Humboldt Bay Vertical Reference System Working Group (HumBayVert)

Humboldt Bay Initiative Meeting: June-24-2014

Cascadia GeoSciences, Northern Hydrology, HSU Geology, U of O Geology, & HBI members

http://hbv.cascadiageo.org

Background• Partnerships• Issues• Goal• Funded by NPLCC

Update• 2013 Annual Report• Trinidad Tide Gage Installation• SLR Calculations

Next Step• Predictive Model• Tectonic Modeling• Need Funding

http://hbv.cascadiageo.org

PartnershipsCascadia GeoSciencesHumboldt Bay Initiative

“Our vision is a vibrant, thriving, and resilient Humboldt Bay Ecosystem that supports the well-being of our human and natural communities.”North Pacific Landscape Conservation CooperativeDept. of Interior Climate Change Adaptation Program

Issue: tectonics controls Local Sea Level

Accurate measurement of local land elevation in the Humboldt Bay area

Priority issue identified by USACE, Coastal Commission, NOAA NGS & others

We live and work here!

Atwater & Satake, 2009

Interseismic between earthquakes

Coseismic during earthquake

Subduction Zone Earthquake Cycle and Vertical Land Level Changes:

Eustatic SeaLevel Rise

(ESLR)

TideGauges

Leveling & GPS

Compare Rates & Test Observations

Compare to tide gageobservations

Compare to GPS and land level surveys

Compare to long term ESLR

Historic Temporary Tide Gage LocationsHumboldt Bay 1977-1980

Mad River Slough

North Spit

Hookton Slough

Samoa

Fields Landing

North Pacific Landscape Conservation Cooperative funded this research project through the USFWS, Award F11AC01092

Trinidad Tide Gage• We are purchasing equipment that will be

installed and maintained by CenCOOS• Equipment will be installed in July 2014• Level Survey will be completed in July 2014

Historic Benchmark Surveys (1988-1968)

Reed Burgette, 2012;Univ. of Oregon

Draft Humboldt Bay Vertical Land Motion Estimates

SLR and VLM Rates (mm/yr)Tide Station (TS) Note Datum ReSLR RSLR TS-CC VLM

Crescent City (CC)Long Term Tide Station with

Mean Monthly Seasonal Cycle Removed

STND 2.28 -0.92 3.20

North Spit (NS)Reference Humboldt Bay Tide Station with Mean Monthly

Seasonal Cycle RemovedSTND 2.28 4.83 5.75 -2.55

Mad River Slough (MRS) Minor Tide Station NAVD88 2.28 3.28 4.2 -1.00

Somoa (SO) Minor Tide Station STND 2.28 2.58 3.50 -0.30

Fields Landing (FL) Minor Tide Station STND 2.28 3.53 4.45 -1.25

Hookton Slough (HS) Minor Tide Station STND 2.28 5.88 6.80 -3.60

ReSLR = regional sea level rise rate

RSLR = relative sea level rise rate

SLR = sea level rise rateVLM = vertical land motion

Jeff Anderson

40.640.841.041.241.441.641.842.0-4

0

4

R² = 0.882233203842251

Vertical Land Motion

Tide Gage SitePolynomial (Tide Gage Site)

Latitude (deg)

VLM

mm

/ y

r

40.640.841.041.241.441.641.842.0-4

0

4

f(x) = − 7.31644010271352 x² + 608.811334384709 x − 12661.6893706718R² = 0.891856839509725

Vertical Land Motion

Tide Gage SitePolynomial (Tide Gage Site)

Latitude (deg)

VLM

mm

/ y

r

Jeff Anderson

Next Step• Tectonic Modeling• Fit tectonic model to tide gage and BM data• Prepare Predictive Model• Project Proposal is Written (but not funded yet)

Kriging IDW

Mission and Goals• Determine historic land and sea level trends • Map local sea level change across region• Complete historic analysis of tide and level data in PNW• Model geologic processes controlling uplift/subsidence• Compare historic trends to prehistoric geologic record• Data dissemination for regional workers

Methods• Re-occupy historic tide gage locations• Install regional tide gage stations• Collect and analyze historic GPS & level data WRT mean sea

level• Model Cascadia subduction zone with new data• Partnerships & collaboration

END

Jeff Anderson

Jeff Anderson

Jeff Anderson

Jeff Anderson

Jeff Anderson

Jeff Anderson

Jeff Anderson