Coastal Effects of Tsunamis
PI: Harry Yeh Proj. No. R/CNH-‐20
ObjecDves
To gain a beGer understanding of tsunami characterisDcs and behavior.
• It will lead to the improvement of tsunami inundaDon models.
• The improved inundaDon models will then yield more accurate evacuaDon maps.
• The evacuaDon maps are essenDal for beGer preparaDon and planning, thereby reducing damage and loss of lives from tsunami disasters.
80% Prob
95% Prob
Current Tsunami InundaDon Maps
Local Tsunami Runup (Inaho Coast, the 1993 Okushiri)
Local Tsunami Runup (Laboratory Model of Monai)
PredicDon & Measurement
Three Primary Research AcDviDes
1. Explore the basic understanding of long-‐wave (tsunami) characterisDcs and behaviors in the laboratory-‐scale environment.
2. Promote advances in mathemaDcal theories relevant to tsunami phenomena.
3. Help improve tsunami-‐inundaDon numerical models used in real-‐world applicaDons.
My Ongoing Research R/CNH-‐17: Localized Extreme Tsunami Runup
Wenwen Li – Graduate student
Mach ReflecDon
Field ObservaDons of the Mach ReflecDon
The 1946 AlueDan Tsunami in Hilo, HI.
An edge wave propagaDng a canal
Field ObservaDons of the Mach ReflecDon
Wave Tank in Graf Hall, OSU
Wave paddles driven by 16 linear motors
Wave padd
les
3.6 m
0.3 m
7.3 m
7.3 m
Our Laboratory RealizaDon of the Mach ReflecDon
Laser Induced Fluorescent Technique
Repeatability
Maximum error is less than 0.06 mm
Wave Profiles in the DirecDon Normal to the Wall
h0 = 6.0 cm; = 30˚; ai = 0.182 (1.09 cm); x = 71.1 (427 cm)
Temporal profiles
ψ i
Wave Profiles in the DirecDon Normal to the Wall
Meniscus effect
h0 = 6.0 cm; = 30˚; ai = 0.182 (1.09 cm); x = 71.1 (427 cm)
Temporal profiles
ψ i
Temporal VariaDon of Measured Water-‐Surface
Capillary-‐Gravity Waves
(t – y plane; the wall at y = 0)
αw = 2.26
α r = 0.61
h0 = 6.0 cm; ψ i = 30˚; ai = 0.182; x = 71.1
Stem Wave AmplificaDon
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4
Series1
Series2
Loc7_30deg
Loc7_20deg
Loc6_40deg
k
αw
theory
Breaking Stem Wave
h0 = 6.0 cm; = 30˚; ai = 0.37
at x = 60.96
at x = 71.7
ψ i
Research Tasks
1. ReflecDve characterisDcs of tsunamis from the land, and the effects of local variaDons in bathymetry on tsunami amplificaDon
2. Effects of local currents (e.g. Columbia River) on tsunami transformaDon.
3. RealizaDon of the predicDons from mathemaDcal theories.
4. Organize a 2-‐day workshop at Oregon State University for model validaDon specifically aimed at the inundaDon models used in NTHMP (NaDonal Tsunami Hazard MiDgaDon Program).
Collaborators and/or Contributors
• NTHMP tsunami inundaDon model: Dr. Yinglong (Joseph) Zhang of the Center for Coastal and Land-‐Margin Research: link to NTHMP.
• Boussinesq model: Dr. Patrick LyneG of Texas A&M University: link to “COULWAVE” a high-‐end numerical code used in pracDce.
• MathemaDcal analysis: Dr. Yuji Kodama of Ohio State University.
• ParDcipants of the proposed workshop in Year 2.
Ongoing Research with Kodama
Kodama’s TheoreDcal PredicDon
Ongoing Research with Kodama
Kodama’s TheoreDcal PredicDon
Our Laboratory RealizaDon
This can be used for outreach and educaDon
Strong InteracDon of Two Solitons
Strong InteracDon of Two Solitons
5 7 6
4 3 2 1
Outreach & EducaDon
• The video and other visuals will be disseminated through a variety of means: classroom use, sharing the materials via Internet (website), exhibit at the Harield Marine Science Center, and via Sea Grant Extension.
• Work with the staff at Oregon Sea Grant Office for its producDon and disseminaDon.
Outreach & EducaDon
• The video and other visuals will be disseminated through a variety of means: classroom use, sharing the materials via Internet (website), exhibit at the Harield Marine Science Center, and via Sea Grant Extension.
• Work with the staff at Oregon Sea Grant Office for its producDon and disseminaDon.
hGp://web.engr.oregonstate.edu/~liw/Website_Yeh/