here is a link for trade windsOriginally Posted by Azelor
http://www.britannica.com/EBchecked/...703/trade-wind
Its average speed is about 5 to 6 metres per second (11 to 13 miles per hour)
but can increase to speeds of 13 metres per second (30 miles per hour) or more.
Also this map is a gem on where the trade winds and currents combined are useful for shipping
http://web.deu.edu.tr/atiksu/toprak/den07.gif
and for the horse latitudes these are fine.
http://www.photographers1.com/Sailin...WindsLarge.png
It is also a worthy note for any game design that we also have seasons that change the layout of the routs. and several anomalies like el-nino, So if this was a game mechanism then I would roll 1d6 every year and on 6 there is el-nino, also if 1 is rolled then roll again but some variant effect are double.
http://www.weatherwest.com/wp-conten...pressureHR.jpg
have fun...
Here is also a good resource on sailing http://nabataea.net/sailing.html with a rout table where we can see what direction the wind is at what months.
from that page, for interest of our travel time theme is this passage:
The Monsoons
From an Arab perspective there are three basic monsoon winds. First of all, from April to June, the Kaws wind blows southwest. Later the Dammani SW monsoon blows from August to the middle of October. At this time, the monsoon changes direction, and the Azyab monsoon blows in a NE direction.
Most ships crossing the Indian Ocean planned to leave the east coast of Arabia during the second half of November and the first half of December. Ships leaving the Red Sea would start out the middle of October, so that they could catch the Ayab monsoon across the Indian Ocean, directly to the Malabar cost, reaching Kulam Mali during December. If they were moving on to China they would have to wait for the cyclones of the Azyab to die down in the Bay of Bengal before journeying on in January, crossing from Mulam Mali round the south of India to Kalah Bar in the Malay Peninsula. Arab ships usually did not venture farther than this, as Chinese junks brought their trade goods to the Malay Peninsula, and may to the island of Ceylon. (Sri Lanka) Once the Kaws winds started to blow, the Arab sailors would start for home, laden with their goods.
The chart below illustrates some of the sailing seasons that existed between India, Arabia and Africa. As local conditions such as land breezes would vary along the Arabian coast, the seasons were more complicated for the specific ports shown in the chart. Nevertheless the chart provides a broad outline.
From the table you will notice that the south-west monsoon strikes earlier further south, and lasts longer. As it moves northwards its duration shortens. Hence the Malabar coast of India is a dangerous place to be as early as May and remains so through September. This means that the sailing season in Malabar, India was only seven to eight months long. This affected the Indian vessels more than the Arab ones, for while the Indians must be all the way home before May, Arab vessels must only be clear of the Malabari waters before then. This allowed the Arabs more time to travel since they had a much longer sailing season when traveling from Arabia to India and back. This would help explain why the Arabs, who came from a land without abundant timber, dominated Indian Ocean trade routes for long periods.
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