Escala Douglas - altura onades
Escala Douglas
| Grau | Nom | Altura de les onades (m) |
|---|---|---|
| 0 | Mar plana | 0 |
| 1 | Mar arrissada | 0 - 0.1 |
| 2 | Marejol | 0.1 - 0.5 |
| 3 | Maror | 0.5 - 1.25 |
| 4 | Forta maror | 1.25 - 2.5 |
| 5 | Maregassa | 2.5 - 4 |
| 6 | Mar brava | 4 - 6 |
| 7 | Mar desfeta | 6 - 9 |
| 8 | Mar molt alta | 9 - 14 |
| 9 | Mar enorme | >14 |