Tide currents
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Se have been in Shetland last week and while tide height and hour seems ok, tidal currents (ej. at Papa Stour Sound / Channel) are way out of what charts suggest (like 0.7kt to 5kt). Same thing seems near Paimpol.
Really is difficult to know which is OK. Is this a bug or simply the detail is not enough?
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In straits, estuaries or narrow channel, the Tidal current layer may provide underestimated speed.
Tidal currents data in Windy is based on the variation of sea surface altimetry measured by satellites (From CMEMS Copernicus Marine Environment Monitoring Service).
From this data which gives the sea surface level, tidal currents are computed.
The satellite data resolution is 0.25° x 0.25° or 15NM x 15NM. That is enough to estimate correctly the sea surface level excepted in closed, long or narrow bays. In fact the tidal currents speed depends also on coast line and seabed mapping. So in some areas these currents are probably underestimated. -
Same thing seems near Paimpol.
You are right. Compared to the tidal currents provided by Ifremer at the same date/time, those from Windy present a lower resolution in this area and, above all, an erroneous speed and direction along the coastline, particularly in Le Trieux estuary. A current perpendicular to the axis of the estuary is unrealistic.
