Waves 2 Flashcards
Sea state is the ___ at sea
degree of turbulence
What three things are needed to get BIG waves?
- Fast wind speed
- Sustained wind (blow for long time)
- Long fetch
Long fetch
large, uninterrupted distance (fetch) over which wind blows
As wind speed, blowing time, or long fetch increases, what happens to the waves?
- more energy is added
- wave height increases = bigger waves
The Beaufort scale rates ___
relates wind speeds
to observed conditions at sea & on land
- from 0 to 12
Waves develop in a ___ sea state
turbulent
Is there a maximum sea state?
Yes
- the fully developed sea
In a fully developed sea, there is a practical limit for ___
EVERY wind speed
The practical limit for a wind speed means that
extra time or distance will NOT produce larger waves
The biggest wind waves are found in ___ because ___
Southern ocean around Antarctica
- cuz nothing affects their flow = large fetch
How big are wind waves usually in the open ocean?
About 2-6m height
What happens when waves become too steep in the open ocean?
they become unstable and break or fall over
How can we calculate when a wave will break?
steepness (H/L) > 1/7 (0.14)
Wind waves may have wavelengths of up to ___ meaning they will break at max ___ m high
- L about 150 m
- break at 21m
Swells are waves that move ___ a storm region and can travel distances of ____
- away from
- thousands of km
