One of the first scales to estimate wind speeds and the effects was created by Britain's Admiral Sir Francis Beaufort (1774-1857). He developed the scale in 1805 to help sailors estimate the winds via visual observations. The scale starts with 0 and goes to a force of 12. The Beaufort scale is still used today to estimate wind strengths.
SPECIFICATIONS FOR USE ON LAND
Calm; smoke rises vertically.
Sailors stand around drinking tea.
Direction of wind shown by smoke drift, but not by wind vanes.
Very light and patchy: a Solo wins the race!
Wind felt on face; leaves rustle; ordinary vanes moved by wind.
A nice gentle racing wind.
Leaves and small twigs in constant motion; wind extends light flag.
A decent racing breeze: things are getting lively.
Raises dust and loose paper; small branches are moved.
Very lively, some capsizes.
Small trees in leaf begin to sway; crested wavelets form on inland waters.
Probably too much wind for novices unless using reefed Toppers. Much capsizing.
Large branches in motion; whistling heard in telegraph wires; umbrellas used with difficulty.
Many sailors stay ashore and watch the fun
Whole trees in motion; direction of wind shown by smoke drift, but not by wind vanes.
Only a few Lasers go out sailing
Breaks twigs off trees; generally impedes progress.
Only for the very experienced and foolhardy, and they soon regret it.
Slight structural damage occurs (chimney-pots and slates removed).
Sailors go and check that their boats and those next to them are well tied down.
Seldom experienced inland; trees uprooted; considerable structural damage occurs.
Sailors stay at home
Very rarely experienced; accompanied by wide-spread damage.
Club Committee organise emergency meeting to discuss new clubhouse roof. Boats blown over fences, rescue boats blown ashore.
Michael Fish was right: fortunately we don't get these in the UK.
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