Grant: Discovery Grants Program - Individual

The past offers a powerful window for understanding future climate change. Evidence from the past, for instance, suggests that ice and melt-water discharge has played a critical role in abrupt climate change. In this general context, the research will target three fundamental objectives. First, to reconstruct and subsequently refine well-constrained deglacial (and eventually full glacial cycle) ice-sheet and melt-water chronologies with well-defined error bars. Second, extending this, to elucidate the role of melt-water fluxes in climate change during the last glacial cycle. Finally, probability distributions for the future evolution of the present-day ice-sheets will be determined and over time refined. The approach taken involves a sequence of statistically rigorous calibrations of a 3-dimensional glacial and climate system model against large and diverse sets of paleo data (including relative sea-level data, geodetic observations, and pro-glacial lake levels). After construction of an interim calibrated global deglacial ice and melt-water chronology, the dynamical role of melt-water fluxes will be analyzed through coupled ocean-atmospheric-vegetation and glacial system modelling. Running the calibrated fully coupled model into the future will provide probability distributions for the future evolution of the present-day ice-sheets. This will address a major gap in current climate change assessments. The novelty of this work lies in the application of a comprehensive earth systems modelling approach that is highly data-integrated and probabilistic to major questions concerning polar climate stability and the role of melt-water in abrupt climate change. More generally, the work will be a case study in improving methodologies for rigorously analyzing the dynamics of complex nonlinear physical systems in an observation-grounded manner.