4/12/2016
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Wave definition, types of waves, orbital waves
Why study waves?
Wave parts, anatomy of a wave
How waves begin, generating force, restoring force
Wave Speed: R=D/T or C=L/T, Celerity
Water motion in waves
Wave base, L/2
Deep water waves, intermediate and shallow water waves
Wind generated waves, H dependent on WfD
Wave types: Sea, Swell and Surf
Waves as they approach the shore: refraction, diffraction and reflection
Canyon divergence and headland convergence
Sea caves, arches and sea stacks
Wave generated currents: longshore and rip
Standing waves: nodes and antinodes, seiches
Catostrophic waves: storm surges and tsunamis
Mega tsunamis: know H, L and P of a typical seismic sea wave!
Internal waves
1
4/12/2016
2
4/12/2016
Fig. 19‐8, p.571
3
4/12/2016
Standing Waves
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Wave definition, types of waves, orbital waves
Why study waves?
Wave parts, anatomy of a wave
How waves begin, generating force, restoring force
Wave Speed: R=D/T or C=L/T, Celerity
Water motion in waves
Wave base, L/2
Deep water waves, intermediate and shallow water waves
Wind generated waves, H dependent on WfD
Wave types: Sea, Swell and Surf
Waves as they approach the shore: refraction, diffraction and reflection
Canyon divergence and headland convergence
Sea caves, arches and sea stacks
Wave generated currents: longshore and rip
Standing waves: nodes and antinodes, seiches
Catostrophic waves: storm surges and tsunamis
Mega tsunamis: know H, L and P of a typical seismic sea wave!
Internal waves
Hurricanes cyclones and storms bring waves and coastal flooding
Hurricane Andrew
https://www.youtube.com/watch?v=bYI1zIjJr4g
STORM SURGES
4
4/12/2016
Hurricane Katrina
8/28/05
Storm in Bangladesh in April 1991
~138,000 killed, 10 million left homeless, 6 meter storm surge goes inland, 1.5 billion in damage
Superstorm Sandy 10/28/12
Typhhon Haiyan 11/8/13
5
4/12/2016
http://ulithimarineconservation.ucsc.edu/
Tsunami reporting stations and subduction zones
Tsunamis
DART: Deep‐Ocean Assessment and Reporting of Tsunamis 6
4/12/2016
9.1 – 9.3 Magnitude Sumatran Earthquake Dec. 26, 2004
Areas at Risk
Hawaii
Alaska
California
East Coast US?
– Gulf Coast US?
–
–
–
–
• Plates‐Boundary Type
• Depth: 30km
• Rupture Length and shaking duration: ~1,300Km (810mi), over 4 min in 1 area, up to 10min total
• Displacement: lateral ~20m, vertical 2‐5m
• Energy Released: ~475 megatons of TNT or 23,000 A‐Bombs
Earthquake activity in Japan from 1990 to 2011
https://www.youtube.
com/watch?v=Yl08jK4
ci2g&feature=relmfu
7
4/12/2016
Capitola
California
March 11, 2011
Reducing Tsunami Hazards
• Warning system in all major oceans
• Local gov’t evacuation routes and procedures
• Education about warning signs
– Ground‐shaking in coastal areas
– Unusual disturbance of ocean
– Move to high ground (several hours‐days)
– First wave generally not largest
– https://www.youtube.com/watch?v=qFKgQwou7ls
Surfing calving glaciers
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Wave definition, types of waves, orbital waves
Why study waves?
Wave parts, anatomy of a wave
How waves begin, generating force, restoring force
Wave Speed: R=D/T or C=L/T, Celerity
Water motion in waves
Wave base, L/2
Deep water waves, intermediate and shallow water waves
Wind generated waves, H dependent on WfD
Wave types: Sea, Swell and Surf
Waves as they approach the shore: refraction, diffraction and reflection
Canyon divergence and headland convergence
Sea caves, arches and sea stacks
Wave generated currents: longshore and rip
Standing waves: nodes and antinodes, seiches
Catostrophic waves: storm surges and tsunamis
Mega tsunamis: know H, L and P of a typical seismic sea wave!
• Internal waves
8
4/12/2016
Small Internal Wave in Monterey Bay, 2008
Figure 10_28
Internal Waves: can have L of 100’s of Ms to 10’s of Kms
H often >50m, T could be from 20 min to a few hrs.
Fig. 10.26
9