Unlocking the secret powers of the ocean floor

What impact does the ocean have on climate change? And how can it help mitigate the effects of global warming? The five-year Convex Seascape Survey is currently trying to find answers to these crucial questions by taking a closer look at the continental shelf seas’ ability to absorb carbon and fight climate change.

An interview with Gail Fordham
Photographs by Matt Jarvis, Henley Spiers, Michiel Vos and Shannon Moran

The global research project, developed in partnership by the Blue Marine Foundation, University of Exeter, and Convex Group Ltd, is now two years into its five-year lifespan. As part of the project, around 100 experts are “investigating, modelling and quantifying carbon storage in vast coastal seas around the globe whose carbon capacity is currently unknown”, according to the Blue Marine Foundation in the hope of generating important open-source data on how to manage the ocean sustainably and maximise its carbon-storage capabilities. Ultimately, they’re trying to determine how the seabed acts as a carbon sink, and how it could be an ally in slowing down climate change. Alongside generating scientific data, the project seeks to engage young people, the public, and decision-makers.

We spoke to Gail Fordham, grant manager at the Convex Seascape Survey, to find out more about the ambitious project.


Oceanographic (OM): In what phase is the Convex Seascape Survey currently? 

Gail Fordham (GF): “We are almost at the halfway point in our ambitious five-year, global research programme investigating how the ocean and climate are connected. Momentum has been building across the programme, and we now number up to 100 experts working from 19 institutions across nine different countries. We’re at an exciting juncture, with imminent fieldwork campaigns overseas, as well as results on the horizon with the recent submission of the first wave of research papers produced under the project.”

OM: How is the Blue Marine Foundation involved? What is your task within the survey?

GF: “Blue Marine Foundation is very proud to have brokered this project – one we believe to be the largest seabed carbon survey of its type in the world, thanks to our founder, George Duffield approaching Convex Group and the University of Exeter. This multimillion-dollar, cross-sector partnership embodies the collaborative approach and scale needed to answer one of the most important questions of our time: How can healthy oceans help combat climate change? Blue Marine manages the project and ensures it is effectively delivered. Professor Callum Roberts at the University of Exeter is leading the science consortium and Stephen Catlin of Convex Group has a fantastic pedigree in supporting climate projects of global significance.

Blue Marine is dedicated to restoring the ocean to health by addressing overfishing. We are well-connected in the blue carbon sphere, but continually finding that not enough data exists about the sequestration capabilities of the continental shelves and the effects of bottom-towed fishing, on seabed carbon stores. We leverage our expertise in marine conservation and our vast network within the environmental sphere to further this cause. Blue Marine’s role will be to ensure that this data is used to make informed decisions on sustainable ocean use for future generations.

As grant manager, I oversee the project’s development, delivery, and partner relations, ensuring all our activities meet the milestones we have set out. My role includes organising and attending Steering Committee meetings, managing finances, and representing the project at international conferences. I also support communications efforts and contribute to the education programme.”

OM: What is the main aim of the Survey? What are you trying to achieve and why is it important?

GF: “The Survey aims to provide robust, open-source data on the carbon sequestration capacity of shallow shelf seas around the world. We are investigating: Where, why and how does carbon become buried in the seafloor? Where does it come from? What role does life and biodiversity play? And what are the impacts of human disturbance vs. protection? Generating a new understanding of the ocean-climate nexus, we are specifically focussing on the little-studied carbon stored in ocean sediments. We will take this knowledge and put it into global carbon budgets to assess, properly for the first time, the significance of these stores.”

OM: How can the ocean help combat climate change?

GF: “The ocean can help combat climate change by absorbing and storing carbon dioxide from the atmosphere. It has been widely suggested that ocean ecosystems can help remove up to three of the five billion extra tonnes of carbon dioxide needed to be removed from the atmosphere each year if we are to stay within the 2-degree warming limit of the Paris Agreement. This is considerably less risky than geoengineering solutions, and surely an area worth exploring.

Vegetated marine habitats, such as mangroves, seagrass and saltmarsh are widely recognised blue carbon ecosystems which sequester carbon at rates much higher than terrestrial forests. However, their ability to mitigate climate change is ultimately limited by their small geographic extent, less than 0.2 percent of the global ocean. Continental shelf sediments, in contrast, cover at least 38 times more space and consequently represent the most significant carbon store in the ocean.

Worryingly, these sedimentary stores have been overlooked by the international community, without recognition in climate policy and largely left outside of marine protected areas. It is of paramount importance for us to understand how vulnerable these deposits are and how we can protect them, and we are dedicated to filling these knowledge gaps.”

OM: What have you found out so far since the Survey’s launch in 2022? Can you tell us about any exciting discoveries you’ve made to date?

GF: “Fieldwork carried out last year in Millport, Scotland has revealed the bioturbation rates of 18 different benthic species. ‘Bioturbation’ is the rate at which invertebrates that live on the seafloor mix sediment, a behaviour that can be directly linked with carbon sequestration. We discovered that highly dissimilar species, such as worms and clams, can exhibit similar influences on carbon. We have started to categorise these animals according to their functional characteristics in relation to carbon and this will lead to future estimates on their global contribution to cycling carbon.

Our data modellers have reconstructed how ocean currents have changed since the end of the last ice age, to predict carbon accumulation. This resulted in a first-of-its-kind tool – PALTIDE, which enables users to interact with any given moment or location in continental shelf ocean history over the last 20,000 years. And animated plots have been produced which depict the air-sea carbon dioxide flux for four important continental shelves, highlighting which regions act as the strongest sinks.

Working with the University of British Columbia and their Sea Around Us database, we’re developing an understanding of the spread of fisheries across the world’s continental shelves over the past 60 years, and how they disrupted seabed sediments and carbon stores as fishing efforts expanded. Our studies on ‘shifting baselines’ have revealed how human activities have eradicated native oyster reefs across Europe, altering our perception of natural seascapes. We are now turning our attention to how the seabed stores or releases carbon over different gradients of disturbance from bottom-towed fishing gears such as trawling and dredging. With all these investigations, we are incrementally adding to the evidence base, demonstrating how we can maximise the ocean’s ability to lock away carbon dioxide.”

OM: What does the Survey programme entail and how did the Blue Marine Foundation help in bringing it to life?

GF: “Broadly, in the first year, we reviewed existing literature and data sources, to understand where the big gaps in data and knowledge existed. In year two, we set out on the first field expeditions to collect empirical data, travelling to the Western Isles of Scotland, we trialled our scientific protocols and techniques, refining our methods. In years three and four, the focus is on international fieldwork, we will collect data to verify our computer models and ensure globally representative findings. In year five, we will be wrapping up data analyses, sharing results and drawing conclusions from the study. Post the survey, we will use the new knowledge generated to drive best practice and policy.”

OM: How will carbon storage in coastal seas be investigated and quantified exactly? What’s the plan?

GF: “To achieve globally representative findings we combine the use of satellite measurements, molecular techniques (eDNA), computer modelling, field expeditions and lab experiments to create a powerful, interdisciplinary package of cutting-edge science.”

OM: When can we expect to see results?

GF: “Our scientists and experts are continually conducting fieldwork and analysing findings. As this is a five-year study, results are published incrementally and starting to come through already,  but we can expect to see an abundance of results and publications coming out within the next 12-24 months.”

OM: What will these results be used for in the future? And who will be able to access them?

GF: “The results will be used to inform climate policies, enhance ocean protection and management strategies, and inform further research. All findings are open-source and freely accessible to researchers, policymakers, and the public to ensure transparency and widespread benefit.”

OM: Where will surveys take place across the globe?

GF: “Research is underway in a wide range of places, so we can extrapolate observations and measurements from particular sites to regional and global scales. Our research is being conducted across major ocean biomes, from the tropics to the poles and our regions of interest include Patagonia, Indonesia, South Africa, New Zealand, Turkey, Australia, Canada, Jersey, Scotland, and the Antarctic.”

OM: How are you trying to involve schools? Why is this important?

GF: “We have also created bespoke education programmes and immersive learning experiences with Encounter Edu to give students the knowledge and skills to tackle the world’s most pressing issues. Engaging young minds is crucial for fostering a deeper understanding of environmental issues and inspiring future generations to take action for a sustainable future.”

OM: Last but not least – how can the public get involved?

GF: “We need your help! We’re looking for healthy soft-sediment ecosystems to study, and the more information we have, the better. Anyone can participate, no specialist knowledge is required, just insight or experience with seafloor habitats anywhere in the world. We’re hoping to hear from a range of sea users, from recreational scuba divers to yachting communities and employees from offshore industries. Simply send us underwater photographs or video footage of what you believe to be healthy, intact, and undisturbed soft-sediment (muddy) seabeds.

But most importantly citizens can support the Convex Seascape Survey by advocating for ocean conservation, staying informed about our findings, participating in community science projects, and promoting sustainable practices that reduce carbon footprints. By supporting the Convex Seascape Survey, we can all become part of a vital movement; harnessing the power of our oceans to make a significant, positive impact on the global climate crisis.”


Photographs by Matt Jarvis, Henley Spiers, Michiel Vos and Shannon Moran

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