Waves
Swell, Surf, and Tides
Topics
• Factors That Determine H
• Wave Interference
• Wave Dispersion
• Surf
• Wave Refraction
• Longshore Drift
• Longshore Current
• Wave Reflection and Seawalls
Topics
• Factors That Determine H
• Wave Interference
• Wave Dispersion
• Surf
• Wave Refraction
• Longshore Drift
• Longshore Current
• Wave Reflection and Seawalls
Factors That Determine
Wave Height
Factors That Determine
Wave Height
Big winter waves and small summer waves
Factors
Factors
Three primary factors determine wave height:
Factors
Three primary factors determine wave height:
1.
Wind speed
Factors
Three primary factors determine wave height:
1.
Wind speed
2.
Fetch
Factors
Three primary factors determine wave height:
1.
Wind speed
2.
Fetch
3.
Duration
Wind Speed - the faster the wind, the greater the wave height
Duration
Duration
Duration - time the wind blows in one direction
Duration
Duration - time the wind blows in one direction
The longer the duration, the greater the wave height
Fetch
Fetch
Fetch - distance the wind blows in one direction
Fetch
Fetch - distance the wind blows in one direction
The longer the fetch, the greater the wave height
Low pressure system over Iceland
Fully-Developed Sea
Fully-Developed Sea
When maximum fetch and maximum duration are reached, a
sea is fully developed for a given wind speed
Fully-Developed Sea
When maximum fetch and maximum duration are reached, a
sea is fully developed for a given wind speed
In a fully-developed sea, significant wave height solely is a
function of wind speed
Fully-Developed Sea
When maximum fetch and maximum duration are reached, a
sea is fully developed for a given wind speed
In a fully-developed sea, significant wave height solely is a
function of wind speed
Significant wave height - average height of the largest 1/3 of
the waves
Sunset Beach
Significant Wave Heights for
Fully-Developed Seas
Wave heights generally are limited by fetch or duration
Hurricane Tracks
Big Waves
Largest Measured Wave
Next
Wave Interference
Significant Wave Height
Significant Wave Height
Significant wave height - average height of the largest 1/3 of
the waves
Significant Wave Height
Significant wave height - average height of the largest 1/3 of
the waves
Normally determine wave heights using the largest waves