Tom Marchitto

Tom Marchitto

Fellow of INSTAAR

  • Professor, Dept. of Geological Sciences
  • Affiliate Faculty, Dept. of Atmospheric and Oceanic Sciences
  • Associate Editor, Geochimica et Cosmochimica Acta



  • PhD: Marine Geology and Geophysics, MIT-Woods Hole Oceanographic Institution Joint Program, 1999
  • BS: Geology and Geophysics, Yale University, 1994

Contact Information

(Office) 303 492-7739


Paleoceanography and paleoclimatology
ICP-MS Trace Metal Lab

Research Interests

Past abrupt climate change, ocean circulation, ocean biogeochemistry, marine carbon cycle, trace and minor elements in biogenic calcium carbonates, biomineralization

Tom Marchitto on Google Scholar


Graduate students assist with retrieval of a gravity core aboard the R/V Knorr in the Florida Straits. This coring device is useful for obtaining records of relatively recent climate, typically spanning some tens of thousand of years. Photo credit: Tom Marchitto.

As human activities continue to alter Earth’s climate, it becomes increasingly important to look to the past to better understand the future. I am a paleoceanographer, studying large-scale changes in ocean circulation and biogeochemistry that occur over timescales ranging from a few years to millions of years. Major variations in ocean circulation, from the surface to abyssal depths, have influenced climate via the transport and storage of heat. The oceans also exert control over atmospheric levels of carbon dioxide, an important greenhouse gas. Such changes are reflected in the physical and chemical properties of seawater, including temperature, salinity, carbonate chemistry, radiocarbon age, and the concentrations of various nutrients. I use the chemistry of marine calcifiers, mainly foraminifera, as recorders of these properties.

I grew up in the geologically fascinating state of Connecticut, and was the first member of my family to attend college. As collecting minerals and fossils were favorite hobbies of my youth, I decided to major in geology at Yale University. I did undergraduate research with geochemist Karl Turekian and micropaleontologist Kuo-Yen Wei. It was only natural to combine these two fields in my pursuit of a PhD in the MIT – Woods Hole Oceanographic Institution Joint Program. My principal advisors there were paleoceanographers Bill Curry and Delia Oppo, while Ed Boyle was also an important mentor. I then spent a bit over three years at the Lamont-Doherty Earth Observatory, working with a tremendous group of scientists that included my post-doctoral advisor Jean Lynch-Stieglitz, Lex van Geen, Peter deMenocal, Gerard Bond, Sidney Hemming, and Wally Broecker. I have been teaching at CU Boulder since 2003.


  • College Scholar Award, University of Colorado Boulder, 2017
  • Kavli Frontiers of Science Fellow, National Academy of Sciences, 2013
  • Provost's Faculty Achievement Award, University of Colorado Boulder, 2008


Research Statement

Paleoceanographers deploy a multicorer aboard the R/V Knorr in the Florida Straits. This coring device is designed to capture multiple undisturbed samples of the sediment-water interface. Photo credit: Tom Marchitto.

Recent and ongoing research has revolved around these NSF-funded projects:

Development of individual foraminiferal Mg/Ca to reconstruct past ENSO variability
PI: Tom Marchitto (2016-2018)

A visual system for autonomous foraminifera identification
Collaborative PIs: Edgar Lobaton, Tom Marchitto (2016-2018)

Automating reasoning in interpreting climate records of the past
PI: Liz Bradley; co-PIs: Ken Anderson, Tom Marchitto, Jim White (2012-15)

Investigation of a dynamical response of the tropical Pacific to orbital and solar forcing during the Holocene
PI: Tom Marchitto (2011-14)

Active Research

Research Programs

Research Labs and Groups



Brigitta RongstadTom Marchitto, Serrato Marks, G., Koutavas, A., Mekik, F., Ravelo, A. C. 2020: Investigating ENSO‐related temperature variability in equatorial Pacific core‐tops using Mg/Ca in individual planktic foraminifera. Paleoceanography and Paleoclimatology, accepted. DOI: 10.1029/2019PA003774

Piasecki, A., Bernasconi, S. M., Grauel, A.-L., Hannisdal, B., Ho, S. L., Leutert, T. J., Tom Marchitto, Meinicke, N., Tisserand, A., Meckler, N. 2019: Application of clumped isotope thermometry to benthic foraminifera. Geochemistry, Geophysics, Geosystems, 20(4): 2082-2090. DOI: 10.1029/2018GC007961

Mitra, R., Tom Marchitto, Ge, Q., Zhong, B., Kanakiya, B., Cook, M. S., Fehrenbacher, J. S., Ortiz, J. D., Tripati, A., Lobaton, E. 2019: Automated species-level identification of planktic foraminifera using convolutional neural networks, with comparison to human performance. Marine Micropaleontology, 147: 16-24. DOI: 10.1016/j.marmicro.2019.01.005

Waelbroeck, C., and 62 others including, Tom Marchitto 2019: Consistently dated Atlantic sediment cores over the last 40 thousand years. Scientific Data, 6: article 165. DOI: 10.1038/s41597-019-0173-8

Valley, S. G., Lynch-Stieglitz, J., Tom Marchitto 2019: Intermediate water circulation changes in the Florida Straits from a 35 ka record of Mg/Li-derived temperature and Cd/Ca-derived seawater cadmium. Earth and Planetary Science Letters, 523: 115692. DOI: 10.1016/j.epsl.2019.06.032

Tom Marchitto, Bryan, S. P., Whitney Doss, McCulloch, M. T., Montagna, P. 2018: A simple biomineralization model to explain Li, Mg, and Sr incorporation into aragonitic foraminifera and corals. Earth and Planetary Science Letters, 481: 20-29. DOI: 10.1016/j.epsl.2017.10.022

Oppo, D. W., Gebbie, G., Huang, K.-F., Curry, W. B., Tom Marchitto, Pietro, K. 2018: Data constraints on glacial Atlantic water mass geometry and properties. Paleoceanography and Paleoclimatology, 33(9): 1013-1034. DOI: 10.1029/2018PA003408

Whitney DossTom Marchitto, Eagle, R., Rashid, H., Tripati, A. 2018: Deconvolving the saturation state and temperature controls on benthic foraminiferal Li/Ca, based on downcore paired B/Ca measurements and coretop compilation. Geochimica et Cosmochimica Acta, 236(SI): 297-314. DOI: 10.1016/j.gca.2018.02.029

All publications by Tom Marchitto >



Current Courses

  • GEOL 3070: Introduction to Oceanography (every Spring)
    Explores Earth's dynamic oceans. The course is roughly divided amongst the four main disciplines of oceanography: marine geology, marine chemistry, physical oceanography (i.e., circulation), and marine biology. Students will learn that there is much overlap and interdependence between these disciplines. Specific topics include seafloor spreading, marine sediments, salinity, biogeochemical cycles, ocean structure, currents, waves, tides, primary production, marine ecology, climate change, and much more.

Past Courses

Postdocs & Students






American Journal of Science
Annual Review of E&PS
Chemical Geology
Climate Dynamics
Climate of the Past
Climatic Change
Deep Sea Research I
Deep Sea Research II
Earth and Planetary Science Letters
Geochimica et Cosmochimica Acta
Geophysical Research Letters
Global Biogeochemical Cycles
The Holocene
Journal of Climate
JGR Atmospheres
JGR Oceans
Journal of Physical Oceanography
Journal of Quaternary Science
Marine Chemistry
Marine Geology
Marine Micropaleontology
Nature Geoscience
Progress in Oceanography
Quaternary Research
Quaternary Science Reviews

Chinook Catalog
Interlibrary Loan
Web of Science