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Tidetech Environmental Data - Parameters and Units

Weather – short term response of the atmosphere to solar heating and Earth rotation

  • Winds at 10m above the sea surface

    • windspeed – ms-1 or knots

    • wind direction – degrees relative to true North (direction from)

    • east wind – ms-1 wind towards East

    • north wind – ms-1 wind towards North

    • gust – ms-1, maximum instantaneous wind speed in a period

  • Atmospheric pressure – Pa (hPa = mbar), air pressure at mean sea level

  • Air temperature – degrees Celcius (C) at 2m above the surface (or degrees Kelvin (K) … C = K - 273.15)

  • Relative Humidity - % at 2m above the surface, a measure of the amount of water vapour in the air

  • Cloud cover – fraction between 0 (no cloud) and 1 (total cloud cover)

  • Visibility – m, distance view at the surface

  • Precipitation – mm/day, accumulated rainfall

 

Currents

  • Tides – generated by the gravitational attraction between the Earth, the Moon and Sun

    • tidal current speed – ms-1 or knots

    • tidal current direction – degrees relative to true North (direction to)

  • Ocean currents – response to atmospheric forcing and differences between water masses in polar and equatorial regions

    • current speed – ms-1

    • current direction - degrees relative to true North (direction to)

  • Coastal currents – response to atmospheric forcing, river inflows and topographic steering

    • current speed – ms-1

    • current direction - degrees relative to true North (direction to)

  • Stokes drift – currents associated with surface wave propagation

    • current speed – ms-1

    • current direction - degrees relative to true North (direction to)

 

Surface waves – generated by the action of winds on the sea surface

  • Significant wave height – m, the mean of one third of the highest waves in a given period

  • Peak wave period – seconds, the period of the wave spectral peak

  • Peak wave direction – degrees relative to true North (direction from) of the wave spectral peak

  • Wind wave height – m, the mean wave height driven by local winds in a given period

  • Wind wave period – seconds, the period of the mean wind wave periods

  • Wind wave direction – degrees relative to true North (direction from) of the mean wind wave

  • Swell wave height – m, the mean swell wave height of the major (primary) swell component in a given period

  • Swell wave period – seconds, the period of the mean swell wave periods

  • Swell wave direction – degrees relative to true North (direction from) of the mean swell waves

 

Oceanographic – other parameters

  • Sea Surface Temperature - degrees Celcius (C), the foundation temperature of the sea surface layer

  • Sea Surface Salinity – salinity units (psu), saltiness of the sea water at the sea surface

  • Sea surface height – m, ocean sea surface height above the geoid

  • Tidal elevation – m, tidal sea surface height above mean sea level

  • Chlorophyll_a – mgm-3, values of mass concentration of chlorophyll_a, an indication of primary production

  • Sea ice fraction – fraction between no ice (=0) and total ice coverage (=1); all ice floating in the sea which has formed from freezing sea water

  • Sea ice thickness – m, vertical extent of ice floating in the sea which has formed from freezing sea water