Climate change is transforming the world's oceans, with profound implications for ecosystems, fisheries, and coastal communities. The latest issue of ICES Journal of Marine Science presents research from the Fifth International Conference on the Effects of Climate Change on the World's Ocean (ECCWO5), held in Bergen, Norway, in April 2023. This collection of articles explores how climate-driven shifts in marine environments are affecting biodiversity, fisheries management, and ocean-based economies—and what actions are needed to mitigate and adapt to these changes.
Climate change and ocean science: a growing urgency
Since its launch in 2008, the ECCWO symposium series has been a critical forum for advancing global understanding of climate change impacts on marine ecosystems. Co-organized by ICES, PICES, the Intergovernmental Oceanographic Commission (IOC-UNESCO), and the Food and Agriculture Organization (FAO), ECCWO5 brought together 700 scientists and policymakers—both in-person and online—to share the latest research on ocean climate effects.
According to Geir Huse, lead author of the introductory article and symposium co-convener, the symposium underscored the urgency of integrating climate science into fisheries management, conservation, and policy frameworks. The impacts of marine heatwaves, ocean deoxygenation, and habitat loss are becoming increasingly severe, with cascading effects on ecosystems and human societies.
Key themes from ECCWO5
Ecosystem shifts and tipping points
One of the most pressing findings discussed at ECCWO5 is the dramatic impact of climate change on habitat-building species, such as coral reefs, seagrasses, and kelp forests. These species form the foundation of marine ecosystems, and their decline threatens biodiversity and fisheries. The symposium highlighted the need for continuous monitoring and predictive modeling to anticipate ecosystem shifts before irreversible tipping points are reached.
The role of fisheries in climate adaptation
Fisheries are both vulnerable to climate change and a potential part of the solution. ECCWO5 emphasized the importance of adaptive management strategies that incorporate climate projections into fisheries stock assessments. Research presented at the symposium called for a shift towards low-emission fishing, alongside improvements in sustainability measures and resilience planning.
Addressing ocean deoxygenation and acidification
Oxygen loss and increasing ocean acidity are emerging as critical challenges for marine life, yet they remain understudied. Symposium participants highlighted the need for more targeted research on how deoxygenation and acidification impact fish stocks, ecosystem productivity, and food security.
Integrating social and ecological approaches
Beyond the ecological changes, ECCWO5 placed strong emphasis on the human dimension of climate change. The conference stressed the importance of engaging stakeholders—including fisheries communities, policymakers, and Indigenous groups—to co-design climate adaptation strategies. Social-ecological research is key to ensuring that climate science translates into meaningful action.
Looking ahead: Bridging science and policy
As ocean climate change accelerates, ECCWO5 reaffirmed the need for stronger links between scientific research, policy implementation, and industry practices. The conference promoted the expansion of climate impact assessments, the adoption of ecosystem-based management approaches, and the prioritization of Findable, Accessible, Interoperable, and Reusable (FAIR) data-sharing principles.
The full symposium issue in ICES Journal of Marine Science presents a collection of studies that address these themes, offering insights into the evolving state of ocean climate science.
Read all submitted articles in ICES Journal of Marine Science's latest symposium issue, Effects of climate change on the world's oceans.
