Ocean Color and Ocean Biogeochemistry

Shubha Sathyendranath
Plymouth Marine Laboratory, United Kingdom

Ocean color remains our only window into the pelagic ecosystem at synoptic scales. It is a rich source of data, and chlorophyll concentration is the principal product, which provides valuable information on how the light from the sun (the energy source for the entire ecosystem) is coupled to the marine biota through the pigments contained in phytoplankton. The absorbed energy is used by phytoplankton to produce organic carbon (marine primary production). We can combine light at the sea surface (another product available routinely using satellite data), with chlorophyll concentration from ocean color, to estimate marine primary production at the global scale, using models of light penetration, and photosynthesis. The growing list of satellite products includes phytoplankton functional types and phytoplankton size distribution. It is important to recognize that these products are not raw data. We arrive at them by combining various models with the satellite data on spectral radiance at multiple wavelengths in the visible domain, detected at the level of the satellite. Often, these models are different from, and employ different assumptions from, what is done by ecosystem models.

In this project, we propose to develop or improve novel satellite-based products, including phytoplankton functional types, particulate organic carbon, photosynthesis-irradiance parameters and phytoplankton carbon. These products, along with more standard products such as chlorophyll concentration and marine primary production, will form part of the CBIOMES data atlas. They will be used for comparison with ecosystem model outputs, and in data assimilation.

CBIOMES Collaborators in the Plymouth Group

News from the Sathyendranath Group

February 2022 CBIOMES All Hands Poster Meeting

A big THANK-YOU to everyone who presented at the February e-meeting!  (more…)

October 2021 CBIOMES e-meeting Bror Jönsson (PML)

"Estimating Export Production from Space, How Hard Can it Be?" Please note access to this page is restricted to CBIOMES associates. (more…)


Weiyi Tang, Joan Llort, Jakob Weis, Morgane M. G. Perron, Sara Basart, Zuchuan Li, Shubha Sathyendranath et al (2021), Widespread phytoplankton blooms triggered by 2019–2020 Australian wildfires, Nature, doi: 10.1038/s41586-021-03805-8 Get the PDF [Requires login]  

Shubha Sathyendranath Awarded 2021 Huntsman Medal

Warm congratulations to PML CBIOMES PI on news of her recent award. (more…)

Recordings and microtalks from the Sathyendranath Group. Please note access to this page is restricted to CBIOMES associates. (more…)


Brewin, R.J.W., Sathyendranath, S., Platt, T., Bouman, H, Ciavatta, S., Dall’Olmo, G., Dingle, J., Groom, S., Jönsson, B., Kostadinov, T.S., Kulk, G., Laine, M., Martínez-Vicente, V., Psarra, S., Raitsos, D.E., Richardson, K., Rio,...


Kovač, Ž, Platt, T, Sathyendranath, S (2021), Sverdrup meets Lambert: analytical solution for Sverdrup’s critical depth, ICES Journal of Marine Science, doi: 10.1093/icesjms/fsab013 Get the PDF [Requires login]  


Smyth, TJ, Tarran, GA, Sathyendranath, S (2021), Sub-micron picoplankton shape, orientation, and internal structure combined to preferentially amplify the forward scatter, Optics Express, doi: 10.1364/OE.413576 Get the PDF [Requires login]  

December 2020 CBIOMES (Poster) e-Meeting

To provide an opportunity to "pick up the conversation" and chat with colleagues about where work had gone since our Annual Meeting in June, the December gathering was an all-hands...

2020 Joint Simons Marine Collaborations Meeting

Please note access to this page is restricted to CBIOMES associates only. Besides CBIOMES, the Simons Foundation supports three other marine collaborations: BIOS-SCOPE, PriME, and SCOPE. A joint meeting, October...

Longer Season with Phytoplankton Growth in a Warming Arctic?

The PML-CBIOMES team led by Shubha Sathyendranath is actively engaged in developing new and improved products to extract increased detail from satellite color data. In a recent paper, they turn...


Bouman HA, Jackson T, Sathyendranath S, Platt T., (2020), Vertical structure in chlorophyll profiles: influence on primary production in the Arctic Ocean, Phil. Trans. R. Soc. A, doi: 10.1098/rsta.2019.0351 Get...


Bror F. Jönsson, Shubha Sathyendranath, Trevor Platt (2020), Trends in winter light environment over the Arctic Ocean: a perspective from two decades of ocean‐colour data, Geophysical Research Letters, doi: 10.1029/2020GL089037...

Trevor Platt (1942 – 2020) – a reflection

Director of CBIOMES Mick Follows reflects on his pick of five of Trevor Platt's papers that have illuminated the path to work underway in CBIOMES today. (more…)


Žarko Kovač, Trevor Platt, and Shubha Sathyendranath (2020), Stability and resilience in a nutrient-phytoplankton marine ecosystem model, ICES Journal of Marine Science, doi: 10.1093/icesjms/fsaa067 Get the PDF [Requires login]

The Sathyendranath Group goes to Annual meeting

  The focus of the PML-CBIOMES group is ocean color and biogeochemistry. In this video, Shubha presents an overview of current activity and advertises PML member posters. Please note access...

Measuring Climate Change

Member of the PML-CBIOMES Group Bror Jönsson has been working with Wei-Jun Cai of the University of Delaware and others on a study seeking to characterize ocean acidification throughout coastal...


Shubha Sathyendranath, Trevor Platt, Žarko Kovač, James Dingle, Thomas Jackson, Robert J. W. Brewin, Peter Franks, Emilio Marañón, Gemma Kulk, and Heather A. Bouman (2020), Reconciling models of primary production and photo-acclimation, Applied Optics, doi: 10.1364/AO.386252...

Phytoplankton: Shedding light on the ocean’s living carbon pump

Phytoplankton play a crucial role in ocean biology and climate. Understanding the natural processes that influence phytoplankton primary production, and how they are changing as the planet warms, is vital....

April 2020 CBIOMES e-meeting – Gemma Kulk (PML)

“Primary Production, an Index of Climate Change in the Ocean: Satellite-Based Estimates over Two Decades” Please note access to this page is restricted to CBIOMES associates. (more…)


Shubha Sathyendranath, Trevor Platt, Žarko Kovač, James Dingle, Thomas Jackson, Robert J. W. Brewin, Peter Franks, Emilio Marañón, Gemma Kulk, and Heather A. Bouman (2020), Reconciling models of primary production...

CBIOMES Welcomes Gemma Kulk

by Helen Hill for CBIOMES A warm welcome to postdoc Gemma Kulk who joins Shubha Sathyendranath's PML CBIOMES Group this month. (more…)

CBIOMES Goes to Ocean Sciences 2020

Look out for members of the CBIOMES team, sharing their work at this year’s Ocean Sciences conference taking place February 16-21 in San Diego, California. (more…)


T. J. Smyth, G. A. Tarran, and S. Sathyendranath (2019), Marine picoplankton size distribution and optical property contrasts throughout the Atlantic Ocean revealed using flow cytometry, Applied Optics, doi: 10.1364/AO.58.008802...

Extracting More From Ocean Color Data

Reporting by Helen Hill for CBIOMES The PML-CBIOMES team led by Shubha Sathyendranath is actively engaged in developing new and improved products to extract increased detail from satellite color data....

Recent Research in the Sathyendranath Group

by Shubha Sathyendranath for CBIOMES Please note access to this page is restricted to CBIOMES associates only. (more…)

Trends in Mediterranean Phytoplankton Phenology from Ocean-Color

by Helen Hill for CBIOMES Changes in phytoplankton Chlorophyl (Chl) and phenology (study of the phases of the phytoplankton seasonal) are key to understanding many aspects of marine community structure...

by Helen Hill for CBIOMES A warm welcome to incoming researcher Dr Bror Jönsson, a new Senior Scientist in the PML CBIOMES Group. (more…)

Past Annual Reporting

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