Wave heights
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Hi - I have a few questions about wave heights using the ECMWF model... Firstly is the wave height given in the table a combination of the wind waves and the swell or is it just the wind waves? Secondly, does the wave model include tidal effects such as the steepening of waves when a strong tide is flowing in the opposite direction to the wind. Finally, a suggestion... when looking at waves "weather vane" shown on the chart gives the wind speed plus height and period for swell 1 and swell2. I think it would be more useful if it showed the wind wave height and period, instead of (or maybe in addition to) the wind speed.
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@johnbrownridge
Waves height is not only the height of wind waves as explained here :
https://community.windy.com/topic/17449/swell?_=1693652531409
I don't think the sea surface currents are integrated in the wave height calculation by ECMWF.
https://confluence.ecmwf.int/display/FUG/Section+2.2+Ocean+Wave+Model+-+ECWAM#Section2.2OceanWaveModelECWAM-Sea-surfacecurrents
And it is sure that the waves height prediction does not include the effect of local tidal currents which are usually strong near the coast, in some narrow straits, specially when wind and current are opposite.
The arrows shown with the Waves diagram are mainly design for surfers / windsurfers. They are most interested in swell than wind waves and I don't think that wind waves period is really interesting or useful… or for which activity? -
@idefix37 Many thanks that's a very helpful explanation. For the wind waves on the weather vane I thought it might be useful for sailing to make it easier to see wave components are the most dominant at any one time.
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@johnbrownridge
For sailing, knowing Waves height (of the total sea)and period is more important than wind waves. Wind waves are just a component of the total sea. But it is important to know the wind waves direction and that of the different swells. They can be opposite 180° or cross 90°. A cross sea is much more dangerous and tough than wind waves and swells in same direction, even if higher.
