WEBINAR 4: Will the ocean uptake of anthropogenic carbon dioxide (CO₂) continue primarily as an abiotic process?
- Moderator: Richard
- 6 March 2024 | 15:30 (CET)
The ocean takes up about 25% of the carbon we emit, slowing climate change and giving us more time to put in place mitigation actions. But how does the process work and does ocean biology play a role?
OceanICU was pleased to host Judith Hauck and Jamie Shutler as they tested one of the key questions of the IOCR report in our insightful webinar.
If you missed the webinar, check out the video recording and the presentation here and scroll down for a transcript of the questions and answers.
MEET THE PANELLISTS
Richard Sanders
MODERATOR
Coordinator of the OceanICU project
Richard is the lead coordinator of the OceanICU project. He has worked since 2019 at NORCE in Bergen as Director of the Ocean Thematic Centre within the ICOS research infrastructure. This involves helping the surface ocean pCO2 observing community within Europe make the highest quality observations and in establishing more secure funding routes for surface Ocean C observations. He plans to bring this experience to support the relevant activities within EuroGO-SHIP. Prior to his move to Bergen he served as Chair of the Ocean Biogeochemistry and Ecosystems Research Group in the UK National Oceanography Centre. He holds an honorary chair in Ocean Biogeochemistry at the University of Southampton in the UK.
Judith Hauck
Head of Helmholtz Young Investigator Group for Marine Carbon and Ecosystem Feedbacks in the Earth System (MarESys), and Deputy Head of Marine Biogeosciences at the Alfred Wegener Institute.
Judith is the deputy lead of the Marine Biogeosciences section at AWI and coordinates the ocean carbon sink estimate in the Global Carbon Budget. She leads the development and application of the ocean biogeochemistry model REcoM and investigates the ocean carbon cycle in the polar regions and globally, as well as its physical and biological drivers.
She currently leads the Helmholtz Young Investigator Group Marine Carbon and Ecosystem Feedbacks in the Earth System as well as the ERC Starting Grant project The global ocean carbon cycle after peak emissions. She has participated and is currently participating in multiple EU projects, as PI or WP lead, e.g. COMFORT, OceanNETs, OceanICU, POMP. She is on the Scientific Steering Committee of the RECCAP Regional Carbon Cycle Assessment and Processes project phase 2, and involved in working and advisory groups on ocean carbon, e.g., IOC-R, G7 FSOI, WMO GGGW.
Jamie Shutler
Professor of Earth Observation and Climate, University of Exeter
Jamie is an ocean and atmospheric scientist with a wide range of interests that exploit satellite Earth observation, in situ observations and models to study and monitor land, water and atmosphere environments and interactions, particularly in relation to climate. This includes studying atmosphere-ocean exchange of climatically important gases, carbon accounting, bacterial, biological, viral and chemical water quality and land-water continuum interactions. His work has covered novel in situ monitoring methods to support aquaculture, through to global analyses of carbon to support policy, through to the design of satellites for the European Space Agency. I was an invited scientific reviewer for the Intergovernmental Panel on Climate Change (IPCC) Special Report on the Oceans and Cryosphere in a Changing Climate (SROCC), and was a lead author for the United Nations Educational, Scientific and Cultural Organisation (UNESCO) and International Oceanographic Commission (IOC) decadal vision for integrated ocean carbon research.
His research has been featured in the Guardian Environment, BBC news, Al Jazeera TV, Forbes, Higgs, The Daily Mail, The World Economic Forum, contributed to UK parliamentary enquiries (Ocean Acidification, 2017; Sustainable Seas, 2018) and guided international and inter-governmental agencies and research programmes.
Questions from the audience
Answered by Judith Hauck
I think the answer is yes. I would not have an answer on how big the effect is, but it’s been coming up again and again, also in questions of consistency of carbonate system measurements. So I think the community is still exploring the size of this effect (organic alkalinity), but others in the audience might have more to say on this topic.
So I guess there’s multiple aspects in this question. We’ve had a meta analysis looking at the indirect effects of temperature, nutrients, acidification on phytoplankton growth (Seifert et al., 2020). And what we found is that actually both warming and pCO2 (partial pressure of CO2) were to increase that would have positive effects on phytoplankton growth, of course, but only until a certain optimum is reached and there would be negative effects afterwards. But the interplay of the two changes the overall response: the pCO2 increase would actually dampen the otherwise positive effects of warming. And yes, that’s what we found there.
I think these interactions of changing environmental drivers are not sufficiently included in the current state of the existing models. There are many reasons why we should understand this: What does it mean for primary production? What does it mean for ecosystems? What does it mean for food webs? That probably matters more than what it means for carbon cycling.
Well, in terms of global ocean primary production, I think plankton is the major player and macroalgae only contribute a very small part. So I would be skeptical that we can upscale any macroalgae production to a level that it can really compensate to a significant percentage human CO2 emissions. But also that is an active area of research. And clearly there are very different views out there in the community
Answered by Jamie Shutler
This Pole-ward movement that’s being observed, when I say pole ward movement, they’re moving from mid-latitudes to the pole and that has been documented. It was theorized that they were moving. And then more recently we’ve seen evidence that they all have been observed to move and they can then grow. They actually take up carbon dioxide, but they also push it back out into the water. And so they have the impact of reducing the amount of carbon uptake that the water can achieve. This current work also is showing that the temperature as well, which is linked to solubility, also means that they alter the amount of carbon that can be absorbed. So yes and certainly some of my early work showed that it can be up to 155% reduction in the ocean depending on where they occur when they occur.
So they can have a significant impact and it is something that is a project and large projects being run of the UK, I think by Alex Poulton, who’s actually online today, he’s his studies looking at these impacts music now how strong can they be? And this is, I think for me this is a big area where they can go to the alkilinty and links back to what I was talking about, the fact that this is going to become more important for governing the uptake of carbon.
Reading List
Seifert, M.; Rost, B.; Trimborn, S.; Hauck, J. Meta‐analysis of Multiple Driver Effects on Marine Phytoplankton Highlights Modulating Role of p CO 2. Glob. Change Biol. 2020, 26 (12), 6787–6804. https://doi.org/10.1111/gcb.15341.
Shutler, J.D., Land, P.E., Brown, C.W., Findlay, H.S., Donlon, C.J., Medland, M., Snooke, R. and Blackford, J.C., 2013. Coccolithophore surface distributions in the North Atlantic and their modulation of the air-sea flux of CO 2 from 10 years of satellite Earth observation data. Biogeosciences, 10(4), pp.2699-2709.
Shutler, J.D., Gruber, N., Findlay, H.S., Land, P.E., Gregor, L., Holding, T., Sims, R.P., Green, H., Piolle, J.F., Chapron, B. and Sathyendranath, S., 2024. The increasing importance of satellite observations to assess the ocean carbon sink and ocean acidification. Earth-Science Reviews, 250, p.104682