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Significant wave height and mean direction

Base Time: Tue 27 Jul 2021 00 UTC T+24 Valid time: Wed 28 Jul 2021 00 UTC

At any location over the oceans, a wave field is fully characterised by its 2-dimensional wave spectrum which describes how much wave energy is present for given frequencies and propagation directions. This comprehensive representation is simplified in a set of integrated parameters:
The significant wave height is defined as 4 times the square root of the integral over frequency and direction of the wave spectrum.
The mean wave direction is the spectrally averaged propagation direction of the waves.

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ECMWF Newsletter 168

Summer 2021 Newsletter published

The summer 2021 issue of the ECMWF Newsletter is now available. As well as news about ECMWF staff and events, it features articles about new developments and the use that can be made of ECMWF products.

23 July 2021

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ECMWF has implemented an upgrade of its Integrated Forecasting System, including a move from double to single precision and an increase in the vertical resolution of ensemble forecasts. #IFS47r2 #newfcsystem Find out more here:


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