Ocean and Earth Science, National Oceanography Centre Southampton

Toby Tyrrell

BSc, MSc, PhD

Primary position:
Professor in Earth System Science


The University of Southampton
Professor Toby Tyrrell's photo

BSc Civil Engineering, Southampton University (1988)
MSc Artificial Intelligence, Edinburgh University (1989)
PhD Edinburgh University (1993)

Fellow of the Challenger Society for Marine Science
Member of the American Geophysical Union
Fellow of the Geological Society



Tyrrell, Toby (2013) On Gaia: A Critical Investigation of the Relationship between Life and Earth, Princeton, US, Princeton University Press, 312pp..

The University of Southampton's electronic library (e-prints)


Fry, Claudia H., Tyrrell, Toby, Hain, Mathis P., Bates, Nicholas R. and Achterberg, Eric P. (2015) Analysis of global surface ocean alkalinity to determine controlling processes. Marine Chemistry, 174, 46-57. (doi:10.1016/j.marchem.2015.05.003).
Hopkins, Jason, Henson, Stephanie A., Painter, Stuart C., Tyrrell, Toby and Poulton, Alex J. (2015) Phenological characteristics of global coccolithophore blooms. Global Biogeochemical Cycles, 29, (2), 239-253. (doi:10.1002/2014GB004919).
Tyrrell, Toby, Merico, Agostino and Armstrong McKay, David I. (2015) Severity of ocean acidification following the end Cretaceous asteroid impact. Proceedings of the National Academy of Sciences, 112, (21), 6556- 6561. (doi:10.1073/pnas.1418604112).
Armstrong McKay, David I., Tyrrell, Toby, Wilson, Paul A. and Foster, Gavin L. (2014) Estimating the impact of the cryptic degassing of Large Igneous Provinces: A mid-Miocene case-study. Earth and Planetary Science Letters, 403, 254-262. (doi:10.1016/j.epsl.2014.06.040).
Richier, S., Achterberg, E.P., Dumousseaud, C., Poulton, A.J., Suggett, D.J., Tyrrell, T., Zubkov, M.V. and Moore, C.M. (2014) Phytoplankton responses and associated carbon cycling during shipboard carbonate chemistry manipulation experiments conducted around Northwest European shelf seas. Biogeosciences, 11, (17), 4733-4752. (doi:10.5194/bg-11-4733-2014).
Ribas-Ribas, M., Rérolle, V.M.C., Bakker, D.C.E., Kitidis, V., Lee, G.A., Brown, I., Achterberg, E.P., Hardman-Mountford, N.J. and Tyrrell, T. (2014) Intercomparison of carbonate chemistry measurements on a cruise in northwestern European shelf seas. Biogeosciences, 11, (16), 4339-4355. (doi:10.5194/bg-11-4339-2014).
MacGilchrist, G.A., Shi, T., Tyrrell, T., Richier, S., Moore, C.M., Dumousseaud, C. and Achterberg, E.P. (2014) Effect of enhanced pCO2 levels on the production of dissolved organic carbon and transparent exopolymer particles in short-term bioassay experiments. Biogeosciences, 11, (13), 3695-3706. (doi:10.5194/bg-11-3695-2014).
Jiang, Zong-Pei, Tyrrell, Toby, Hydes, David J., Dai, Minhan and Hartman, Susan E. (2014) Variability of alkalinity and the alkalinity-salinity relationship in the tropical and subtropical surface ocean. Global Biogeochemical Cycles, 28, (7), 729-742. (doi:10.1002/2013GB004678).
Young, J.R., Poulton, A.J. and Tyrrell, T. (2014) Morphology of Emiliania huxleyi coccoliths on the North West European shelf – is there an influence of carbonate chemistry? Biogeosciences Discussions, 11, (3), 4531-4561. (doi:10.5194/bgd-11-4531-2014).
Tyrrell, T. and Achterberg, E.P. (2014) Preface: Field investigation of ocean acidification effects in northwest European seas. Biogeosciences, 11, (24), 7269-7274. (doi:10.5194/bg-11-7269-2014).
Daniels, C.J., Tyrrell, Toby, Poulton, A.J. and Young, J.R. (2014) A mixed life-cycle stage bloom of Syracosphaera bannockii (Borsetti and Cati, 1976) Cros et al. 2000 (Bay of Biscay, April 2010). [in special issue: Coccolithophores 2014 Workshop Volume] Journal of Nannoplankton Research, 34, 31-35.
Tyrrell, Toby (2013) Gaia: the verdict is... The New Scientist, 220, (2940), 30-31.
Jiang, Zong-Pei, Hydes, David J., Tyrrell, Toby, Hartman, Sue, Hartman, Mark C., Dumousseaud, Cynthia, Padin, Xose Antonio, Skjelvan, Ingunn and González-Pola, César (2013) Key controls on the seasonal and interannual variations of the carbonate system and air-sea CO2 flux in the Northeast Atlantic (Bay of Biscay). Journal of Geophysical Research, 118, (2), 785-800. (doi:10.1002/jgrc.20087).
Smith, H.E.K., Tyrrell, T., Charalampopoulou, A., Dumousseaud, C., Legge, O.J., Birchenough, S., Pettit, LR., Garley, R., Hartman, S.E., Hartman, M.C., Sagoo, N., Daniels, C.J., Achterberg, E.P. and Hydes, D.J. (2012) Predominance of heavily calcified coccolithophores at low CaCO3 saturation during winter in the Bay of Biscay. Proceedings of the National Academy of Sciences, 109, (23), 8845-8849. (doi:10.1073/pnas.1117508109).
Loucaides, Socratis, Tyrrell, Toby, Achterberg, Eric P., Torres, Ricardo, Nightingale, Philip D., Kitidis, Vassilis, Serret, Pablo, Woodward, Malcolm and Robinson, Carol (2012) Biological and physical forcing of carbonate chemistry in an upwelling filament off northwest Africa: Results from a Lagrangian study. Global Biogeochemical Cycles, 26, (3), GB3008. (doi:10.1029/2011GB004216).
Daniels, Chris J., Tyrrell, Toby, Poulton, Alex J. and Pettit, Laura (2012) The influence of lithogenic material on particulate inorganic carbon measurements of coccolithophores in the Bay of Biscay. Limnology and Oceanography, 57, (1), 145-153. (doi:10.4319/lo.2012.57.1.0145).
Tyrrell, T. (2011) Anthropogenic modification of the oceans. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 369, (1938), 887-908. (doi:10.1098/rsta.2010.0334).
Charalampopoulou, Anastasia, Poulton, Alex J., Tyrrell, Toby and Lucas, Mike I. (2011) Irradiance and pH affect coccolithophore community composition on a transect between the North Sea and the Arctic Ocean. Marine Ecology Progress Series, 431, 25-43. (doi:10.3354/meps09140).
Tyrrell, Toby, Loucaides, Socratis, Kelly-Gerreyn, Boris and Achterberg, Eric (2010) Interactive comment on “On CO2 pertubation experiments: over-determination of carbonate chemistry reveals inconsistencies” by C.J.M. Hoppe et al. Biogeosciences Discussions, 7, C257 .
Dumousseaud, C., Achterberg, E.P., Tyrrell, T., Charalampopoulou, A., Schuster, U., Hartman, M. and Hydes, D.J. (2010) Contrasting effects of temperature and winter mixing on the seasonal and inter-annual variability of the carbonate system in the Northeast Atlantic Ocean. Biogeosciences, 7, (5), 1481-1492. (doi:10.5194/bg-7-1481-2010).
Bernie, D., Lowe, J., Tyrrell, T. and Legge, O. (2010) Influence of mitigation policy on ocean acidification. Geophysical Research Letters, 37, (15), L15704. (doi:10.1029/2010GL043181).
Hauton, C., Tyrrell, T. and Williams, J. (2009) The subtle effects of sea water acidification on the amphipod Gammarus locusta. Biogeosciences, 6, (8), 1479-1489. (doi:10.5194/bg-6-1479-2009).
Zeebe, R.E., Zachos, J.C., Caldeira, K. and Tyrrell, T. (2008) Carbon emissions and acidification. Science, 321, (5885), 51-52. (doi:10.1126/science.1159124).
Iglesias-Rodriguez, M. Debora, Halloran, Paul R., Rickaby, Rosalind E. M., Hall, Ian R., Colmenero-Hidalgo, Elena, Gittins, John R., Green, Darryl R. H., Tyrrell, Toby, Gibbs, Samantha J., von Dassow, Peter, Rehm, Eric, Armbrust, E. Virginia and Boessenkool, Karin P. (2008) Phytoplankton calcification in a high-CO2 world. Science, 320, (5874), 336-340. (doi:10.1126/science.1154122).
Tyrrell, T. (2008) Calcium carbonate cycling in future oceans and its influence on future climates. Journal of Plankton Research, 30, (2), 141-156. (doi:10.1093/plankt/fbm105).
Tyrrell, T., Schneider, B., Charalampopoulou, A. and Riebesell, U. (2008) Coccolithophores and calcite saturation state in the Baltic and Black Seas. Biogeosciences, 5, (2), 485-494.
Findlay, H.S., Tyrrell, T., Bellerby, R. G. J., Merico, A. and Skjelvan, I. (2008) Carbon and nutrient mixed layer dynamics in the Norwegian Sea. Biogeosciences, 5, (5), 1395-1410.
Tyrrell, Toby, Shepherd, John G. and Castle, Stephanie (2007) The long-term legacy of fossil fuels. Tellus B, 59, (4), 664-672. (doi:10.1111/j.1600-0889.2007.00290.x).
Raitsos, D.E., Lavender, S.J., Pradhan, Y., Tyrrell, T., Reid, P.C. and Edwards, M. (2006) Coccolithophore bloom size variation in response to the regional environment of the subarctic North Atlantic. Limnology and Oceanography, 51, (5), 2122-2130.
Hoogakker, B.A.A., Rohling, E.J., Palmer, M.R., Tyrrell, T. and Rothwell, R.G. (2006) Underlying causes for long-term global ocean d13C fluctuations over the last 1.2 Ma. Earth and Planetary Science Letters, 248, (1), 15-29. (doi:10.1016/j.epsl.2006.05.007).
Merico, A., Tyrrell, T. and Cokacar, T. (2006) Is there any relationship between phytoplankton seasonal dynamics and the carbonate system? Journal of Marine Systems, 59, (1-2), 120-142. (doi:10.1016/j.jmarsys.2005.11.004).
Tyrrell, T., Merico, A., Waniek, J.J., Wong, C.S., Metzl, N. and Whitney, F. (2005) Effect of seafloor depth on phytoplankton blooms in high-nitrate, low-chlorophyll (HNLC) regions. Journal of Geophysical Research, 110, (G2), G02007-[12pp]. (doi:10.1029/2005JG000041).
Lessard, E.J., Merico, A. and Tyrrell, T. (2005) Nitrate: phosphate ratios and Emiliania huxleyi blooms. Limnology and Oceanography, 50, (3), 1020-1024.
Yool, A. and Tyrrell, T. (2005) Implications for the history of Cenozoic opal deposition from a quantitative model. Palaeogeography, Palaeoclimatology, Palaeoecology, 218, (3-4), 2005. (doi:10.1016/j.palaeo.2004.12.017).
Tyrrell, T. and Zeebe, R.E. (2004) History of carbonate ion concentration over the last 100 million years. Geochimica et Cosmochimica Acta, 68, (17), 3521-3530. (doi:10.1016/j.gca.2004.02.018).
Smyth, T.J., Tyrrell, T. and Tarrant, B. (2004) Time series of coccolithophore activity in the Barents Sea, from twenty years of satellite imagery. Geophysical Research Letters, 31, (11), L11302. (doi:10.1029/2004GL019735).
Merico, A., Tyrrell, T., Lessard, E.J., Oguz, T., Stabeno, P.J., Zeeman, S.I. and Whitledge, T.E (2004) Modelling phytoplankton succession on the Bering Sea shelf: role of climate influences and trophic interactions in generating Emiliania huxleyi blooms 1997-2000. Deep Sea Research Part I: Oceanographic Research Papers, 51, (12), 1803-1826. (doi:10.1016/j.dsr.2004.07.003).
Lampitt, Richard S., Popova, Ekaterina E. and Tyrrell, Toby (2003) Biogeochemical evidence of vigorous mixing in the abyssal ocean. Geophysical Research Letters, 30, (9), 1459-1462. (doi:10.1029/2002GL016638).
Yool, A. and Tyrrell, T. (2003) The role of diatoms in regulating the ocean's silicon cycle. Global Biogeochemical Cycles, 17, (4), 1-21. (doi:10.1029/2002GB002018).
Tyrrell, T., Maranon, E., Poulton, A.J., Bowie, A.R., Harbour, D.S. and Woodward, E.M.S. (2003) Large-scale latitudinal distribution of Trichodesmium spp. in the Atlantic Ocean. Journal of Plankton Research, 25, (4), 405-416.
Merico, A., Tyrrell, T., Brown, C.W., Groom, S.B. and Miller, P.I. (2003) Analysis of satellite imagery for Emiliania huxleyi blooms in the Bering Sea before 1997. Geophysical Research Letters, 30, (6), art. no.1337. (doi:10.1029/2002GL016648).
Broerse, A.T.C., Tyrrell, T., Young, J.R., Poulton, A.J., Merico, A., Balch, W.M. and Miller, P.I. (2003) The cause of bright waters in the Bering Sea in winter. Continental Shelf Research, 23, (16), 1579-1596. (doi:10.1016/j.csr.2003.07.001).
Tyrrell, T. and Lucas, M.I. (2002) Geochemical evidence of denitrification in the Benguela upwelling system. Continental Shelf Research, 22, (17), 2497-2511. (doi:10.1016/S0278-4343(02)00077-8).
Smyth, T.J., Land, P.E., Groom, S.B., Moore, G.F. and Tyrrell, T. (2002) Optical modelling and measurements of a coccolithophore bloom. Applied Optics, 41, (36), 7679-7688.
Tyrrell, T. and Wright, J. (2001) Calcium carbonate and climate. Ocean Challenge, 11, (1), 13-21.
Groom, S. and Tyrrell, T. (2000) Plankton summer blooms. Ocean Zone, Southampton Oceanography Centre, No.2, p.6.
Tyrrell, T. and Law, C.S. (1997) Low nitrate: phosphate ratios in the global ocean. Nature, 387, (6635), 793-796.


Tyrrell, Toby (2013) On Gaia: A Critical Investigation of the Relationship between Life and Earth, Princeton Meadows, US, Princeton University Press, 320pp.

Book Section

Tyrrell, T. and Young, J.R. (2009) Coccolithophores. In, Steele, John H., Turekian, Karl K. and Thorpe, Steve A. (eds.) Encyclopedia of Ocean Sciences, 2nd ed. San Diego, US, Academic Press, 3568-3576.
Tyrrell, T. (2004) Biotic plunder: control of the environment by biological exhaustion of resources. In, Schneider, S.H., Miller, J.R., Crist, E. and Boston, P.J. (eds.) Scientists debate Gaia: the next Century. Cambridge MA, USA, MIT Press, 137-147.
Tyrrell, T. and Merico, A. (2004) Emiliania huxleyi: bloom observations and the conditions that induce them. In, Thierstein, H.R. and Young, J.R. (eds.) Coccolithophores: from molecular processes to global impact. Berlin, Germany, Springer, 75-97.
Tyrrell, T. (2001) Redfield ratio. In, Steele, John H., Thorpe, Steve A. and Turekian, Karl K. (eds.) Encyclopedia of Ocean Sciences. San Diego, USA, Academic Press, 2377-2387.


Legge, O. and Tyrrell, T. (2010) Short Report on Results of Acidification Modelling Study. Southampton, GB, University of Southampton, School of Ocean and Earth Sciences
Hydes, D.J., Loucaides, S. and Tyrrell, T. (2010) Report on a desk study to identify likely sources of error in the measurements of carbonate system parameters and related calculations, particularly with respect to coastal waters and ocean acidification experiments. Supplement to DEFRA contract ME4133 “DEFRApH monitoring project”. Southampton, UK, National Oceanography Centre Southampton, 53pp. (National Oceanography Centre Southampton Research and Consultancy Report, 83).
Legge, O. and Tyrrell, T. (2009) Short review of chemical and biological consequences of ocean acidification. Southampton, GB, University of Southampton School of Ocean and Earth Sciences


Research Interests

Specialism: Ocean acidification

How organisms interact with their environments. Ecology of phytoplankton, coccolithophores in particular. Ocean acidification. Ocean biogeochemistry, including during extreme events in Earth’s ancient past such as the E/O and K/T boundaries. Ocean carbon cycle and its effect on future atmospheric CO2 levels. Marine cycles of N, P, C, Si. The control of biogenic element concentrations in the sea as a function of ecological competition between different functional groups of phytoplankton.

PhD Supervision

Dave Mackay, Claudia Fry, Christopher Daniels, Matthew Humphreys, Pippa Hayes, Lucie Munns, Kyle Mayers, Charlotte Walker, Jennifer Clarke.

Primary research group:  Marine Biogeochemistry

Research projects

UK ocean acidification impacts on the surface ocean (UKOARP)

Swire NOCS Ocean Monitoring System (SNOMS)

Past and Present Ocean Acidification

Understanding changes in Cenozoic carbonate chemistry

RAGNARoCC: Radiatively active gases from the North Atlantic Region and Climate Change


Head of Marine Biogeochemistry Group
Leader of NOCS Beacon Theme on Ocean Acidification
Coordinator of the sea-surface consortium, a major component (>£3m, 10 partner institutions) of the United Kingdom Ocean Acidification Research Programme.

Teaching Responsibilities

Coordinator of SOES3011 Biogeochemical Cycles in the Earth System
Coordinator of SOES3042 Computational Data Analysis


Professor Toby Tyrrell
Ocean and Earth Science, National Oceanography Centre Southampton University of Southampton Waterfront Campus European Way Southampton SO14 3ZH United Kingdom

Room Number: NOCS/164/05

Telephone: (023) 8059 6110
Facsimile: (023) 8059 3059
Email: Toby.Tyrrell@soton.ac.uk