An Ongoing Shift in Pacific Ocean Sea Level

Benjamin Hamlington (Old Dominion University, United States)

CoAuthors

Se-Hyeon Cheon (Seoul National University, Korea); Philip Thompson (University of Hawaii, USA); Mark Merrifield (University of Hawaii, USA); Robert Nerem (University of Colorado, USA); Robert Leben (University of Colorado, USA)

Event: 2016 Ocean Surface Topography Science Team Meeting

Session: Science II: From large-scale oceanography to coastal and shelf processes

Presentation type: Type Oral

Based on the satellite altimeter data, sea level off the west coast of the United States has increased over the past five years, while sea level in the western tropical Pacific has declined. Understanding whether this is a short-term shift or the beginning of a longer-term change in sea level has important implications for coastal planning efforts in the coming decades. Here, we identify and quantify the recent shift in Pacific Ocean sea level, and also seek to describe the variability in a manner consistent with recent descriptions of El Nino-Southern Oscillation (ENSO) and particularly the Pacific Decadal Oscillation (PDO). More specifically, we extract two dominant modes of sea level variability, one related to the biennial oscillation associated with ENSO and the other representative of lower-frequency variability with a strong signal in the northern Pacific. We rely on cyclostationary empirical orthogonal function (CSEOF) analysis along with sea level reconstructions to describe these modes and provide historical context for the recent sea level changes observed in the Pacific. As a result, we find that a shift in sea level has occurred in the Pacific Ocean over the past few years that will likely persist in the coming years, leading to substantially higher sea level off the west coast of the United States and lower sea level in the western tropical Pacific.
 

Oral presentation show times:

RoomStart DateEnd Date
Richelieu Wed, Nov 02 2016,14:15 Wed, Nov 02 2016,14:30
Benjamin Hamlington
Old Dominion University
United States
bhamlington@gmail.com