Francisco de Melo Virissimo
Francisco de Melo Virissimo is a researcher at the London School of Economics, as part of their Grantham Research Institute on Climate Change and the Environment. His work sits at the interface of mathematics and environmental sciences, where he combines data and modelling approaches to study the ocean and climate phenomena - with a particular interest in the ocean's biological carbon pump. After graduating with BSc, MSc and PhD in Mathematics, he moved into environmental sciences, first as a marine biogeochemist at the UK's National Oceanography Centre, before taking on his current role at LSE. He has since expanded his remit to incorporate social and economic aspects of the oceans and climate as well - currently co-leading a major climate adaptation project, which bridges climate science with private-sector investment in UK climate adaptation through the application of physical climate storylines in the context of adaptation finance.
He has held visiting positions at international institutions, including at the University of Sao Paulo's interdisciplinary Climate Investigation Centre, where in 2020 he created and taught the world's first postgraduate module dedicated to the mathematical and computational modelling of marine biogeochemical cycles, teaching ~100 postgraduate over five cohorts (2020-2025) and organising several international early-career, student-led symposia as part of it.
His work has received multiple national and international awards, including the 2024 STEM for BRITAIN Award in the Houses of Parliament for "excellence of mathematical research on climate", and more recently the 2026 Arne Richter Award for Outstanding Early-Career Scientists by the European Geosciences Union (EGU).
In addition, he is a highly active member of the community, having organised several events, and served in committees and other roles in professional and learned societies in his areas of expertise. His involvement with ICES, in particular, started in 2021, serving as ToR leader of the ICES' SIIECS initiative between 2021 and 2023.
Does seasonality matter? Unravelling the seasonality of the biological carbon pump and its consequences for carbon sequestration in the ocean
The biological carbon pump (BCP) comprises a suite of intertwined physical, ecological and biogeochemical processes that collectively transport billions of tonnes of carbon annually from the surface into the deep ocean. This process starts with photosynthesised particulate organic carbon (POC) sinking from the surface ocean (upper ~100m) into the mesopelagic zone, where it is progressively remineralised. As this downward flux of POC is attenuated, only a small fraction ultimately reaches the bathypelagic depths (below ~1,000 m), where it can remain isolated from the atmosphere for hundreds of years.
Despite some significant progress made in the field over the past 50 years, several open questions and uncertainties remain about the BCP functioning and its impacts. A major one is related to the efficiency of the aforementioned POC transfer, which is considered an important factor in regulating the air-sea CO₂ balance. Although this POC transfer efficiency is known to vary geographically across the ocean, the reasons behind this variability are still uncertain, with different studies reporting contrasting results. Central to these attempts to explain spatial variability is that they assume that the POC flux attenuation is temporally steady, despite growing evidence that it varies substantially across seasons. This poses a question - does this seasonal variability matter?
Answering to this question, this keynote will focus on the emerging importance of seasonality in shaping the biological carbon pump. Drawing on new observational analyses and modelling results, Fransisco will show how seasonal variations in carbon attenuation fundamentally reorganise global patterns of deep-ocean carbon transfer. In particular, the keynote will demonstrate that seasonal variability alone can explain regional differences in the efficiency of carbon transfer, providing a unifying mechanism behind previously conflicting interpretations, and offering fresh insights into the BCP's role in long-term carbon storage and climate regulation. Fransisco will then discuss some of the caveats and future directions for this study, as well as the implications for the BCP in a changing climate.
In addition to presenting the scientific advances and a brief historical and methodological perspective, Fransisco will reflect on how his own rather unconventional career path has shaped the way he approaches problems that bridge ecology, biogeochemistry, climate, and modelling. Fransisco will also discuss the essential role of professional and learned societies and community-led organisations, including ICES Strategic Initiative on Integration of Early Career Scientists (SIIECS), in his development as a researcher, collaborator, and member of the ocean science community.
The keynote speaker will keep the talk self-contained to allow for a broad participation and discussion – so anyone with an interest or curiosity about this subject is encouraged to join!
