Charterparty

Compiled by Arun Kasi

Last Updated 4th May 2021

 

DOUGLAS SEA STATE SCALE and WMO CODE TABLE 3700 

(SEA STATE/WAVE HEIGHT MEASUREMENT)

Douglas Sea State

(as adopted by the International Meteorological Organisation in 1929)

 

WMO Code Table 3700

Code

Description

 

 

 

 

0

Calm 

1

Smooth

2

Slight

3

Moderate

4

Rough 

5

Very rough

6

High

7

Very high

8

Phenomenal

9

Confused

Code

Description

Height (m)

 

 

 

0

Calm (glassy)

0

1

Calm (rippled)

0 - 0.1

2

Smooth (wavelets)

0.1 - 0.5

3

Slight

0.5 - 1.25

4

Moderate

1.25 - 2.5

5

Rough 

2.5 - 4

6

Very rough

4 - 6

7

High

6 - 9

8

Very high

9 - 14

9

Phenomenal

> 14

 

BEAUFORT SCALE (WIND MEAUREMENT)

Beaufort Scale

(as presently adopted by the UK Met Office – specs for observation added)

Scale

Mean Wind Speed

Limits of wind speed

Wind descriptive terms / specs for observation on board ship in open sea

Probable wave height

Probable maximum wave height

Sea State

 

Knots

ms-1

Knots

ms-1

 

in metres

in metres

 

0

0

0

<1

<1

Calm

(Sea like a mirror)

-

-

0

1

2

1

1-3

1-2

Light air

(Ripples with the appearance of scales are formed, but without foam crests)

0.1

0.1

1

2

5

3

4-6

2-3

Light breeze

(Small wavelets, still short but more pronounced; crests have a glassy appearance and do not break)

0.2

0.3

2

3

9

5

7-10

4-5

Gentle breeze

(Large wavelets; crests begin to break; foam of glassy appearance; perhaps scattered white horses)

0.6

1.0

3

4

13

7

11-16

6-8

Moderate breeze

(Small waves, becoming longer; fairly frequent white horses)

1.0

1.5

3-4

5

19

10

17-21

9-11

Fresh breeze

(Moderate waves, taking a more pronounced long form; many white horses are formed [chance of some spray])

2.0

2.5

4

6

24

12

22-27

11-14

Strong breeze

(Large waves begin to form; the white foam crests are more extensive everywhere (probably some spray])

3.0

4.0

5

7

30

15

28-33

14-17

Near gale

(Sea heaps up and white foam from breaking waves begins to be blown in streaks along the direction of the wind)

4.0

5.5

5-6

8

37

19

34-40

17-21

Gale

(Moderately high waves of greater length; edges of crests begin to break into the spindrift; the foam is blown in well-marked streaks along the direction of the wind)

5.5

7.5

6-7

9

44

23

41-47

21-24

Strong gale

(High waves; dense streaks of foam along the direction of the wind; crests of waves begin to topple, tumble and roll over; spray may affect visibility)

7.0

10.0

7

10

52

27

48-55

25-28

Storm

(Very high waves with long overhanging crests; the resulting foam, in great patches, is blown in dense white streaks along the direction of the wind; on the whole, the surface of the sea takes a white appearance; the tumbling of the sea becomes heavy and shock-like; visibility affected)

9.0

12.5

8

11

60

31

56-63

29-32

Violent storm

(Exceptionally high waves (small and medium-sized ships might be for a time lost to view behind the waves); the sea is completely covered with long white patches of foam flying along the direction of the wind; everywhere the edges of the wave crests are blown into front; visibility affected)

11.5

16.0

8

12

-

 

64+

33+

Hurricane

(The air is filled with foam and spray; sea completely

white with driving spray; visibility very seriously affected)

14+

-

9

 

Dr. Arun Kasi

LLB (Hons), LLM, CLP, Barrister, FCIArb (London), PhD

Nicole Lee Hui Ching

LLB (Hons)

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