I am a Professor at the University of Texas at Austin in the Department of Geological Sciences (DGS) and joint appointments in the Jackson School of Geosciences (JSG) and the Institute for Geophysics (UTIG). I am a member of the core faculty in the Oden Institute for Computational Engineering and Sciences and hold the W. A. “Tex” Moncrief, Jr., endowed chair III in Simulation-Based Engineering and Sciences. At the Oden Institute, I direct the Computational Research in Ice and Ocean Systems (CRIOS) group.Previously, I have worked for 16 years in the physical oceanography group in the Massachusetts Institute of Technology (MIT) Department of Earth, Atmospheric and Planetary Sciences (EAPS), initially as Postdoc with Prof. Carl Wunsch and most recently as Senior Research Scientist and Visiting Associate Professor. I earned my Ph.D. in 1998 from the Max-Planck-Institute for Meteorology and the University of Hamburg, Germany, working with Prof. Klaus Hasselmann on global ocean surface wave remote sensing and modeling.My main research interest is understanding the general circulation of the ocean and its role in the global climate system. As part of the “Estimating the Circulation and Climate of the Ocean” (ECCO) consortium, we are applying inverse methods for the purpose of fitting a general circulation model with much of the available satellite and in-situ observations to produce an optimal estimate of the time-evolving state over the past few decades of the global ocean and sea ice. ECCO products support ocean circulation and climate variability research on time scales of days to decades. Emerging research foci are understanding the dynamics of sea level change, the provision of formal uncertainties along with these estimates and implications for improving the global ocean observing system for climate.I have also become interested in the cryosphere. My group is improving simulations of coupled sea ice-ocean dynamics in the Arctic and the Southern Ocean. Furthermore, we are investigating the polar ice sheets, their dynamics, their interaction with the ocean, and their contributions to sea level change.