"A period is an interval of time, or the time-period of an oscillation. Swell waves are waves on the ocean surface."@en . . . . "SDN:P07::CFSNA027" . "1" . "2006-09-26 18:12:43.0" . "swell_wave_period"@en . "SDN:P07::CFSNA027" . . . "true" . "2006-09-26 18:12:43.0" . . "SDN:P07::CFSNA027" . . . "deprecated"@en . . . . "1" . "" . . . .