Abstract: Reconstructing past climates is critical for understanding the full range of Earth system responses to external forcing. The two tools available to us to undertake this task are climate models, which can be used to simulate ancient climatic conditions, and proxy data, which record climate changes through geochemical, sedimentological, or biological information. Proxy data record what actually happened, but they are not evenly distributed in time nor space and can carry large uncertainties. Models provide a full-field view of past climates, but as simulations, they are only a best guess at what might have happened, and are also subject to bias. Paleoclimate data assimilation provides a solution, as it combines these two pieces of information in order to leverage both model and proxy information. In this talk, I will review the paleoclimate data assimilation projects that our group has undertaken in the past few years and what we have learned about past and future climate change as a result.
The Earth Science Colloquium Series, sponsored by Lamont-Doherty Earth Observatory and Columbia University Department of Earth and Environmental Sciences (DEES), provides a lively forum for discussing a wide variety of topics within the Earth sciences and related fields. Colloquia are attended by the full range of scientific and technical staff at LDEO. Colloquium attendance is required of all pre-orals DEES graduate students. The Colloquium Series supports the Lamont Seminar Diversity Initiative.