CH1WAVE Flashcards
(31 cards)
What is wavelength (L)?
Distance between two consecutive crests.
What is wave height (H)?
Vertical distance from crest to trough.
What is wave amplitude (A)?
Half the wave height.
What is wave period (T)?
Time between two crests.
What is wave frequency (F)?
Number of waves passing a point per unit time.
What is wave celerity (C)?
Speed of wave crest movement.
wave types based on depth
Shallow water waves: d/L < 0,05
Intermediate water waves: 0,05 < d/L < 0,5
Deep water waves: d/L > 0,5
particle motion in deepwater?
In a circular orbits,
orbit size decreases with depth.
particle motion in shallow water?
orbits become elliptical as Bottom interaction occurs.
wave types based on movement?
Progressive waves:
- crest moves forward
- water particles move in a circular paths
Standing waves:
- crest moves up and down
- have nodes and antinodes
What is the wave behavior near the shore?
Decrease in depth, celerity, and wavelength; increase in height and steepness.
leads to wave breaking near the shore
what are the level variations in real life
- astronomical tides
- atmospheric pressure
- winds (storm urges)
- precipitation
- water density
- seiches
- tsunamis
astronomical tides?
- Gravitational pull of sun and moon.
- sime diurnal
- 0,2 to 10 m
atmospheric pressure?
- strong pressure gradients cause noticeable sea level changes
- hours to months
- -0.7 TO 1.3 m
Winds
- wind pushes water toward coastlines, raising water levels significantly during storms
- several days
- up to 5m
precipitation?
- Heavy rain or long term snow melts can raise sea level.
- days to weeks
- several meters
water density
- driven by changes in salinity and temperature
- seasonal
- 0.2 m
the fetch area:
An area over a water surface where wind blows consistently, creating waves through friction and making the surface chaotic and irregular.
the swell area:
- Refers to the organized waves that move away from the fetch area
- smoother, more regular, and able to travel long distances even after the wind stops.
wave types by period:
capillary: < 0.1 s
chop: 0.1 - 1s
swell: 5 - 20 s
seiche: Minutes to hours
tsunamu: 5min - 2hours
tide: 12 - 25 hours
chop wave
Short, irregular waves formed by local winds.
What are capillary waves?
Small ripples on the water surface created by light wind and held together by surface tension.
What are seiches?
a standing wave that forms in an enclosed or semi enclosed basin, like a lake, bay, or harbor.
What are tsunamis?
- long-period waves caused by sudden disturbances on the seafloor
- often silent and unnoticed at sea but catastrophic near shore,
