ecCodes definition

Name:Significant height of combined wind waves and swellAbbreviation:swhUnit:mparamId:140229


Other details

DefinitionBetter known as the Significant Wave Height. The significant wave height is defined as 4 times the square root of the integral over all directions and all frequencies of the two-dimensional wave spectrum. The integration is performed over all frequencies up to infinity.
Validityinstantaneous
Comment Missing values should be encoded as bitmap.


WMO GRIB2 definition

Parameter
Discipline10oceanographic products
Parameter category0waves
Parameter number3

Significant height of combined wind waves and swell

Level
Type of first fixed surface1ground or water surface
Scale factor of first fixed surfaceall bits to 1missing
Scaled value of first fixed surfaceall bits to 1missing
Type of second fixed surfaceall bits to 1missing
Scale factor of second fixed surfaceall bits to 1missing
Scaled value of second fixed surfaceall bits to 1missing