Sea Level Variability along the United States East Coast...and beyond!

Special CIRES/ATOC Seminar
Dr. Chris Little, Atmospheric and Environmental Research, Lexington, MA
CIRES Visiting Fellows Program (Sabbatical)
Sea Level Variability along the United States East Coast...and beyond!
Coastal sea level records from tide gauges provide a unique and valuable resource for understanding decadal to centennial timescale climate variability. The tide gauge record along the United States east coast (USEC) is of particular interest, because of its length and relatively dense spatial coverage. Among other signals, USEC sea level exhibits large amplitude (up to 10 cm), decadal-timescale, variations arising from changes in ocean circulation. Lagged relationships with atmospheric and ocean variability suggest these changes in coastal sea level may be predictable and/or used to infer past changes in ocean circulation and climate. In fact, the USEC tide gauge record has already been used to reconstruct large-scale North Atlantic ocean variability. However, caution is warranted: several recent analyses reveal non-stationarity and linkages to climate and sea level variability in other ocean basins. Robust reconstructions of climate, and predictions of coastal sea level, require an improved mechanistic understanding.
Understanding the dynamics underlying decadal USEC sea level variations, and its apparent modulation over multidecadal timescales, requires global models with adequate representation of key processes, including those that govern the communication of large-scale climate variability to the coast. During my CIRES sabbatical, I’ve begun to assess theoretical and modelling tools that will help address some of outstanding questions in the coastal sea level record. In this talk, I will present some elements of the spatiotemporal variability evident in the USEC and global tide gauge record, review relevant driving mechanisms and potential relationships with other decadal climate phenomena, introduce initial findings from high resolution ocean models, and outline some promising research directions. My hope is to inspire new ideas and collaborations around ATOC and CIRES…and beyond.