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Abstract A substantial body of research now exists demonstrating sensitivities of marine organisms to ocean acidification (OA) in laboratory settings. However, corresponding in situ observations of marine species or ecosystem changes that can be unequivocally attributed to anthropogenic OA are limited. Challenges remain in detecting and attributing OA effects in nature, in part because multiple environmental changes are co-occurring with OA, all of which have the potential to influence marine ecosystem responses. Furthermore, the change in ocean pH since the industrial revolution is small relative to the natural variability within many systems, making it difficult to detect, and in some cases, has yet to cross physiological thresholds. The small number of studies that clearly document OA impacts in nature cannot be interpreted as a lack of larger-scale attributable impacts at the present time or in the future but highlights the need for innovative research approaches and analyses. We summarize the general findings in four relatively well-studied marine groups (seagrasses, pteropods, oysters, and coral reefs) and integrate overarching themes to highlight the challenges involved in detecting and attributing the effects of OA in natural environments. We then discuss four potential strategies to better evaluate and attribute OA impacts on species and ecosystems. First, we highlight the need for work quantifying the anthropogenic input of CO2 in coastal and open-ocean waters to understand how this increase in CO2 interacts with other physical and chemical factors to drive organismal conditions. Second, understanding OA-induced changes in population-level demography, potentially increased sensitivities in certain life stages, and how these effects scale to ecosystem-level processes (e.g. community metabolism) will improve our ability to attribute impacts to OA among co-varying parameters. Third, there is a great need to understand the potential modulation of OA impacts through the interplay of ecology and evolution (eco–evo dynamics). Lastly, further research efforts designed to detect, quantify, and project the effects of OA on marine organisms and ecosystems utilizing a comparative approach with long-term data sets will also provide critical information for informing the management of marine ecosystems.
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This content will become publicly available on January 1, 2026
The IAEA Ocean Acidification International Coordination Centre Capacity Building Program: Empowering Member States to Address and Minimize the Impacts of Ocean Acidification
Ocean acidification (OA) is broadly recognized as a major problem for marine ecosystems worldwide, with follow-on effects to the economies of ocean-dependent communities. The urgent need to mitigate and minimize the impacts of OA is a scientific and political priority, as highlighted by the latest Intergovernmental Panel on Climate Change report (IPCC, 2022) and by the inclusion of OA as a target in the United Nations Sustainable Development Goals (SDG). In addition, over 20 years of strong scientific evidence on the impacts of OA provides compelling arguments for urgent CO2 mitigation. Reducing CO2 emissions will require ambitious regulatory and economic instruments, as well as effective systemic changes across governments and societies. It is critical to implement adaptation measures to minimize the impact of OA, among other key environmental stressors, as the mitigation process takes time, and the impacts of OA are already felt globally. Assessing the impacts of solutions and their potential implementations requires information at local scales, considering the variabilities in marine ecosystem responses to OA (e.g., local adaptation, species redundancies).
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- Award ID(s):
- 2318309
- PAR ID:
- 10599839
- Publisher / Repository:
- The Oceanography Society
- Date Published:
- Journal Name:
- Oceanography
- Volume:
- 38
- Issue:
- 1
- ISSN:
- 1042-8275
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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