Stephen Calvert
Professor emeritus

B.Sc.: Reading (1958)
Ph.D.: California - Scripps Institution of Oceanography (1964) (Supervisors: Tj. H. van Andel and E.D. Goldberg)



Research Interests

The long-term goal of my research is to understand the factors responsible for the wide compositional variability of marine sediments, the controls on organic matter burial and nutrient utilization in the ocean, and to use this information to interpret past oceanographic and climatic changes from sediment core records. Specifically, I am examining:

1. Holocene climate variability along the northeastern Pacific coast at decadal and centennial resolution;
2. Millennial variability of oceanographic and climatic conditions in the northeastern Arabian Sea and their relationship to the high-resolution ice core records from Greenland and Antarctica;
3. The influence of changes in monsoon strength in the South China Sea on terrestrial climate and ocean conditions;
4. Glacial-interglacial palaeoceanographic records of variations in upwelling, nutrient utilization and carbon accumulation on the California continental margin.

A combination of organic, inorganic and stable isotopic information is used to reconstruct past sea surface temperatures, plankton production, terrestrial sediment supply and transport modes, nutrient utilization and bottom water oxygen concentrations.

Selected Recent Publications

Ganeshram, R. S., T. F. Pedersen, Calvert, S.E., and Francois, R.,(2002). Reduced nitrogen fixation in the glacial ocean inferred from changes in marine nitrogen and phosphorus inventories. Nature, 415: 156-159.

Calvert, S. E. and M. R. Fontugne (2001). On the late Pleistocene-Holocene sapropel record of climatic and oceanographic variability in the eastern Mediterranean. Paleoceanography, 16(1): 78-94.

Schubert, C. J. and S. E. Calvert (2001). Nitrogen and carbon isotopic composition of marine and terrestrial organic matter in Arctic Ocean sediments: implications for nutrient utilization and organic matter composition. Deep-Sea Research Part II, 48: 789-810.

Kienast, M., Steinke, S., Stattegger, K. and Calvert, S.E., (2001), Synchronous tropical South China Sea surface temperature change and Greenland warming during deglaciation, Science, 291: 2132-2134.

Calvert, S. E., T. F. Pedersen, and R.F. Karlin, (2001).,Geochemical and isotopic evidence for post-glacial palaeoceanographic changes in Saanich Inlet, British Columbia. Marine Geology, 174: 287-305.

Kienast, M., Calvert, S.E., Pelejero, C. and Grimalt, J., (2001), A critical review of marine sedimentary d13Corg-pCO2 estimates: New paleo-records from the South China Sea and a revisit of other low-latitude d13Corg-pCO2 records, Global Biogeochemical Cycles, 15: 113-127.

Schubert, C. J., R. Stein, and S. E. Calvert, (2001). Tracking nutrient and productivity variations over the last deglaciation in the Arctic Ocean. Paleoceanography, 16(2): 199-211.

Ganeshram, R.S., Pedersen, T.F., Calvert, S.E., McNeill, G.W. and Fontugne, M.R., (2000), Glacial-interglacial variability in denitrification in the World's oceans: Causes and consequences, Paleoceanography, 15: 361-376

Martinez, P., Bertrand, P., Calvert, S.E., Pedersen, T.F., Shimmield, G.B and Lallier-Verges, E., (2000). "Spatial variations in nutrient utilization, production and diagenesis in sediments of a coastal upwelling regime (NW Africa) -Implications for the palaeoceanographic record", Journal of Marine Research, 58: 809-835.

Ganeshram, R. S., S. E. Calvert, Pedersen, T.F., and Cowie, G.L. (1999). Factors controlling the burial of organic carbon in laminated and bioturbated sediments off NW Mexico: Implications for hydrocarbon preservation. Geochim. et Cosmochim. Acta, 63(11/12): 1723-1734.

Wu, J., S. E. Calvert, C.S. Wong, and F. Whitney, (1999). Carbon and nitrogen isotopic composition of sedimenting particulate material at Station Papa in the subarctic northeast Pacific. Deep Sea Research, Part II: 46,2793-2832

Waser, N. A., Z. Yu, K. Yin, B. Nielsen, P. J. Harrison, D. H. Turpin, S. E. Calvert (1999). Nitrogen isotopic fractionation during a simulated diatom spring bloom: importance of N-starvation in controlling fractionation. Marine Ecology Progress Series, 179: 291-296.

Schubert, C. J., J. Villanueva, S E Calvert, U. von Rad, H. Schulz, U. Berner, H. Erlenkeuser (1998). Stable phytoplankton community structure in the Arabian Sea over the past 200,000 years. Nature, 394: 563-566.

Calvert, S. E. and R. E. Karlin (1998). Organic carbon accumulation in the Holocene sapropel of the Black Sea. Geology, 26: 107-110

last updated August 7, 2002