North American east coast sea level exhibits high power and spatiotemporal complexity on decadal timescales

• Published in: Geophysical Research Letters
• Main Authors: Little, Christopher M., Piecuch, Christopher G., Ponte, Rui M.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: American Geophysical Union 2021
• Subjects: Tide gauge; Decadal; Sea level; Coastal flood; Cape Hatteras; East coast; North Atlantic
• Online Access: https://hdl.handle.net/1912/27738

Author Posting. © American Geophysical Union, 2021. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 48(15), (2021): e2021GL093675, https://doi.org/10.1029/2021GL093675. Tide gauges provide a rich, long-term, record of the amplitude and spatiotemporal structure of interannual to multidecadal coastal sea-level variability, including that related to North American east coast sea level “hotspots.” Here, using wavelet analyses, we find evidence for multidecadal epochs of enhanced decadal (10–15 year period) sea-level variability at almost all long ( 70 years) east coast tide gauge records. Within this frequency band, large-scale spatial covariance is time-dependent; notably, coastal sectors north and south of Cape Hatteras exhibit multidecadal epochs of coherence ( 1960–1990) and incoherence ( 1990-present). Results suggest that previous interpretations of along coast covariance, and its underlying physical drivers, are clouded by time-dependence and frequency-dependence. Although further work is required to clarify the mechanisms driving sea-level variability in this frequency band, we highlight potential associations with the North Atlantic sea surface temperature tripole and Atlantic Multidecadal Variability. Christopher M. Little acknowledges funding support from NSF Grant OCE-1805029. CGP and RMP were funded through NASA Sea Level Change Team (CGP: Grant 80NSSC20K1241). 2022-01-15