Ocean Acidification

Our oceans are changing fast, and, in particular, human-induced climate change has negative effects on the ocean. Ocean acidification (OA), sea-level rise, and ocean warming are endangering oceanic ecosystems and ecosystem services simultaneously. In addition, other human activities cause ocean stress at the same time, such as fishing or pollution. The research and understanding of these repercussions of climate change are growing, but not everything is understood. In particular, the interaction between different repercussions of climate change and other ocean stressors still requires research. Nevertheless, science is progressing fast; for example, nature-based solutions could be a helpful tool in the fight against these negative influences on the ocean. As science advances, law and policy must also evolve to prevent changes in the ocean environment and avoid reaching critical tipping points. These tipping points mark significant and often irreversible shifts in the climate system, including the ocean.

The International Tribunal for the Law of the Sea (ITLOS) has issued its highly anticipated Advisory Opinion on Climate Change and International Law, following a request from the Commission of Small Island States on Climate Change and International Law (COSIS). The landmark Advisory Opinion elucidated numerous contentious issues around the interplay between the climate change and the law of the sea regimes. This article critically examines the ITLOS Advisory Opinion with respect to the relationship between the Paris Agreement and the United Nations Convention on the Law of the Sea (UNCLOS), contextualising them within the extensive academic and political discourse preceding the Opinion. In particular, the lex specialis question is brought into sharper focus. The Tribunal rejected the notion that the Paris Agreement is lex specialis with respect to climate change impacts on the ocean and clarified the nexus between adaptation measures and the overarching obligation to protect and preserve the marine environment. The analysis reveals that the Advisory Opinion conveys a generally critical view of the Paris Agreement, and may, despite its imposition of far-reaching obligations upon States to mitigate marine pollution from greenhouse gases, inadvertently undermine global efforts to combat climate change. However, by articulating concrete legal obligations for States under the UNCLOS to prevent, control and reduce marine pollution from greenhouse gas emissions, the Advisory Opinion could further strengthen the legal foundations for domestic and international climate change litigation and elevate the profile of the oceans in global climate change negotiations

Ocean acidification (OA), an alteration of seawater chemistry caused primarily by anthropogenic carbon emissions, is a global issue. However, the local expression of OA can vary widely in nearshore waters around the world. This is due to localized factors such as river input, eutrophication, topography, location (e.g., temperature), and sensitivity of local species. Human impacts from OA also vary depending on societal uses of the ocean and its resources. Managers, policy­makers, and governments need to understand the status and susceptibility of their regions in order to make effective decisions and drive policy. In the early 2000s, scientists recognized the need for a global ocean acidification observing system and called for a coordinated approach to effectively assess global as well as local status with consistent methods. As a result, the Global Ocean Acidification Observing Network (GOA-ON) was formed in 2012 with three goals: (1) to improve understanding of global OA conditions, (2) to improve understanding of ecosystem responses to OA, and (3) to acquire and exchange data and knowledge necessary to optimize modeling of OA and its impacts (Newton et al., 2015; Tilbrook et al., 2019).

On May 21, 2024, the International Tribunal for the Law of the Sea (the Tribunal) delivered a unanimous advisory opinion on the Request submitted to the Tribunal by the Commission of Small Island States on Climate Change and International Law. This was the first advisory opinion on climate change obligations issued by an international judicial body, and the first of three anticipated advisory opinions on climate change obligations from international judicial bodies. The request had been submitted on December 12, 2022 by the Commission of Small Island States on Climate Change and International Law (COSIS). Two questions on obligations of states parties under the United Nations Convention on the Law of the Sea (UNCLOS) were posed in the request: (1) what are the specific obligations to prevent, reduce, and control pollution of the marine environment in relation to the deleterious effects that result, or are likely to result, from climate change and ocean acidification, which are caused by anthropogenic greenhouse gas (GHG) emissions into the atmosphere; and (2) what are the specific obligations to protect and preserve the marine environment in relation to climate change impacts and ocean acidification. A total of 34 states parties to UNCLOS and nine intergovernmental organizations submitted statements, and 33 states parties and four intergovernmental organizations made statements during the oral proceedings.

Marine Scientific Research (MSR) under Sustainable Development Goal—14 (SDG 14) has envisioned a new dimension of cooperation for marine environmental protection. This chapter has taken the approach of MSR as provided in SDG 14 to provide a cooperative approach for MSR to protect the marine environment. This chapter analyzes the international law provisions dealing with MSR envisioning cooperation for the protection of the marine environment. The chapter has taken three perspectives of the marine environment: (i) climate change, (ii) fisheries preservation, and (iii) marine protected areas, along with scientific approaches required for marine pollution prevention. The conclusion of this chapter follows the challenges and opportunities for MSR cooperation, which could be a future course of research on the subject matter.

The 17 SDGs adopted by the UN as part of the 2030 Agenda constitute a global framework for achieving sustainable development. They have become a strategic priority and focus of action for countries worldwide. However, almost halfway into the 2030 Agenda process, its implementation has been seriously hindered by climate change and the COVID-19 pandemic, with global progress in individual goals even facing setbacks.

The 17 SDGs adopted by the UN as part of the 2030 Agenda constitute a global framework for achieving sustainable development. They have become a strategic priority and focus of action for countries worldwide. However, almost halfway into the 2030 Agenda process, its implementation has been seriously hindered by climate change and the COVID-19 pandemic, with global progress in individual goals even facing setbacks. The goals will not be achieved by 2030 unless implementation is accelerated. In 2021, about one-tenth of the world’s population went hungry; more than three billion people were at health risk due to scarce data on the water quality of rivers, lakes, and groundwater; globally, 733 million people still lacked access to electricity; cities were hard hit by the COVID-19 pandemic; four key climate change indicators—global greenhouse gas concentration, sea-level rise, ocean heat, and ocean acidification—hit record highs; increasing ocean acidification, eutrophication, and plastic pollution put the livelihoods of billions of people at risk; and continued global deforestation, land and ecosystem degradation, and loss of biodiversity posed major threats to human survival and sustainable development (UN 2022; Sachs et al. 2022).

Science, technology, and innovation can help address these major challenges, primarily to support assessments at national and local scales and inform policy-making by enhancing data capacity for SDG monitoring and evaluation. The UN Sustainable Development Goals Report 2022 pointed out that the pandemic has delayed the development of new national statistical plans worldwide, and there are still considerable gaps in the geographical coverage and timeliness of global data on indicators (UN 2022). Meanwhile, the current indicator data are primarily of coarse-grained statistical values, with the time resolution mostly being “annual” and the spatial resolution mostly “national,” incapable of disaggregation by geographical locations, population distributions, and environmental differences, which are crucial to thoroughly assessing regional differences in SDG progress and identifying those lagging behind. Thus, there is not enough data to effectively inform sub-national governments’ decision-making. According to estimates from the Organisation for Economic Co-operation and Development (OECD), 105 out of the 169 SDG targets will be challenging to achieve without sufficiently engaging sub-national governments (OECD 2020). Many are environmental targets sensitive to spatial and temporal changes.

As the core of digital technology, big data has become an important engine of digital transformation across societies. Big Earth Data, a key part of big data, mainly composed of Earth observation and geospatial data, has the advantages of easy acquisition, timely updates, objective results, and higher resolution. Moreover, it covers different spatial scales and geographical locations free from administrative fragmentation, allowing a more accurate assessment of SDG indicator progress and prompt detection of problems. Its role in analyzing the complex interactions and co-evolution between nature and social systems will contribute to the overall understanding and realization of the SDGs.