It is a tedious truism of business system design, repeated far too often, that information has no purpose if it doesn’t change what you do. There’s no point in capturing data just for the sake of it, or in designing intricate reports that do no more that satisfy curiosity.

But that’s no way to live the rest of your life, I suppose. Much of what we read or watch might influence what we think, even if it has no effect on what we do. Sometimes it’s not even about thought. Comedy and music are often merely entertainment. They change how we feel, but not what we think or do. Dull is the man or woman for whom every moment of life must be useful.

That said, what about the weather? I was watching the Andrew Marr Show (a chattery political review shown live on BBC 1 every Sunday morning at 9) when, after the customary banter, the great British-Polish meteorologist Tomasz Schafernaker presented a three- or four-minute weather forecast (presumably as Andrew Marr’s interviewees hastily swapped chairs and the British nation poured itself another cup of tea) and it struck me that I can’t remember a single occasion when the weather forecast has made the slightest difference to what I do.

Homo Sapiens has probably been discussing the weather for hundreds of thousands of years. Recent findings near Lascaux in France, site of some of the most intriguing and beautiful Palaeolithic cave paintings in the world, suggest that the weather preoccupied our ancestors as much as it preoccupies us. Emerging from the cave each morning, our ancestors no doubt swapped cheery thoughts on the weather as lightly as we do:

‘Exceptionally warm weather for the time of year, don’t you think, Mrs Ngnmnbhurtyghfy.’

But recently discovered paintings suggest it went much further than that. Placed near the entrance to some of the valley’s smaller caves, caves that probably served a domestic rather than ceremonial function, there appear to be a range of weather conditions roughly shown adjacent to each other in a panel (towering clouds, puddles, the sun partially occluded or at full strength, trees bending in the wind, bison sheltering under rocks) using symbols that are uncannily like the symbols placed on the conventional TV weather map. Experts are divided as to their purpose, but a consensus has emerged that they are evidence of early meteorology. Ignorant of the idea of a ‘cold front’ or ‘warm front’ the Tomasz Schafernaker of the day, probably fulfilling a religious as well as a forecasting role in the community, could mark the symbol or symbols that most obviously reflected the weather conditions he foresaw.

For those living in the damp near-outdoors some inkling of the weather might surely have affected the daily routine (when to sow and when to reap, when to stay at home and make myths, or, indeed, when to talk about the weather).

But in the modern world, and for most of us the weather is an irrelevance. I don’t possess different clothes or shoes for different kinds of weather and I am incapable of keeping hold of an umbrella for more than a day or two. I do not have a seasonal wardrobe or clothes for different weather conditions. I wear a winter jacket until March 11th, and then a lighter one until May 22nd. | reverse the sequence in the autumn. It makes no difference to me if it’s raining, though I might call a taxi if the rain is heavy, a fact I determine not from the television or radio, but by looking out of the window.

In acknowledgement of the utter pointlessness of the weather, TV Nova, one of the commercial television stations that emerged in the early 1990s in the post-communist Czech Republic, made their weather forecasters go topless. Well, they began topless, apparently, and then put on whatever clothes were appropriate for the weather to come. Perhaps, on some occasions, only sunscreen.

Rather in that tradition, the surprising Mr Schafernaker recently posed topless for Active magazine: