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Increased ocean observations urgently needed, according to UN State of the Ocean Report 2024   

3 June 2024

PML’s Professor Steve Widdicombe was among the authors 

IOC UNESCO’s 2024 State of the Ocean Report was published today (3rd June 2024), offering an overview of the current state of the global ocean, to mobilize global society to act – and monitor progress – towards global goals. More than 100 authors from 28 countries contributed to the Report, including PML’s Director of Science Professor Steve Widdicombe, who shared expertise on the status and trends of ocean acidification. PML’s Professor Helen Findlay also acted as a reviewer.  
Access the 2024 State of the Ocean Report >> 

In the introduction to the report, Vidar Helgesen, Executive Secretary of the Intergovernmental Oceanographic Commission of UNESCO says:  

“The message remains that observations and research is falling short and hence there is a lack of adequate and aggregated data. But as more states, industries and organizations realize that we need to measure in order to manage and protect marine ecosystems, we gradually get more data, get deeper into the issues, and can include new topics of research. 

Every indication is, however, that the ocean crisis is developing faster than our knowledge of it. We therefore need to accelerate the mobilization which is under way in the UN Decade for Ocean Science for Sustainable Development 2021-2030. We need to transform ocean science and our relationship to it. 

We need better knowledge as a basis for sustainable ocean planning and management, within and beyond areas of national jurisdiction. And we need a much stronger, much faster and more dynamic interplay between ocean knowledge, policy and action.” 

Professor Widdicombe stresses the importance of long-term data monitoring in relation to ocean acidification, as detailed in the Report: 

“Ocean acidification is a global issue - a phenomenon happening across all of the world’s oceans - and this report has shown a mean global increase in ocean acidification in all ocean basins and seas. But observations of the rate of ocean acidification, in its pattern and scale, show great regional variability. This is especially the case with observations made in the open ocean compared to those made in coastal areas.

Observations of ocean acidification in the open ocean have shown a consistent and continuous decline in pH, with an average global surface ocean pH decline of 0.017–0.027 pH units per decade since the late 1980s. Whereas coastal areas present a more varied picture, which a result of a multitude of factors, including the fact that coastal areas absorb more carbon dioxide than the open ocean, and that these coastal areas are subject to a wide range of additional processes – both natural and anthropogenic - that affect the carbonate chemistry of the water. Coastal zones are significantly more complex in terms of physicochemical conditions than the open ocean, due to the interaction of multiple drivers; such as freshwater from rivers, wastewaters, mixing, upwelling, biological processes, and sediment interactions.

 It’s because of these stressors and processes that the overall pH is declining at faster rates in the shallow coastal regions than in the open ocean, and this is worrying, as most of the ocean’s biodiversity is found in the coastal zones, in addition to coastal regions being where we humans interact most with the ocean. As a result of this natural variability, we urgently need longer term data sets for coastal areas in order to determine the time of emergence of ocean acidification trends.” 

Professor Steve Widdicombe has been instrumental in developing the understanding of the effects of ocean acidification on the marine environment, since the term was first coined in 2003. He is Co-Chair of the Global Ocean Acidification Observing Network (GOA-ON) - a collaborative international network with around 1,000 scientists from more than 100 countries, to detect and understand the drivers and impacts of ocean acidification. He also co-leads the UN Ocean Decade endorsed programme ‘Ocean Acidification Research for Sustainability’ (OARS), which aims to provide society with the observational and scientific evidence needed to sustainably identify, monitor, mitigate and adapt to ocean acidification; from local to global scales. 

He added:  

“Despite an increasing number of ocean acidification observations, the current coverage is inadequate, with time series not long enough to determine trends and data gaps due to lack of observations found in all areas.” 

Access the 2024 State of the Ocean Report >> 

Related information

About the State of the Ocean Report: During the 2022 United Nations Ocean Conference, taking place from 27 June to 1 July, the United Nations Educational, Scientific and Cultural Organization (UNESCO) launched the “State of the Ocean Report”, offering a brief, accessible, one-stop overview of the current state of the ocean, and to mobilize global society to act - and monitor progress - towards global goals. 

The State of the Ocean Report has the ambition to inform policymakers about the state of the ocean and to stimulate research and policy actions towards ‘the ocean we need for the future we want’, contributing to the 2030 Agenda and in particular SDG 14, as well as other global processes such as the UNFCCC, the Convention on Biological Diversity and the Sendai Framework for Disaster Risk Reduction. 

Structured around the seven UN Decade of Ocean Science for Sustainable Development Outcomes, the Report provides important information about the achievement of the UN Ocean Decade objectives and, in the longer term, about ocean well-being. 

The different sections provide insights on ocean-related scientific activities and analyses describing the current and future state of the ocean, addressing physical, chemical, ecological, socio-economic and governance aspects. 


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