Understandin wind direction for sailing purposes.
The force and essence of sailing is the wind.
It is the gear of a yacht, it is the thing which creates sailing as it is.
Without a basic understanding about direction, impact, apparent and true winds one cannot do much, and it is even dangerous to sail.
With time one can develop some kind of wind-intuition, the ability to predict what will happen, but one shoud never rely on this too much, because nature always put in their places people who have believed they are greater than it.
So - approach wind with a sense of reverence - it is your best friend and your strongest adversary. Always remember that when you set sails, you put your dear life into its hands.
Wind is caused by temperature differences. The basic principle is the following: air is warmed both by the ground and the sun. When it gets warmer, it becomes lighter and rises. Its place cannot stay a vacuum, as we have gas medium, so the adjacent cold wind takes its place, so we have a continuous flow.
It is very rare that there is no wind in coastal areas.
Wind Direction
The direction and speed of wind is always graphically displayed on visual weather forecasts. The wind blows along the isobars, keeping low pressure to the left and high pressure to the right. The most reliable way to check wind direction and speed before you launch the yacht is to consult an anemometer (wind speed indicator).
The first thing you have to understand about the wind is its direction - the wind is named after the direction from which it blows - so a wind blowing from south to north is a south wind. However, the wind direction is only in very rare cases steady (for example the trade winds in the Atlantic are steady) - so you need to be on the alert and always watch what the wind is doing. You should know what to watch, and you'd better don't neglect the signs the wind gives you. For example - waves are created by it, but only the white ripples on the surface show the wind direction. Other yachts at anchor or on mooring can give you clues - they float to point into the wind (unless in a case when there is a very strong current). Light and shallow boats prove to be the most reliable indicators. Beware - the sky is a trap! Do not look at it, because the movement of the high clouds have very little to do with the winds that determine what happens where you are. What you can do in advance is prepare the boat with your own indicators: you can adjust a flag or specially made windvane at the top of the mast. The so called the telltales are simple threads or audio tape - you should put them on the shrouds as high as possible. People who use cloth sails sew very flashy-coloured threads (like magenta, or red) to the sail. Others use cigarettes and orient themselves - but this is a very delicate skill, it is not accessible to anyone. There is one more subtle knack. Even the weakest draft makes up turbulence - so you will get different pressure on your two cheeks. You have to turn until the sound in your 2 years and the pressure on both cheeks is the same.
You will become good at that if you practise offboard sense to the wind - always when you are in the open, think about what is going on in the atmosphere around, and particularly what the behaviour of the wind is.
Wind is caused by temperature differences. The basic principle is the following: air is warmed both by the ground and the sun. When it gets warmer, it becomes lighter and rises. Its place cannot stay a vacuum, as we have gas medium, so the adjacent cold wind takes its place, so we have a continuous flow.
It is very rare that there is no wind in coastal areas.
Wind Direction
The direction and speed of wind is always graphically displayed on visual weather forecasts. The wind blows along the isobars, keeping low pressure to the left and high pressure to the right. The most reliable way to check wind direction and speed before you launch the yacht is to consult an anemometer (wind speed indicator).
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