What is it about the sun? When temperatures approach the mid-20s, it seems we all go slightly mad. Photos these past few days have shown beaches crammed with sunseekers, eager to roast themselves like potatoes. Editors could use the same pictures as last year, and the one before, because racing for the seaside, like lemmings for the cliff-edge, has become a national sport.

With Scotland enjoying temperatures almost as scorching as in the south, we’ve been warned “it’s going to get hotter”. As the Met Office issues extreme heat warnings for parts of England and Wales, and Northern Ireland hit its highest ever recorded temperature, it’s the promise some have been yearning for. Others brace themselves for a short spell of discomfort, to get through as best they can.

Cautious types like me, slathered in Factor 50, look as if we’ve been rolled in lard. At the opposite end of the spectrum, handling the heat turns into a macho contest, akin to walking on hot coals. The reckless and hardy vie for the deepest shade of terracotta, later peeling their flaking skin as if it were wallpaper.

Who could possibly begrudge anybody the pleasure of sunshine and warmth, when for so many months we endure the opposite? Yet in some respects, sizzling, record-breaking summers are turning up the heat in a deeper, more serious sense.

With endless days of baking warmth and little or no rainfall, water soon becomes a problem. Even this last winter and spring, when it seemed the tap in the sky had jammed full-on, we knew one day there’d be talk of looming drought. Hydrologically challenged minds such as mine find that difficult to compute, hence our carefree habits, whether it’s taking deep baths, running taps while we brush our teeth, or turning our lawns Hockney Green thanks to a sprinkler. Nor do we fathom why occasional torrential downpours are no solution. Somehow, we’ve got into the way of assuming that because our climate is uncommonly damp and wet, we need never worry about how much water we’re using.

On visits to Italy in recent years, it’s become clear how scarce water can get, even in a country with a healthy rainfall. Rome has had spells when water is strictly rationed, while at a friend’s in Tuscany, the shower barely coughs up enough to rinse off the suds in the morning.

Nor is this anything new. The plot of John Mortimer’s 1988 novel, Summer’s Lease, revolved around Brits staying in a Tuscan villa, where the pipes run dry. In that instance, things escalated to murderous levels, but even though in a normal Italian summer there’s just enough water to get by, you sense the day is coming when people will be wishing they could turn wine into water.

How peculiar it sounds, urging caution, while Germany and Belgium reel after devastating floods. Yet their calamity is inextricably linked with increasingly frequent droughts worldwide. The rain storms that caused rivers to rise and dams to burst are all part of the same haywire climate cycle that is causing catastrophic droughts elsewhere. By comparison with what California is experiencing right now, Scotland’s shrinking reservoirs look like the Pacific Ocean. Yet even here there’s no room for complacency.

As wildfires continue to rip through British Columbia, following temperatures more suitable for a smelter’s furnace, and Oregon fights to bring its worst-ever bushfires under control, the seriousness of excessive heat becomes all too obvious.

Likewise in Australia, where no year now seems to pass without nightmarish bushfires, trapping communities and wildlife in the flames. Despite this, I got into a conversation with a deluded Australian not long ago, who insisted climate change is a myth. It was what you might politely call a rather heated exchange.

In California, meanwhile, farmers are ripping out vast orchards of almond trees, for lack of water to cultivate them. Under searing conditions, their fields are scorched, completely inhospitable to any crop that requires a regular drink. Since a single almond requires 12 litres of water to grow, the millennial almond milk craze has fuelled one of the most environmentally hostile products on the supermarket shelf. After this summer, I suspect its days are numbered.

Almonds aren’t the only problem. For decades, California has defied geography and climate by pumping billions of gallons of water into orange groves as well as places, such as Las Vegas – the definition of meretriciousness – that should by rights have remained virtual desert.

How long that pipeline can be sustained is anybody’s guess, but in light of an unmistakable trend towards more volatile and uncontrollable weather extremes, the Sunshine State is becoming a new frontier in the fight for water, the most precious of natural resources.

Novelists have long predicted that future wars will not be about oil or land but water. Now, the stuff of fiction is turning into reality, and coming a little too close for comfort. Whether it’s floods in Germany or bushfires in New South Wales, we can no longer live as if the world’s resources, or lack of them, is somebody else’s problem.

There’s not much we can individually do to improve conditions elsewhere, other than avoid buying water-hogging goods, but within our own borders some of the solution lies with us. We have always had occasional hot, dry summers, where tarmac bubbles and trains are cancelled because of buckled tracks.

Only in recent decades, though, have we grown so heavily dependent on water that our use of it could be called profligate. If we had to carry buckets from a well, as in the past, we would treat it with more respect. As it is, for many of us there’s barely a day when the dishwasher or washing machine go unused or, in this heat wave, we don’t hose the garden.

As recent headlines make clear, we can’t afford to take things for granted. We must dial down on our consumption, and not just in exceptional summers. When television news presenters turn to the weather forecasters, it’s usually in hope of sunshine and heat. Perhaps we need to adjust our mental barometers. Recognising that stormy conditions lie ahead, it’s time for all hands to the pump.

Our columns are a platform for writers to express their opinions. They do not necessarily represent the views of the Herald.