About

I'm a postdoctoral researcher at the University of Utah. I study paleoclimatology and paleoceanography, focusing on the coupling of climate and the carbon cycle over long and short timescales in the geologic past. I use trace element and stable isotope geochemical proxies in marine (e.g., fossil foraminifera) and terrestrial (e.g., paleosol carbonates) sediments, to determine temperature, carbon dioxide in the atmosphere, and seawater chemistry (e.g., ocean acidification, shifts in sea surface salinity) in the past.

I develop Bayesian hierarchical models to translate between proxy data and past environmental conditions. In part, I work on abrupt climate events associated with shifts in atmospheric carbon concentrations (i.e., carbon isotope excursions, including early Eocene hyperthermals and Cretaceous OAEs), as carbon release case studies to better understand the sensitivity of climate and carbon cycle feedbacks to changes in atmospheric carbon dioxide.

I'm a contributor to the CO2 Proxy Integration Project (CO2PIP) - find out more here

I'm a member of the SPATIAL (Spatio-Temporal Isotopes Analytics Lab) group at the University of Utah - find out more here

Besides research, I enjoy cooking, mountain biking and hiking with my dogs.

Research

Siem Driller visits the core laboratory to view the split section halves he drilled that day. Dustin Harper (Sedimentologist, University of Kansas, USA) explains their features and geological background. (Credit: Sandra Herrmann, IODP JRSO) [Photo ID: exp396_131]

I'm a paleoclimatologist and paleoceanographer with a focus on genearting stable isotope proxy records across warm intervals in Earth's past and developing Bayesian approaches used to interpret those records.

Sample of questions that motivate my research:

-How much did temperature, sea surface pH, and CO2 change during global warming events of the early Eocene (hyperthermals)?

-What was the spatial response of temperature and sea surface salinity change during hyperthermal events, and how does the latter relate to heat-driven shifts in the hydrological cycle?

-How are temperature and atmospheric CO2 coupled over long (Myrs) and short (kyrs) timescales?

-How senstive was the climate to CO2 released into the atmosphere during the past, and how does this change across timescales?

-Were cool intervals during the Aptian-Albian driven by low atmospheric CO2?

-How has atmospheric CO2 changed over the past 66 Myr? 541 Myr?

-Can we develop a community-accessible Bayesian proxy system model that incorporates commonly applied measurements in fossil planktic foraminifera (stable boron, carbon and oxygen isotopes, B/Ca, Mg/Ca) to interpret the past environment, including atmospheric CO2?

-What other proxy systems can we forward model using Markhov Chain Monte Carlo (MCMC) approaches?

Field Expeditions

Freshly split core material with scientists making observations

This research relies on scientific ocean drilling and continental field work to obtain fossils of marine organisms, leaves and soils suitable for reconstructing the past environments in which they were deposited. The International Ocean Discovery Program (IODP) has provided the majority of my sample material, and I have sailed on two IODP expeditions as a science party member.

IODP Expedition 371

IODP Expedition 396

I have also worked on terrestrial depositional localities in central Utah, USA. I enjoy getting a first hand look at core material as it comes on board and collecting terrestrial samples in situ so I can better understand the history of deposition and alteration.

Analytical Chemistry

Foraminifera picking stations in Cambridge, UK, Godwin Lab

After samples are collected, material must be prepared for analysis. For foraminifera-based work this requires physically picking out individual microscopic shells, and chemically cleaning them. For paleosols, nodules must be cut and thin sections are often made so that primary carbonate can be identified and sampled.

Once appropriate materials are isolated and cleaned they are geochemically analyzed using a combination of Isotope Ratio Mass Spectrometry (IRMS), Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and/or Thermal Ionization Mass Spectrometry (TIMS).

Bayesian Proxy System Models

Foraminifera forward proxy system model

Most paleoclimatologists use geochemical data to interpret the past envrironment with some sort of Proxy System Model (PSM). My work has focused on improving these models by developing PSMs that work in a forward direction (i.e., from environment to geochemical measurement, as opposed to the traditional inverse methods).

These models are placed in a Bayesian framework in which Markhov Chain Monte Carlo (MCMC) methods are used to generate posterior distributions of environmental variables conditioned on proxy measurements. Part of this work includes making community-accessible tools so that these PSMs can be widely used as they continue to be developed.

Check out the GitHub page that houses the Bayesian Paleo-Environment Reconstructor (or BPER) and includes tutorial-like vignettes that walk users through the available functions in the package.

Media

My research has been featured in several popular media outlets. Here are some links!

News Articles

  • U. researcher leads study into what microscopic fossilized shells say about climate change, KSL Link
  • What microscopic fossilized shells tell us about ancient climate change, UNews Link
  • Birth of North Atlantic Ocean 55M years ago caused rapid global warming, The Guardian Link
  • Ancient volcanism drove ancient global warming that marked the end of the Paleocene, UNews Link
  • ‘Lost continent’ expedition provides clues to Earth’s history, National Geographic Link
  • Scientific expedition reveals secrets of lost continent of Zealandia, New Zealand Herald Link
  • Zealandia drilling reveals secrets of sunken lost continent, The Guardian Link
  • Zealandia: Scientists set to drill into long-lost continent to uncover its secrets, Newsweek Link
  • Scientists embark on expedition to submerged continent Zealandia, NSF News Release Link

Video

  • Education and Outreach YouTube video - I give a guided tour of the science facilities aboard the JOIDES Resolution. This is from a live feed during an education and outreach stream event. Apologies in advance for the rough sound and video! Link

Contact

email: dustin.t.harper@utah.edu

University of Utah
Dept. of Geology and Geophysics
115 S 1460 E
Salt Lake City, UT 84112-0102

Check out my GitHub here

My Google Scholar account is here

Articles

23. Dustin Harper, A. Lam, D. Penman, J. Frieling, N. Varela, S. Chatterjee. The Value of Scientific Ocean Drilling for Early Career Researchers. Correspondence accepted for publication in Nature Geoscience.

22. Carlos Alvarez Zarikian, S. Yager, M. Christopoulou, N. Varela, V. Clementi, and D. Harper, 2024. Data Report: X-ray fluorescence scanning of Site U1574, Vøring Plateau, IODP Expedition 396. https://doi:10.14379/iodp.proc.396.201.2024 Proceedings of the International Ocean Discovery Program.

Alvarez Zarikian et al. (2024) IODP Proceedings

21. Bärbel Hönisch, C. Witkowski, D. Penman, D. Harper, M. Henehan, P. Polissar, 2024. Paleo-atmospheric CO2 reconstructions from deep-ocean sediments. https://doi.org/10.22498/pages.32.2.84. PAGES magazine.

Hönisch et al. (2024) PAGES Magazine

20. Dustin Harper, B. Hönisch, G. Bowen, R. Zeebe, L. Haynes, D. Penman, and J. Zachos, 2024. Long- and short-term coupling of sea surface temperature and atmospheric CO2 during the late Paleocene and early Eocene. https://doi.org/10.1073/pnas.2318779121. Proceedings of the National Academy of Science.

Harper et al. (2024) PNAS

19. Ashley Morris, S. Lambart, M. Stearns, J. Bowman, M. Jones, G. Mohn, G. Andrews, J. Millet, C. Tegner, S. Chatterjee, J. Frieling, P. Guo, D. Jolley, E. Cunningham, C. Berndt, S. Planke, C. Alvarez Zarikian, P. Betlem, H. Brinkhuis, M. Christopoulou, E. Ferrè, I. Filina, D. Harper, J. Longman, R. Scherer, N. Varela, W. Xu, S. Yager, A. Agarwal, and V. Clementi, 2024. Evidence for Low-Pressure Crustal Anatexis During the Northeast Atlantic Break-up. https://doi.org/10.1029/ 2023GC011413. Geochemistry, Geophysics, Geosystems.

Morris et al. (2024) G cubed

18. Madeleine Vickers, M. Jones, J. Longman, C. Ullman, M. Vickers, J. Frieling, D. Harper, V. Clementi, S. Planke, and the IODP Expedition 396 Science Party, 2024. Paleocene-Eocene age glendonites from the Norwegian Margin – Indicators of cold snaps in the hothouse? https://doi.org/10.5194/cp-20-1-2024. Climate of the Past.

Vickers et al. (2024) Climate of the Past

17. CenCO2PIP Consortium, 2023. Towards a Cenozoic history of atmospheric CO2, https://doi.org/10.1126/science.adi5177. Science.

CenCO2PIP Consortium (2023) Science

16. Christian Berndt, S. Planke, C.A. Zarikian, J. Frieling, J. Millett, M. Jones, H. Brinkhuis, S. Bünz, H. Svensen, J. Longman, R. Scherer, J. Karstens, B. Manton, R. Huismans, J. Faleide, A. Agarwal, G. Andrews, P. Betlem, J. Bhattacharya, S. Chatterjee, M. Christopoulou, V. Clementi, E. Ferré, I. Filina, P. Guo, D. Harper, S. Lambart, G. Mohn, R. Nakaoka, C. Tegner, N. Varela, M. Wang, W. Xu, and S. Yager, 2023. Shallow-marine hydrothermal venting linked to Paleocene Eocene Thermal Maximum, https://doi.org/10.1038/s41561-023-01246-8. Nature Geoscience.

Berndt et al. (2023) Nature Geoscience

15. Joji Uchikawa, D. Penman, D. Harper, J. Farmer, J. Zachos, N. Planavsky, and R. Zeebe, 2023. Sulfate and phosphate oxyanions alter B/Ca and δ11B in inorganic calcite at constant pH: Crystallographic controls over normal kinetic effects, https://doi.org/10.1016/j.gca.2022.12.018. Geochimica et Cosmochimica Acta.

Uchikawa et al. (2023) GCA

14. Wanda Stratford, R. Sutherland, G. Dickens, P. Blum, J. Collot, M. Gurnis, S. Saito, C. Agnini, L. Alegret, G. Asatryan, A. Bordenave, J. Bhattacharya, L. Change, M. Cramwinckel, E. Dallanave, M. Drake, S. Etienne, M. Giorgioni, D. Harper, H. Huang, A. Keller, A. Lam, H. Li, H. Matsui, H. Morgans, C. Newsam, Y. Park, K. Pascher, S. Pekar, D. Penman, T. Westerhold, and X. Zhou, 2022. Timing of Eocene compressional plate failure during subduction initiation, northern Zealandia, southwestern Pacific, https://doi.org/10.1093/gji/ggac016. Geophysical Journal International.

Stratford et al. (2022) GJI

13. Rupert Sutherland, Z. Dos Santos, C. Agnini, L. Alegret, A. Lam, T. Westerhold, M. Drake, D. Harper, E. Dallanave, C. Newsam, M. Cramwinckel, G. Dickens, J. Collot, S. Etienne, A. Bordenave, W. Stratford, X. Zhou, H. Li, G. Asatryan, 2022. Neogene mass accumulation rate of carbonate sediment in the Tasman Sea, southwest Pacific, https://doi.org/10.1029/2021PA004294. Paleoceanography and Paleoclimatology.

Sutherland et al. (2022) Paleo & Paleo

12. Dustin Harper, M. Suarez, J. Uglesich, H. You, D. Li, P. Dodson, 2021. Aptian-Albian clumped isotopes from northwest China: Cool temperatures, variable atmospheric pCO2 and regional shifts in the hydrologic cycle, https://doi.org/10.5194/cp-2020-152. Climate of the Past.

Harper et al. (2021) Climate of the Past

11. Laia Alegret, D. Harper, C. Agnini, C. Newsam, T. Westerhold, M. Cramwinckel, E. Dallanave, G. Dickens, R. Sutherland, 2021. Biotic Response to Early Eocene Warming Events: Integrated Record from Offshore Zealandia, North Tasman Sea, https://doi.org/10.1029/2020PA004179. Paleoceanography and Paleoclimatology.

Alegret et al. (2021) Paleo & Paleo

10. Gabriella Kitch, A. Jacobson, D. Harper, M. Hurtgen, B. Sageman, J. Zachos, 2021. Calcium isotope composition of Morozovella velascoensis over the late Paleocene-early Eocene, https://doi.org/10.1029/2020PA003932. Geology.

Kitch et al. (2021) Geology

9. Marlow Cramwinckel, H. Coxall, K. Śliwińska, M. Polling, D. Harper, P. Bijl, H. Brinkhuis, J. Eldrett, A. Houben, F. Peterse, S. Schouten, G.J. Reichart, J. Zachos, A. Sluijs, 2020. A warm, stratified, and restricted Labrador Sea across the middle Eocene and its Climatic Optimum, https://doi.org/10.1029/2020PA003932. Paleoceanography and Paleoclimatology.

Cramwinckel et al. (2020) Paleo & Paleo

8. Timothy Bralower, J. Cosmidis, P. Heaney, L. Kump, J. Morgan, D. Harper, S. Lyons, K. Freeman, K. Grice, J. Wendler, J. Zachos, N. Artimieva, S. Chen, S. Gulick, C. House, H. Jones, C. Lowery, C. Nims, B. Schaefer, E. Thomas, V. Vajda, 2020. Global microbial blooms during the immediate aftermath of the Cretaceous–Paleogene boundary impact, https://doi.org/10.1016/j.epsl.2020.116476. Earth Planet. Sci Lett.

Bralower et al. (2020) EPSL

7. James Barnet, D. Harper, L. LeVay, K. Edgar, M. Henehan, T. Babila, C. Ullmann, M. Leng, D. Kroon, J. Zachos, K. Littler, 2020. Coupled evolution of temperature and carbonate chemistry during the Paleocene–Eocene; new trace element records from the low latitude Indian Ocean, https://doi.org/10.1016/j.epsl.2020.116414. Earth Planet. Sci Lett.

Barnet et al. (2020) EPSL

6. Rupert Sutherland, G. Dickens, P. Blum, C. Agnini, L. Alegret, J. Bhattacharya, A. Bordenave, L Chang, J, Collot, M. Cramwinckel, E. Dallanave, M. Drake, S. Etienne, G. Martino, M. Gurnis, D. Harper, H. Huang, A. Keller, A. Lam, H. Li, H. Matsui, C. Newsam, Y. Park, K. Pascher, S. Pekar, D. Penman, S. Satio, W. Stratford, T. Westerhold, X. Zhou, 2020. Continental scale of geographic change across Zealandia during subduction zone initiation, https://doi.org/10.1130/G47008.1. Geology.

Sutherland et al. (2020) Geology

5. Dustin Harper, B. Hönisch, R. Zeebe, G. Shaffer, L. Haynes, E. Thomas, J. Zachos, 2020. The magnitude of surface ocean acidification and carbon release during Eocene Thermal Maximum 2 (ETM-2) and the Paleocene–Eocene Thermal Maximum (PETM), https://doi.org/10.1029/2019PA003699. Paleoceanography and Paleoclimatology.

Harper et al. (2020) Paleo & Paleo

4. Rupert Sutherland, G. Dickens, P. Blum, C. Agnini, L. Alegret, J. Bhattacharya, A. Bordenave, L. Chang, J. Collot, M. Cramwinckel, E. Dallanave, M. Drake, S. Etienne, G. Martino, M. Gurnis, D. Harper, H. Huang, A. Keller, A. Lam, H. Li, H. Matsui, C. Newsam, Y. Park, K. Pascher, S. Pekar, D. Penman, S. Saito, W. Stratford, T. Westerhold, X. Zhou, 2018. International Ocean Discovery Program Expedition 371 Preliminary Report: Tasman frontier subduction initiation and Paleogene climate, https://doi.org/10.14379/iodp.pr.371.2018. Integrated Ocean Drilling Program: Preliminary Reports.

Sutherland et al. (2018) IODP Prelim Reports

3. Maximillian Vahlenkamp, I. Niezgodzki, D. De Vleeschouwer, T. Bickert, D. Harper, S.K. Turner, G. Lohmann, P. Sexton, J. Zachos, H. Pälike, 2018. Astronomically paced changes in deep-water circulation in the Western North Atlantic during the Middle Eocene, https://doi.org/10.1016/j.epsl.2017.12.016. Earth Planet. Sci Lett.

Vahlenkamp et al. (2018) EPSL

2. Dustin Harper, R. Zeebe, B. Hönisch, C.D. Schrader, L.J. Lourens, J. Zachos, 2018. Subtropical sea surface warming and increased salinity during Eocene Thermal Maximum 2, https://doi.org/10.1130/G39658.1. Geology.

Harper et al. (2018) Geology

1. Joji Uchikawa, D. Harper, D. Penman, J. Zachos, R. Zeebe, 2017. Influence of solution chemistry on the boron content in inorganic calcite grown in artificial seawater, https://doi.org/10.1016/j.gca.2017.09.016. Geochimica et Cosmochimica Acta.

Uchikawa et al. (2017) GCA