How to calculate the combined sea and swell height

Use this table to calculate the combined sea and swell height.

 
SWELL HEIGHT (metres)

0

0.5

1.0

1.5

2.0

2.5

3.0

4.0

5.0

6.0
7.0
8.0
WAVE HEIGHT (metres)
0.5

0.5

0.7

1.1

1.6

2.1

2.6

3.0

4.0

5.0

6.0

7.0

8.0

1.0

1.0

1.2

1.4

1.8

2.2

2.7

3.2

4.1

5.1

6.1

7.1

8.1

1.5

1.5

1.6

1.8

2.1

2.5

2.9

3.4

4.3

5.2

6.2

7.2

8.1

2.0

2.0

2.1

2.2

2.5

2.8

3.2

3.6

4.5

5.4

6.3

7.3

8.2

2.5

2.5

2.6

2.7

2.9

3.2

3.5

3.9

4.7

5.6

6.5

7.4

8.4

3.0

3.0

3.0

3.2

3.4

3.6

3.9

4.2

5.0

5.8

6.7

7.6

8.5

4.0

4.0

4.0

4.1

4.3

4.5

4.7

5.0

5.7

6.4

7.2

8.1

8.9

5.0

5.0

5.0

5.1

5.2

5.4

5.6

5.8

6.4

7.1

7.8

8.6

9.4

6.0

6.0

6.0

6.1

6.2

6.3

6.5

6.7

7.2

7.8

8.5

9.2

10.0

7.0

7.0

7.0

7.1

7.2

7.3

7.4

7.6

8.1

8.6

9.2

9.9

10.6

8.0

8.0

8.0

8.1

8.1

8.2

8.4

8.5

8.9

9.4

10.0

10.6

11.3

9.0

9.0

9.0

9.1

9.1

9.2

9.3

9.5

9.8

10.3

10.8

11.4

12.0

10.0

10.0

10.0

10.0

10.1

10.2

10.3

10.4

10.8

11.2

11.7

12.2

12.8

About the calculation

The table above was calculated using the following formula.

Combined sea and swell height = [(Wind Wave Height)2 + (Swell Wave Height)2]1/2

About the values in this table

The Bureau provides forecasts of swell and sea to the nearest 0.5m. To be consistent with this precision, the total wave height values in the above table should be "rounded" to the nearest 0.5m.