Physics of Oceans and Paleoclimates

Projects

Connecting ocean tracers to global climate

We are using the MITgcm adjoint to infer atmospheric changes (like wind stress amplitudes, in red) that change abyssal watermass distributions in ways suggested by paleo data.

Inferring the glacial ocean state from models + data

Fitting numerical models to observations paints a physically consistent picture of the ocean 20,000 years ago.

Reconstructing Atlantic Ocean heat content over the last 1000 years

I am extending the Last Millennium Reanalysis to include ocean observations and determine what we can – and can’t – say about internal climate variability over the last 1000 years.

Signal and noise in paleoclimate records

Using proxy data is like playing a game of ‘telephone’ with past climate – sometimes the information gets garbled. I am working to quantify errors arising from proxy sampling procedures.

Tools for accelerating tracer simulations

Simulating ocean tracers is computationally expensive. New online extrapolation and preconditioning techniques allow us to estimate equilibria in a fraction of the time.

Publications submitted and in preparation

(subm). A Review of the Role of AMOC Variability in Atlantic Multidecadal Variability and Associated Climate Impacts. Subm. to Reviews in Geophysics.

(in prep.). Dynamical controls on the depth of the boundary between bottom and deep waters in the Last Glacial Maximum Atlantic. In prep. for JGR Oceans.

(in prep.). Quantifying Proxy Influence in the Last Millennium Reanalysis. In prep. for Climate of the Past.

(subm.). Quantifying uncertainties due to discontinuous sampling of paleoclimate records. Paleoceanography and Paleoclimate, in revision.

Publications

(2018). A global glacial ocean state estimate constrained by upper-ocean temperature proxies. Journal of Climate.

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(2018). A synthesis of deglacial deep-sea radiocarbon records and a test of their (in)consistency with modern ocean circulation. Paleoceanography and Paleoclimatology.

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(2013). Direct Observations of Forma- tion and Propagation of Subpolar Eddies into the Subtropical North Atlantic. Deep Sea Research Part II: Topical Studies in Oceanography.

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