societies in the developing world. In some places, such as Bangladesh and Australia, tools are made available for societies to quantify their level of risk and tailor responses. An area for future research in climate change impacts on the oceans will be the inclusion of human impacts such as changes in land use and population growth.
Science has clearly demonstrated that effects related to climate change are evident in our oceans and that these effects will have impacts at various ecological and societal levels. ICES and PICES will continue to coordinate efforts in the northern hemisphere, along with the IOC on the international level, to understand, estimate, and predict these impacts.