Conference Agenda

This thematic session aims at discussing relevant research topics in the context of the transition to carbon neutrality, in the context of the Ocean. The goal is to discuss possible research avenues that may contribute to a more environmentally friendly transition, by integrating ecosystem valuation and natural-capital accounting into economic decision-making, capitalizing on Portugal’ exceptional geographical location and the maritime area under Portugal’s sovereignty representing almost the terrestrial area of EU.

 

A) Global climate regulation service provided by deep-sea ecosystem services/the deep ocean/the ocean. 

The ocean offers humanity several vital ecosystem services, namely global climate regulation services. Coastal and marine ecosystems sequester and store CO2 - widely referred to as Blue Carbon - thus helping to reduce the concentrations of greenhouse gases in the atmosphere. It is estimated that, since 1850, the global ocean has sequestered c. ¼ of total anthropogenic emissions, and between 2014 and 2023 about c. 2.9 +- 0.4 GtC/year. This process relies on the ocean carbon pump, which has two key components: the biological pump, where marine organisms transfer carbon to the seabed through the food web, and the physical pump, which moves carbon-rich waters into the deep ocean, particularly in polar regions where cold temperatures enhance CO₂ absorption.

 

One pressing but still widely unanswered methodological question is how to value this service, especially in deep-sea environments. Some authors have used carbon market prices to assess its economic value. However, it is widely recognized that market values are a clear underestimation of the social cost of carbon (SCC). Besides, as SCC estimates are marginal values they should not be used to assess the value of the carbon stored at a given time T, but, instead, to estimate the value of one ton of carbon sequestered at T over its residence time.

 

Since the estimation of the carbon absorbed by the ocean encompasses important challenges, the goal of this session is to contribute to this discussion, advancing research in the field.

 

B) Natural Capital Accounting

The Natural Capital Accounting (NCA) develops a framework that systematically measures and reports on natural capital stocks and flows. For sustainability purposes, there is a need to develop national natural-capital accounts that capture both land and marine ecosystems. Portugal’s forthcoming Ocean Natural Capital Accounting (2026) as set by the Portuguese Government illustrates how national initiatives can pioneer valuation and policy design, an essential step to ensure a more equitable and sustainable transition. Importantly, with careful natural capital accounting, it is possible to better understand the “true” value of the environmental impacts of development, which in turn impact on decarbonization, deforestation, and migration patterns. Accounting for the condition of natural ecosystems and assessing their economic value in a systematic way is key to transform Portugal’s Ocean Economy into a Blue Bioeconomy.

 

C) Blue Economy

Coastal and marine ecosystems, such as seagrass meadows, salt marshes, and mangroves, are particularly effective at sequestering carbon, often referred to as “blue carbon”. Protecting these habitats is key to fight against global warming, as they not only capture carbon but also support marine biodiversity and provide vital ecosystem services. Portugal’s Atlantic geography offers a frontier for offshore renewables, green shipping, aquaculture, and coastal resilience. The blue economy can link energy, logistics, finance, and environmental stewardship. The large coastal area hosts many of those activities which could contribute to a more sustainable transition in those fields also improving the livelihood of local populations. However, this requires a consistent, updatable, regulatory framework with strict monitoring and enforceable rules, that identifies both the possible areas where economic activity can take place (e.g., fisheries, aquaculture, touristic activities, surfing, ports, wind offshore installations), and under what conditions, and those that should be preserved (e.g., coastal Natural Parks and Marine Protected Areas), avoiding possible conflicts. This is the role of Marine Spatial Planning. Under these conditions, and for public policy purposes, it will be interesting to study the possible development of a voluntary Blue Carbon Credit market that either (i) avoid or reduce GHGs emissions, or (ii) remove or sequester those emissions, while ensuring additionality, for cost-effectiveness (or efficiency) purposes. Further offshore, on the continental shelf, carbon stocks are also not well quantified or understood. Despite recent controversy over whether human activities such as trawling can impact carbon stocks and contribute to carbon emissions, there is little empirical scientific research on the impacts of trawling on carbon dynamics, and sedimentary carbon stocks. Also, the quantitative contribution of marine animals (such as whales and fish) to Blue Carbon is also uncertain. Moreover, continental shelf systems are under increasing anthropogenic impacts, from fisheries and dredging activities, to installation and decommissioning of energy structures, such as wind turbines. Yet, the impact on carbon stocks and sequestration is largely unknown. This makes it challenging to value the carbon, particularly for environmental economic and carbon credit accounting. As in coastal Blue Carbon ecosystems, some of the carbon sequestered may originate from land, not classifying as Blue Carbon.