The rising concentrations of carbon dioxide and other greenhouse gases have caused observed physical, chemical and biological changes in the oceans, with further changes projected over coming decades. The impact of climate change on the oceans are profound, with rapid warming in ocean hotspots combined with extreme events such as marine heatwaves changing the distribution and abundance of a wide range of marine species. Further, ocean acidification, sea level rise, and deoxygenation may have important consequences for the marine ecosystems and the ecosystem services derived from the ocean. These observed and future ocean changes are irreversible on the timescale of many centuries. As a result, management of marine resources, for both extractive (for example, fishing) and non-extractive (for example, marine tourism) will need to account for the effects of climate change. For example, changes in abundance of marine species will impact harvesting levels and ecosystem structure, while changes in species’ distribution will challenge place-based management and agreements between nations. Adaptation to some of these changes will be possible; however, without substantial reduction in greenhouse gas emissions the oceans will change and not provide the same support for human activities as currently enjoyed. The changing nature of the ocean, and the impact it may have on ecosystems and communities, represents a huge challenge to future community interactions at local, national and international scales. It also raises the possibility of active intervention in the climate system to minimize the impacts of climate change which will introduce a complex set of issues to be considered before implementing any intervention.
Hobday A. J. & Matear R. J., 2020. The impact of climate change on oceans: physical, chemical and biological responses. In: McDonald J., McGee J. & Barnes R. (Eds.), Research Handbook on Climate Change, Oceans and Coasts, pp. 27–47. Edward Elgar Publishing. Chapter (restricted access).
