Johnston Lab Harvard University
Our Lab is committed to fostering an inclusive environment that strives to ensure the success of all team members. Together we tackle hard questions in Earth History, modern climate and biogeochemical cycling, and beyond with a common theme of developing and applying novel stable isotope systematics. We recognize that our lab facilities - and Harvard University - sit on the land of the Massachusett, Wampanoag, and Nipmuc people. Finally, we conduct ourselves following a shared set of expectations to best promote a safe and productive workplace.
a snapshot of our philosophy ...
recent adventures ...
exploration in Earth History:
Minsky, Charlotte, et al. "Repeated snowball–hothouse cycles within the Neoproterozoic Sturtian glaciation." Proceedings of the National Academy of Sciences 123.19 (2026): e2525919123.
Crockford, P.W., Waldeck, A.R., Bekker, A., Kunzmann, M., Ghosh, R., Ghosh, P., Sergeeva, N.D., Michurin, S.V., Halevy, I. and Johnston, D.T., 2025. Depositional Controls on $\Delta^{17}$O Signatures of Sedimentary Sulfate. Geophysical Research Letters, 52(12), p.e2024GL114184.
Waldeck, Anna R.*, et al. "Marine sulphate captures a Paleozoic transition to a modern terrestrial weathering environment." Nature communications 16.1 (2025): 2087.
Exploration in modern climate:
Multiple oxygen isotope constraints on aerobic respiration and Gross Primary Productivity (coming soon)
And beyond:
Oxygen Isotope Evidence that Carbonaceous Chondrites Accreted a Common Organic Component (coming soon)