The wind, as we know, is simply air in motion. If the air is still or stagnant we have a calm - but in Ireland it is very rarely so.
And when the wind blows strongly we are charmed or inconvenienced by what it does to us, rather than experiencing any intellectual curiosity about its cause.
Our feeling might be summed up by John Masefield's little ditty: A very queer thing is the wind/I don't know how it beginned/And nobody knows where it goes/It is wind, it beginned, and it blows.
The air moves to provide a breeze because of variations of atmospheric pressure over the Earth's surface. Intuitively, one would expect the air to migrate directly from high pressure to low pressure, and indeed it would if the Earth did not revolve.
However, as Galileo said, Eppur si muove, "But it does move", and the complex forces introduced by this rotation cause air to blow along the isobars, the lines joining points of equal pressure on a weather map. 'This relationship allows the forecaster to estimate tomorrow's likely wind.
The starting point for Irish wind forecasts is the current pressure pattern over the North Atlantic, where the isobars identify the locations of the depressions and the anticyclones.
The first predictive step, often done by means of a computer, is to calculate how this pattern will look tomorrow, to estimate where the different pressure systems may have moved to, and how the isobars may have arranged themselves by then.
The winds to be forecast for tomorrow will correspond to this predicted pressure pattern.
The wind will be inversely proportional to the distance apart of the isobars: the closer together they are, the stronger the wind will be.
But there are further complications. The relationship between the wind and the isobars also varies with latitude; a given spacing of the isobars gives a stronger wind at, say, 30 degrees north latitude than at 60 degrees.
The practical solution for the forecaster is to use a geostrophic scale, a special diagram constructed for the type of chart in use which shows, in a series of curved lines, the appropriate wind at each latitude for a given distance apart of the isobars.
The forecaster can use a pair of dividers to measure the perpendicular distance between two adjacent isobars, note the latitude, and then read the corresponding wind speed from the geostrophic scale.
But nowadays, of course, they let the computer do it for them.