The importance of marine carbon

  • 19 May 2020
  • Blog

Evidence is growing of the central role that Scotland’s marine area plays in our national carbon accounts. It is estimated that 7.2 Million tonnes of carbon is buried annually in sediments in Scotland’s seas[i]. And the top 10cm of Scotland’s seabed sediment (the most vulnerable layer) stores some 5,555Mt CO2-equivalent, more than double the amount stored in the top 10 cm of Scotland’s soils and peatlands[ii].

So there is rising concern that marine carbon is missing from Scotland’s Climate Change Plan and that there is no prospect of it being included in the Plan until its 2023 revision. Until then, we must press for action on marine carbon in other ways, for example through the policies of the National Marine Plan and particularly Policy 5 which states that ‘Marine planners and decision makers must act in the way best calculated to mitigate, and adapt to, climate change’.[iii] That should mean incorporating mitigation measures in fisheries management, and increasing research: Marine Scotland has commissioned valuable work on the role of seabed sediments in carbon sequestration, but the evidence base needs expansion – for example regarding the impacts of seaweed aquaculture and the restoration of seagrass and saltmarsh habitats.

At COP25 there was much talk of ‘blue outcomes’ and the need to incorporate ocean-related options into Nationally Determined Contributions. By its close, 39 countries had committed to including oceans in their future NDCs[iv]. As a maritime nation, and the venue for COP26, Scotland should be at the forefront of such marine-related climate change action. The case for this is all the greater as the world seeks to find a way back from the coronavirus crisis: we must work to ensure that Scotland’s green recovery is shaded blue.

Charles Millar, May 2020

Charles Millar is Executive Director of the Sustainable Inshore Fisheries Trust. SIFT promotes the sustainable management of Scotland’s coastal waters and has recently joined SCCS in response to its concerns about the environmental and socio-economic threats posed by rapidly rising sea temperatures.


[i] Burrows M.T., Kamenos N.A., Hughes D.J., Stahl H., Howe J.A. & Tett P. 2014. Assessment of carbon budgets and potential blue carbon stores in Scotland’s coastal and marine environment. Scottish Natural Heritage Commissioned Report No. 761.

[ii] W R Turrell, 2020, A Compendium of Marine Related Carbon Stores, Sequestrations and Emissions, Marine Scotland Scottish Marine & Freshwater Science Vol 11 No 1

[iii] Scotland’s National Marine Plan A Single Framework for Managing Our Seas, 2015

[iv] Earth Negotiations Bulletin (ENB), Volume 12 Number 773 | Thursday, 12 December 2019