Presentation Title

Perspectives on incorporating vertical land movement into local sea level rise projections in the Pacific Northwest

Session Title

Session S-04H: Technical Tools to Support Sea Level Rise Adaptation in the Salish Sea

Conference Track

Shorelines

Conference Name

Salish Sea Ecosystem Conference (2014 : Seattle, Wash.)

Contributing Repository

Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.

Presenter/Author Information

Ian Miller, Washington Sea Grant ProgramFollow

Start Date

1-5-2014 5:00 PM

End Date

1-5-2014 6:30 PM

Abstract

Relative sea level at a particular location is determined by the interplay between mean sea level and the level of the land, both measured against some arbitrary fixed datum. In the Pacific Northwest, complex patterns of vertical land movement associated with inter-seismic strain and isostatic rebound can lead to measurable variations in rates of relative sea level over very short distances along the shoreline. Increasingly, it is becoming clear that developing meaningful sea level rise projections at the community scale in the Pacific Northwest requires understanding and assessing a variety of sources of information on vertical land movement. As part of a comprehensive assessment of community vulnerability to climate change by the Jamestown S’Klallam Tribe (JSKT) in Washington State a set of locally specific sea level vulnerability maps were developed. The maps combined regional projections of mean sea level rise with local estimates of vertical land movement derived from measurements made by the Pacific Northwest Geodetic Array (PANGA). For the Jamestown S’Klallam Tribe’s areas of interest the estimated rate of vertical land movement was approximately -2 mm/yr, and added 0.2 m of sea level rise to the 100 year projections. The approach used during the JSKT assessment relies on a set of assumptions, including: 1) vertical land movement estimated from logging GPS networks is linear and non-varying and 2) the GPS station density is adequate to characterize patterns of vertical land movement across the area of interest. Some of these assumptions are almost certainly invalid and therefore compromise our ability to plan for sea level rise at the local level, even with relatively robust estimates of eustatic sea level rise with quantifiable confidence levels. Better information on rates and patterns of vertical land movement would benefit the climate research and adaptation community as it works to support community efforts to increase climate resilience.

Rights

This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.

Language

English

Format

application/pdf

Type

Text

This document is currently not available here.

Share

COinS
 
May 1st, 5:00 PM May 1st, 6:30 PM

Perspectives on incorporating vertical land movement into local sea level rise projections in the Pacific Northwest

Room 6C

Relative sea level at a particular location is determined by the interplay between mean sea level and the level of the land, both measured against some arbitrary fixed datum. In the Pacific Northwest, complex patterns of vertical land movement associated with inter-seismic strain and isostatic rebound can lead to measurable variations in rates of relative sea level over very short distances along the shoreline. Increasingly, it is becoming clear that developing meaningful sea level rise projections at the community scale in the Pacific Northwest requires understanding and assessing a variety of sources of information on vertical land movement. As part of a comprehensive assessment of community vulnerability to climate change by the Jamestown S’Klallam Tribe (JSKT) in Washington State a set of locally specific sea level vulnerability maps were developed. The maps combined regional projections of mean sea level rise with local estimates of vertical land movement derived from measurements made by the Pacific Northwest Geodetic Array (PANGA). For the Jamestown S’Klallam Tribe’s areas of interest the estimated rate of vertical land movement was approximately -2 mm/yr, and added 0.2 m of sea level rise to the 100 year projections. The approach used during the JSKT assessment relies on a set of assumptions, including: 1) vertical land movement estimated from logging GPS networks is linear and non-varying and 2) the GPS station density is adequate to characterize patterns of vertical land movement across the area of interest. Some of these assumptions are almost certainly invalid and therefore compromise our ability to plan for sea level rise at the local level, even with relatively robust estimates of eustatic sea level rise with quantifiable confidence levels. Better information on rates and patterns of vertical land movement would benefit the climate research and adaptation community as it works to support community efforts to increase climate resilience.