Dr Matt Osman

Assistant Professor of Climate Science

Biography

Career

• 2023-: Assistant Professor, Dept. of Geography, University of Cambridge
• 2023-: Affiliated Researcher, Dept. of Geosciences, University of Arizona
• 2019-2022: Postdoctoral Research Associate, Dept. of Geosciences, University of Arizona

Qualifications

• Ph.D. in Climate Sciences, Massachusetts Institute of Technology and Woods Hole Oceanographic Institution (MIT/WHOI)
• B.A. in Geosciences, Augustana College, Illinois

Selected awards

• Marie Skłodowska-Curie Actions Fellowship (European Commission; declined offer)
• Ocean Outlook Fellowship, Bjerknes Centre for Climate Research, Norway
• National Defense Science and Engineering Graduate Fellowship (US-DoD)
• Fulbright Research Fellowship (University of Stockholm; declined offer)

Research

My research seeks to uncover the mechanisms of climate variability across seasonal to millennial time scales and across regional to global spatial scales. My work combines large and diverse climate “proxy” databases (in particular, ice cores and ocean sediments), state-of-the-art global climate simulations, physicochemical proxy models, and modern observations to understand past and present climate change in statistically sound, mechanistically grounded ways. By studying the past and present, my research aspires toward a more equitable and sustainable future for Earth, its inhabitants, and its ecosystems.

At present, my research program is fit around the following three themes:

• Past global change via paleoclimate data assimilation: By explicitly pairing together proxies with global climate model simulations, paleoclimate data assimilation approaches are helping us disentangle the nature and magnitude of past climate changes within a dynamically consistent, spatially complete, and observationally constrained framework. Ongoing periods of research interest include the Mid-Pliocene Warm Period (3.2 Ma before present), the Last Interglacial (~127 ka BP), the Last Glacial Maximum (21 ka BP) and the Holocene (last ~11 ka BP).
• Polar change through climate-proxy development: The high latitudes are currently home to some of the most dramatic human-induced changes on Earth. As polar changes have global impacts, better pre-observational insights are needed. Glacial ice and marine sediments situated at high latitudes each provide lucrative mediums for uncovering past polar changes, albeit with still-untapped potential. Ongoing interests are in pairing novel statistical techniques with these proxies to constrain past sea ice; marine productivity; glacial; and atmospheric dynamics during recent centuries to millennia.
• Cryosphere—climate coupling across timescales:  Models predict a net decline in the global cryosphere (i.e., ice sheet and glacier extent, sea ice, and seasonal snow cover) during the coming centuries, irrespective of greenhouse gas emissions scenario followed. These changes will undoubtedly contribute to continued global sea level and surface temperature rise, but the rate, magnitude, and ramifications of these changes remain highly uncertain. Ongoing interests are in combining models and proxies to better-constrain sea ice and ice sheet decay processes across past warm and cold intervals, and in developing new coastal ice cores to understand coastal ice cap change in Greenland.

Recently funded projects

A paleoclimate reanalysis of the coupled Greenland Ice Sheet–climate evolution during the Last Interglacial (US NSF-funded; 2022-2025)

Research opportunities

I openly encourage inquiries from prospective PhD students and MPhil students interested in quantitative, multi-disciplinary, and curiosity-driven climate research.  Please also check out the following Ph.D. research opportunities currently listed through the NERC Doctoral Training Programme:

1. CE529: Reconstructing Greenland Ice Sheet decay and global sea level rise during the Last Interglacial warm period
2. CE530: Mining the “big data” of Earth’s geologic past through physics-based statistical learning
3. CE524: Reconstructing the geometry of AMOC across multiple timescales
4. CE536: Using proxy biases to assess seasonality and inter-annual impacts of past abrupt climate change
5. CE535: An ice-free Arctic: why was Arctic warmth amplified during past Interglacials?

We are currently advertising the following Postdoctoral Research Associate position (24 months funded) in paleoclimate data assimilation to reconstruct the global carbon cycle spanning the past 50 thousand years.

Publications

Selected recent work

• Osman, M.B., J.E. Tierney, J. Zhu, R. Tardif, J. King, G.J. Hakim and C.J. Poulsen: Globally resolved surface temperatures since the Last Glacial Maximum, Nature, 599, 239-244, 2021. https://doi.org/10.1038/s41586-021-03984-4
• Osman, M.B., S. Coats, J.R. McConnell, N. Chellman, S.B. Das: North Atlantic jet stream projections from a 1,250 year context, Proceedings of the National Academy of Sciences, 118(38), e2104105118, 2021. https://doi.org/10.1073/pnas.2104105118
• Osman, M.B., B.E. Smith, L.D. Trusel, S.B. Das, J.R. McConnell, N. Chellman, M. Arienzo, and H. Sodemann: Abrupt Common Era hydroclimate shifts drive west Greenland ice cap change, Nature Geoscience, 14, 756–761, 2021. https://doi.org/10.1038/s41561-021-00818-w
• Osman, M.B., Das, S.B., Trusel, L.D., Evans, M., Fischer, H., Grieman, M., Kipfstuhl, S., McConnell, J.R., Saltzman, E.: Industrial-era decline of subarctic Atlantic productivity, Nature, 569, 551-555, 2019. https://doi.org/10.1038/s41586-019-1181-8
• Trusel, L.D., Das, S.B., Osman, M. B., et al.: Nonlinear rise in Greenland runoff in response to post-industrial Arctic Warming, Nature, 564, 104–108, 2018. https://doi.org/10.1038/s41586-018-0752-4
• Osman, M.B., Das, S.B., Marchal, O., and Evans, M.J.: Methanesulfonic acid (MSA) migration in polar ice: Data synthesis and theory, The Cryosphere, 11, 2439-2462, 2017. https://doi.org/10.5194/tc-11-2439-2017

Teaching

• Geographical Tripos Part 1a, Paper 2
• Geographical Tripos Part 1b, Paper 5
• Geographical Tripos Part 2, Paper 11
• MPhil in Holocene Climates