calm

wind force

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June 17, 2026

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The Beaufort scale is a system used to measure wind force. It ranges from 0 to 12, with each number representing a different wind speed and its effect on the sea and land.12

A Beaufort number of 0 indicates "calm," meaning there is no wind or the wind speed is no more than one mile per hour. This condition is characterized by a sea surface like a mirror. As the Beaufort number increases, so does the wind speed, leading to more significant effects on the water, such as ripples, small waves, and eventually large waves with foam and spray. While the scale was originally based on observations of sailing ships, it has been correlated with actual wind speeds and is still useful for estimating wind characteristics over large areas, especially where instruments are unavailable.321

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