Assessing local impacts of the 1700 CE Cascadia earthquake and tsunami using tree-ring growth histories: a case study in South Beach, Oregon, USA

Details

• Journal Title:
  Natural Hazards and Earth System Sciences
• Personal Author:
  Dziak, Robert P. ; Black, Bryan A. ; Wei, Yong ; Merle, Susan G.
• NOAA Program & Office:
  OAR (Oceanic and Atmospheric Research) ; PMEL (Pacific Marine Environmental Laboratory) ; CIMRS (Cooperative Institute for Marine Resources Studies)
• Description:
  We present an investigation of the disturbance history of an old-growth Douglas-fir (Pseudotsuga menziesii) stand in South Beach, Oregon, for possible growth changes due to tsunami inundation caused by the 1700 CE Cascadia Subduction Zone (CSZ) earthquake. A high-resolution model of the 1700 tsunami run-up heights at South Beach, assuming an “L”-sized earthquake, is also presented to better estimate the inundation levels several kilometers inland at the old-growth site. This tsunami model indicates the South Beach fir stand would have been subjected to local inundation depths from 0 to 10 m. Growth chronologies collected from the Douglas-fir stand shows that trees experienced a significant growth reductions in the year 1700 relative to nearby Douglas-fir stands, consistent with the tsunami inundation estimates. The ±1–3-year timing of the South Beach disturbances are also consistent with disturbances previously observed at a Washington state coastal forest ∼220 km to the north. Moreover, the 1700 South Beach growth reductions were not the largest over the >321-year tree chronology at this location, with other disturbances likely caused by climate drivers (e.g., drought or windstorms). Our study represents a first step in using tree growth history to ground truth tsunami inundation models by providing site-specific physical evidence.
• Keywords:
  Earthquakes Tsunamis Distrubance History Innundation Tree Ring Growth
• Source:
  Nat. Hazards Earth Syst. Sci., 21, 1971–1982
• DOI:
  https://doi.org/10.5194/nhess-21-1971-2021
• Document Type:
  Journal Article
• Place as Subject:
  Oregon
• Rights Information:
  CC BY
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha256:679bc159ee5f88fc82bbce4c4a19fdb9f4fd164f16d5e2c3ee0b093948733200
• Download URL:
  https://repository.library.noaa.gov/view/noaa/33423/noaa_33423_DS1.pdf
• File Type:
  [PDF - 12.80 MB ]