The impacts of ENSO/PDO on regional sea level change: After 20 years, are we finally seeing a change in the pattern of Pacific sea level change?
Event: 2015 Ocean Surface Topography Science Team Meeting
Session: Science III: Large scale and global change ocean processes: the ocean's role in climate
Presentation type: Type Oral
Over the first 20 years of the TOPEX/Jason-1/Jason-2 missions, sea level in the western Pacific has been steadily going up at a rate of ~10 mm/year while sea level in the eastern Pacific has been modestly declining. Merrifield (2010) used long time series of tide gauge data in the western Pacific to show that the altimeter record occurs at a rather unique period in the history of sea level, likely related to the phase of the Pacifiic Decadal Oscillation (PDO). However, since roughly late 2013, this pattern may be beginning to reverse, as regional sea level has been falling in the western Pacific and rising in the eastern Pacific. If this is truly a change from the "cool phase" to the "warm phase" of PDO, then we can expect sea level rise along the coast of California to dramatically increase over the next decade with rates well above the 3 mm/year global average as it recovers from its PDO-induced sea level "deficit". Coupled with the shorter-term ENSO response, this could lead to record high sea level along the western coast of the U.S. Global mean sea level is also likely to hit a new record in the next year in response to ENSO variability. We will review the observational sea level record from altimetry and tide gauges in these contexts and offer some insight into how Pacific regional sea level change might be expected to unfold over the coming years.