ICOADS Web information page (Tuesday, 08-Nov-2005 23:57:33 UTC):

a)
b)

Fig. 3: COADS observations suggesting tracks used by sailing ships crossing the Indian Ocean in January 1855 (winter monsoon) and May 1856 (summer monsoon): a) Numbers of wind observations. b) The actual winds observed (the length of a 20 m s-1 wind arrow is shown below each map).

[Links to detailed][Durations of Indian ocean crossings]

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