Here comes the rain again

Perhaps we shouldn't be surprised. After all, Britons have come to expect wet weather, whatever the season. But though we love to moan, should we really just shut up and learn to love rain?

" I love the rain," says Woody Allen to his blind date in Play it Again, Sam. "It washes Memories off the Sidewalk of Life." His date stares at him with a kind of fascinated horror that anyone should want to sound such a prat. But we are all capable of moments of pretension or awe when confronted by rain, when watching the first element cascading out of the sky, as it seems to have done so relentlessly this summer.

At work in east London, I have watched, mesmerised, while what seemed like massed battalions of rainy militiamen have thrashed and pounded the window beside my desk, as if demanding entrance. At home I've seen a children's party turn into a Hitchcockian frenzy, as a cloudburst descended on 26 seven-year-olds in the garden; the tinies ran about, shoeless and sockless, exulting in being drenched, while the grown-ups yelled and gesticulated and tried to get them indoors. In the car, I've sat for what must be months, watching the windscreen wipers listlessly ushering the rain from right to left, sweeping it aside with a constant, two-note refrain of "Bugger – off – bugger – off," as if trying to dispatch a tenacious enemy. But I've also watched it falling with grey reluctance on the dismal roofs of Clapham and felt a kind of pity for the rain, for the desolation it engenders, and the misery in which it lives.

This is known as the pathetic fallacy, in which we impose on the neutral landscape the feelings we experience when looking at it. Look at those sorrowful hills. Look at that triumphant sunset. Look at this angry rain. Of all the available weathers with which we may try to empathise, rain is the most potent. It's the weather that's closest to us, that gets into our clothes and hair and shoes, that hugs us in its clammy embrace, that transforms the way we look, from stylish modern people into nondescript drowned rats. Outside non-earthquake zones, it has the most dramatic effect on the city streets. It makes country roads impassable, it swells rivers, dams and reservoirs to bursting point, as seen in this week's sudden flash-flooding, described as "monsoons". It ruins the cultural life of the nation. It interrupts the Tim Henman match, shuts down the test match for the afternoon, trashes the Commonwealth Games, sends patrons fleeing from the open-air theatre in Regent's Park and makes the nation's most benign and charming beach resorts look dismal and unloved.

The mood of the entire nation is affected by comparatively few things – royal deaths, royal jubilees, World Cup football, EastEnders, Big Brother, public transport, Stephen Byers – but precipitation from the sky is definitely one of them. Rainy June turned into sodden July, just as it did last year (remember Bill Clinton coming to the aid of Wimbledon tennis with some centre-court chitchat as the rain pelted down?), and the mini heatwave that got everyone excited and pink-cheeked is over, as August's arrival is heralded by storm clouds. You can feel the national nerve beginning to strain and twang. This is not just the syndrome called Seasonal Affective Disorder (or Sad) where you feel a little triste about the dark mornings of high summer. This is more like an affront to the national spirit. It's as though a contract exists between the British and the weather, one that says: we will put up with the crap conditions of soggy November and bleak December, frozen January and dismal, pointless February, on the understanding that we will get the woolly lambs and daffodils in April, the white and pink blossom in May, the sparkling meadows of June, and the heat haze in the garden in July. For the last five years, it has seemed that the contract has been broken – the weather has remained sullenly stuck on "February", and we're not sure we can take it any more. We can't take any more of the liquid stuff cascading down in high summer and lashing the skylight like a frenzied dominatrix.

Three things are currently giving rain a high profile. One is the awful weather itself. The second is the publication in September of Rain, a scientifico-cultural study of the stuff by the journalist Brian Cathcart, which explores why English hills and fields have always been awash (it's the Atlantic and the western mountains, pushing up the arriving clouds and then chilling them) and the effects of rain on the national psyche. The other is the half-century anniversary of the UK's greatest rain-related disaster, when a whole town was destroyed in a flood. Both the book and the anniversary ask questions about our British weather and our attempts to do something about it. And both illustrate our ambivalent desires to see rain as an enemy and a potent ally.

The sadists who presided over Japanese concentration camps understood the relentlessness of rain – how it dulls the spirit, how it comes down on you like bad karma. They invented the nasty water torture, in which a cup with a tiny hole in it is placed over your fixed-upright head, and drops of water drip down on your cranium until they feel like hammer blows. But poets and songwriters have been using the trope of weather-as-torture for decades. "I can't stand the rain," sang Anne Peebles in 1974, "against my window/ Bringing back sweet memories." "Here comes the rain again," sang Annie Lennox of Eurythmics, "Falling on my head like a memory/ Falling on my head like a new emotion." "Why does it always rain on me?" sang Fran Healy from Travis, petulantly. "Even when the sun is shining/ I can't avoid the lightning." To all of them, rain is an agent of the blues, the fateful Bad Stuff that will always land on you, no matter how much you try to avoid it. It's the perfect element for the tortured romantic – as anyone who's ever seen that photograph of James Dean walking, collar turned up, along the Boulevard of Broken Dreams, can attest. But you notice that rain isn't entirely negative – it brings back memories of good times with one's beloved, which are painful in a nostalgic sense.

To Woody Allen, as we've seen (however hammily), rain is a cleanser, a wiper-out of memories. Travis Bickle (played by Robert De Niro) in Taxi Driver was more sinister about it. "Thank God for the rain," he confides in his diary, "that helps to wash all the garbage and the trash off the sidewalk." As he drives through the night streets of "buggers, queens, fairies, dopers, junkies", he wishes, prophetically, that "someday a real rain will come and wash all the scum off the streets".

To many writers rain, especially the threat of a thunderstorm, represents a coming apocalypse. "The sky is darkening like a stain," wrote WH Auden in The Witnesses, on the eve of the Spanish Civil War, "Something is going to fall like rain/ And it won't be flowers." Bob Dylan's most apocalyptic song features a whole Book of Revelations cast of yammering talkers, burning innocents, dying poets and empty-handed villagers, all of them about to be swept away by a "hard rain". DH Lawrence was obsessed with water imagery, especially bursting banks and flooded dams, as metaphors for burgeoning sexuality. In LP Hartley's The Go-Between, the guests in the English country house spend most of the book wilting in the heat. Then, 30 pages from the end, "... the clouds had gathered again. This time they had an ominous look, white upon grey, grey upon black, and the still air presaged thunder." And you know poor Leo, the titular messenger, will be dragged through the climactic, purging rain by the scary Mrs Maudsley to find her daughter's secret trysting spot with her proletarian lover. To Portia in The Merchant of Venice, it's "the gentle rain from heaven" that falls on humanity like mercy. In the New Testament, St Matthew explains that God sends the sun to shine on the evil and the good, "and sendeth rain on the just and on the unjust", which doesn't help those in search of a moral quality in the weather.

Which brings us to the Lynmouth disaster. It was the hardest rain ever, the worst flash flood ever recorded. In the summer of 1952, rain fell like a vast sodden blanket all over the West Country. It went on for weeks. The dark turf of Exmoor was saturated. In north Devon, the rivers of East and West Lyn rose alarmingly after several consecutive days of thunderous rain. Measuring equipment at several places in the vicinity recorded 200mm of rain. Then on 15 August, an unprecedented nine inches of rain fell in 12 hours. The water flooded through the valleys in a torrent and finally crashed down – a 12ft wall of water – on the coastal town of Camelford, Lynmouth. Rocks and boulders were swept along with the torrent, wrecking buildings, bridges and the main street, and killing 34 people. The search for bodies went on for weeks.

As is usual with natural disasters, the stricken locals fruitlessly asked "why?", as if there might be some explanation, beyond nature, for such a tragedy. And for once there was, or appeared to be. Rumours began to circulate that the army was to blame. It seems that, in the days leading up to the floods, crop-spraying aircraft had been seen in the vicinity, apparently "seeding" the clouds with dry ice. This was a technique employed by government scientists at the start of the Cold War, by which they could make it rain to order by dropping powdered carbon dioxide or silver iodide on to a bank of cloud – the chemicals catalyse water droplets in a cloud and turn them into natural ice crystals, which enhance a cloud's ability to produce rain. Unbelievably, they were hoping to develop techniques for flooding enemy trenches in the event of a Russian invasion...

God only knows if the military was really responsible for the worst rain "attack" in living memory (although declassified government documents that were released in 1997 did admit that government planes had been seeding clouds in 1952). God knows how much global warming has contributed to our soggy state over the last five years. But our attitude to the rain remains a subtle and ambivalent one, in which we greet it as both an enemy and an ally, a cleansing principle and a implement of torture, an awesome spectacle and a dismal prospect. We sing about it with exultation, like Gene Kelly, and we sentimentalise it as the tears of heaven. But while Shakespeare gave Portia the line about the gentle mercy of the elements, his view of the weather was, I suspect, closer to the song that appears inKing Lear and, in a slightly different version, in Twelfth Night, with its bittersweet recognition that what comes out of the sky and what comes out of the human heart are sorrows that we're stuck with:

He that hath a little tiny wit,
With hey, ho, the wind and the rain,
Must make content with his fortunes fit,
For the rain it raineth every day.

Wet, wet, wet: the facts and figures of precipitation and our planet

By Julia Stuart

• Every minute of the day, one billion tons (907 million tonnes) of rain falls on the earth.
• If all the water in the atmosphere fell out as rain, it would cover the entire earth's surface with a puddle about 1.25cm (0.5in) deep.
• In terms of annual average rainfall, the driest recorded place on earth is the Atacama Desert in Chile, with just 0.1mm per year.
• In an average annual rainfall of 700mm (27.5in), the total impact energy of the raindrops hitting the ground can be the equivalent of as much as 4,000 tons of TNT.
• Five hundred million litres of rain can fall during the course of a single thunderstorm.
• The heaviest rainfall in one year in the UK is 6,528mm, recorded at Sprinkling Tarn, Cumbria, in 1954.
• The longest drought in this country occurred in Sussex and lasted 60 days between 17 March and 15 May 1893.
• In terms of annual average rainfall, the driest recorded place in the UK is St Osyth, Essex, with just 513mm per year.
• The US Geological Survey estimates that the earth has about 326 million cubic miles of water. This includes all of the water in the oceans, underground, and locked up as ice.
• Only about 3,100 cubic miles of this water is in the air, mostly as water vapour, but also as clouds or precipitation, at any one time.
• On Reunion Island in the Indian Ocean, 1,870mm of rain fell on 15 and 16 March 1952 – a record for 24 hours. At this rate, one hectare of land would receive 3,057 tonnes of rain.
• The record amount of rain in a year – 26,461mm – fell at Cherrapunji, Meghalaya, India, from 1860 to 1861. The world's wettest place on average is Mawsynram in the same state, where 11,873mm falls.
• Unionville, Maryland, USA, is on record for having experienced the greatest amount of rainfall in one minute (30mm).
• Only 3.5 per cent of the planet's total surface water is fresh, and most of that is frozen in the ice caps. A mere 0.01 per cent or so – one drop in every bucketful – is in a form suitable for direct human use: in streams, rivers, lakes and groundwater aquifers. And to make matters worse, well over half of this is inaccessible, or lost as flood water before it can be put to use.