Sea Surface State (MS) Is Determined Visually and Depends Upon Wind Force. Wind Force

Steve,

Sea surface state (MS) is determined visually and depends upon wind force. Wind force is visually described both in words and in Beaufort wind scale numbers (Forces).

We have made an attempt to review manuals and guides on ship wind observations and so far managed to find the only one, namely, “Instructions to hydrometeorological stations and posts”(Issue 9, Part 2, 1948), which gives the joint table of wind force and sea surface state described by the so-called Beaufort-Simpson scale (Table 1). This table was used in Russian observations to estimate both wind force and the MS parameter.

In the period of 1962-1992 the same Beaufort scale was used and word description of indicators required to define the surface state of an ocean, sea, lake or large water body (MS) corresponds to that given in Table 3, which we included into the format.

Since 1992 the Beaufort scale has been modified. Wind speed increased and the corresponding wind force given in numbers remained unchanged (Table2).

In original historical tables the MS parameter has already been encoded and given in numbers.

Russian national manuals on ship observations do not mention that Beaufort scale should be used to estimate MS. They give only Table 3, which we include into the format.

In my opinion, when MS is converted to wind force Beaufort scale used at the time, when observations were made, should be applied.

The digitization work is go on OK. At present time we prepare 100 cruises-files with meteorological and actinometric observations and forwarding to NCAR in a week.

Regards,

Svetlana

Table 1

Wind force, wind speed and sea surface state

Wind force

Table 2

Beaufort scale to estimate wind force

Code. Table 3. Sea Surface State (MS).

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