How Ocean Waves Are Measured and Forecast
Follow buoy motion, wave spectra, winds and numerical models from individual observations to a forecast sea state.
Explore wave observationsWhat the data really means
Use these four anchors before interpreting the related live visualization.
- Buoy motion
- Acceleration and displacement at one location
- Wave spectrum
- Energy distributed by frequency and direction
- Significant height
- Statistical summary of the sea state
- Forecast
- Wind-forced numerical wave model
From evidence to the PlanetVexa view
Each stage changes what can be claimed. PlanetVexa keeps the source record, derived interpretation and visual presentation visibly distinct.
- 01Buoy motion
Acceleration and displacement at one location
- 02Wave spectrum
Energy distributed by frequency and direction
- 03Significant height
Statistical summary of the sea state
- 04Forecast
Wind-forced numerical wave model
A buoy turns motion into wave statistics
Accelerometers, inclinometers or GPS sensors record how a buoy moves with the surface. Processing separates wave frequencies and can estimate height, period and direction over a sampling interval. Mooring response, currents, sensor limits and data quality flags affect the result.
The reported significant wave height summarizes the highest-energy portion of a statistical sea, not the height of every crest passing the buoy.
The spectrum explains a mixed sea
A wave spectrum distributes energy by frequency; directional systems also estimate where that energy travels. Local wind sea can overlap with one or more swell systems generated far away. Peak period identifies the most energetic frequency, while mean periods answer different statistical questions.
Two locations with the same significant height can feel very different when period, direction, steepness and crossing seas differ.
Models evolve waves under wind and ocean physics
Operational wave models use analyzed and forecast winds to grow, propagate and dissipate spectral wave energy. Coastlines, depth and currents influence regional behavior, and nested grids can add detail near shore. Buoys, satellites and other observations support evaluation and data assimilation.
A model cell is a forecast for an area and valid time, not an observation from the displayed coordinate. Ensemble spread can reveal forecast sensitivity.
Near-shore conditions need local transformation
As waves enter shallow water they refract, shoal, break and interact with complex bathymetry, tides and currents. An offshore buoy or global model cannot describe every beach, harbor entrance or vessel response. Official marine forecasts and local authorities add operational context.
PlanetVexa preserves height, period, direction, source and valid time, and avoids turning one offshore number into a universal safety judgement.
Questions people ask
Is significant wave height the largest wave?
No. It is a statistical sea-state measure; individual waves can be appreciably higher.
Why can swell arrive after the local wind calms?
Wave energy propagates away from its generating storm and can travel long distances as swell.
Does an offshore wave forecast describe conditions at the beach?
Not exactly. Bathymetry, currents, tides and coastal orientation transform waves near shore.
Read the official material
PlanetVexa summarizes these sources in original language and links to the responsible institutions for definitions and operational context.