I am interested in marine ecosystem dynamics and physical-biological interactions over a broad range of space and time scales. Since joining the climate and ecosystems group at GFDL, my work has focused on two general areas of research. The first is the response of marine ecosystems (and the living marine resources within them) to climate change and variability. The second is the development of more comprehensive and mechanistic marine ecosystem models for GFDL's Earth System Models.
A multitude of studies have identified strong responses of LMRs to climate variability and evidence for responses to anthropogenic climate change is accumulating. For LMR management strategies to be more effective in a variable and changing climate, they must directly consider climate-ecosystem interactions. Predicting the impacts of future climate on LMRs requires both an understanding of the mechanisms through which climate acts on ecosystems and skillful predictions of climate change and variability at relevant space and time-scales. I have been working with colleagues at GFDL, collaborators throughout NOAA, scientists from Princeton and the Cooperative Institute for Climate Sciences, and a range of academic and research institutions to develop innovative applications of climate and earth system models to LMR assessments. One of the first products from these efforts is a review and sythesis paper: "On the Use of IPCC-class models to assess the impact of climate on living marine resources". This paper assesses the utility of present climate and LMR models for assessing the impact of climate on LMRs, lists recommended practices for such applications, and identifies priority developments. Brief descriptions of ongoing projects will be added to this page as they are completed.
Earth System Models combine the traditional components of physical climate models (land, ocean, atmosphere and ice models) with models for land vegetation and marine ecosystem dynamics to allow direct simulation of the global carbon cycle. ESMs allow exploration of important feedbacks between ecosystems and the physical climate system. Marine ecosystem models developed for ESMs generally emphasize resolution of large-scale nutrient and carbon cycles most strongly linked to these feedbacks. These models have also proven useful in assessing the potential impacts of phenomena such as climate-driven changes in primary production, nutrient distribution and transport, and ocean acidification on LMRs. The treatment of planktonic food web dynamics in marine ecosystems models developed for ESMs, however, is often highly simplified. Uncertainties surrounding the impact of climate change on the processes controlling the flow of energy from phytoplankton to fish limit confidence in projections of future fisheries production. I am working to develop global-scale marine ecosystem models that:
1. Capture interactions between the ocean's global carbon and nutrient cycles and climate with a more highly-resolved and mechanistic representation of planktonic ecosystem dynamics.
2. Capture the impact of climate on broad-scale patterns in the flow of energy through the planktonic foodweb to fisheries and other living marine resources.
This model, which we have called COBALT (Carbon, Ocean Biogeochemistry and Lower Trophics) is presently under development. My primary collaborators on the initial version of this model are John Dunne and Jasmin John. However, the model is intended to provide a baseline for continued development which we are pursuing through collaborations with a range of other investigators. Updates will be posted periodically on this website.
GFDL, room 302b
Princeton University Forrestal Campus
201 Forrestal Road
Princeton, NJ 08540-6649