Wet, wet, wet: What's with the weather today?

DREICH, dreary and depressing. Those three words sum up this Scottish summer more succinctly than any weather forecaster. The country's monsoon-like August has swept away not only our barbecues and picnic rugs, it has washed away our very notion of summer itself. In the past week, trains between Scotland's two major cities have been disrupted, roads have been closed and houses flooded as millions of gallons of rain have poured from the sky and pummelled Scotland into a flat squelchy morass. In some parts of the country more rain fell in two days than is normally seen in the entire month of August. From Caithness to the Borders, dozens of flood warnings have been issued, and Glasgow has become Venice by the grey bloated Clyde, experiencing its wettest 24 hours since records began.

We could forgive ourselves for asking some serious - if soggy - questions. Is our climate changing forever, as the environmentalist doomsayers predicted? Will the sunshine, only an occasional feature of our climate at the best of times, never be seen again in Scotland? Or is the recent bad weather just a blip?

The figures make for depressing reading: Scotland has experienced 15 per cent more rain and temperatures 16 per cent colder than average so far this summer, according to the Met Office. More rain fell in June and July this year than fell in the whole of 2003. It's good news for umbrella manufacturers, taxi drivers and cinema chains, but there's little to console the rest of us.

VisitScotland, whose job it is to lure tourists to these shores, feels compelled to warn potential visitors on its website that during the summer months "the weather at this time is, at best, unpredictable", pointing out that "the locals celebrate a single day of bright sunshine as 'glorious'". But for a country famed around the globe for its festivals, many of them held outdoors, including food and music events, Highland Games and the Edinburgh Tattoo, worsening weather isn't just inconvenient and irritating: it could be economically disastrous.

So is there any prospect that the weather is going to get better? "Erm, no," says Met Office forecaster John Hammond, before adding cheerily: "It's not getting worse, it just part of the natural variability we see in our weather. Scotland has very changeable weather - that is true historically - and it will continue to be so. The country's location, the coasts, hills and mountains and the wind coming in off the Atlantic Ocean all play their part in that." But he adds that it would be premature to throw away our shorts and sunglasses just yet.

The outlook looks bleaker if you talk to futurists. They study changes in climates across the globe to predict how they might impact on the way we live our lives. Futurist David Pearce Snyder says: "The weather will absolutely change the way we live, our infrastructure and the way we build our societies. In a country like Scotland which has experienced harsher winters and wetter, colder summers, we may see more people working from home, a system of mass transit will need to be developed to withstand extreme weather conditions and buildings, roads and bridges may all be designed differently."He points to the example of Valdivia in Chile, one of the wettest areas in the world, where many residents live in A-frame houses, with roofs sloping all the way to the ground, so that the water runs right off them. Snyder adds: "We are in the midst of enormous change and societies need to be resilient and adaptable."

If Snyder is right, it could be time for Scots to emigrate en masse. The alternative requires major changes to our nation's infrastructure and mindset. What would a Scotland that had permanently dug in against the weather look like? Will all of our sporting events and summer festivals have to be moved indoors? Could Glasgow or Aberdeen go the way of Montreal which boasts a maze of underground streets connecting offices, shops and homes? In the long, cold Montreal winters, where temperatures plummet below -20C, many residents live their entire lives below ground, slipping from heated cars to heated offices without ever feeling the chill wind on their face.

Ray Hammond, the author of The World In 2030, believes governments across the world should be preparing for long-term climate changes. "Changing weather patterns and the future unpredictability of our weather are among the biggest issues facing our societies. Governments as a whole aren't that well prepared, they need to invest more and be more proactive." He believes the financial implications could be huge. Along with a potential drop in tourism revenues, the Scottish Government could face a large bill for mopping up streets, damming rivers, drying out ruined houses, schools and shops, and redesigning our towns and cities to better cope with the changing weather.

But, says Ray Hammond, it's not a simple case of the country getting colder. "Extreme and unexpected weather will become the norm in future. We might find it gets much colder for a spell then much warmer - Scotland could have a heatwave next year and we'll be growing champagne grapes there," he adds. It might seem like an appealing prospect, but such wild fluctuations in temperature could have a detrimental effect on agriculture, infrastructure and even on our health.

DR CLARE Goodess, a senior researcher at the University of East Anglia's Climatic Research Unit, says it is too early to conclude that changes in the weather are the result of climate change. "If it continues for another decade then we might begin to wonder, but we can't draw conclusions on the basis of one or two summers. What we can say is that global warming leads to an increase in some types of extreme weather events like heatwaves, while, as a general rule, we'd expect there to be higher rainfall in some regions as a warmer atmosphere holds more moisture."It wasn't always like this. When that iconic Scottish family The Broons went for their annual holiday to the but'n'ben in the 1970s, the twins ended up with sunburn, not trench foot. You don't need to look back as far as the baking summer of 1976 to remember Augusts where it was possible to sit outside, remove your anorak and even risk barbecuing a sausage. Who can forget the glorious weather in 2003 and 2006? John Hammond, forecaster with the Met Office, blames unrealistic expectations: "We look back at summer through rose-tinted glasses and remember the good ones when it was really hot. That gives people the expectation of a prolonged period of dry, sunny weather that we don't always get."

Earlier this summer, BBC Scotland weather presenter Stav Danaos surprised Scots with a special report - backed up by Met Office statistics - which suggested that the weather in Scotland isn't actually any worse than it used to be. "When you look back at the statistics, since 1914, summers in Scotland have actually got drier, the temperature has increased slightly and the amount of sunshine has stayed around the same," says Danaos. "The last two winters have been harsh and we've had a cluster of bad summers so people feel cheated, but what we're seeing is just part of natural climatic variation, we get good years and bad years and we've had a run of bad ones." He points out that Scotland has lots of micro-climates which can distort the wider picture, suggesting that many of us have enjoyed brighter weather than we have.

Discussing the weather might be a favourite national pastime, but the lack of sun isn't just a good excuse for a moan. It could be damaging our health. Vitamin D is created naturally in the body through exposure to sunlight, but poor levels of light mean people in Scotland have a serious deficiency. Lack of vitamin D from sunlight is now implicated in health conditions from rickets to multiple sclerosis. In 1940, Glasgow Corporation handed out free cod liver oil and orange juice to schoolchildren to boost their vitamin D levels. In 2009, a proposal came before the Scottish Parliament to give schoolchildren vitamin D supplements. But the kind that comes in a bottle isn't as effective as that produced by the sun.

While we dream of a future in which the Scottish Government subsidises foreign holidays for vitamin D-deprived Scots, only time will tell what impact a long term change in the weather might have on net migration and on global tourism. Simon Calder, an expert in travel patterns, is optimistic, despite having been on holiday in Glasgow and Loch Lomond last week: "When the sun shines, Scotland is the most beautiful country on Earth. But I know from experience how clouds can cloak the place with gloom. However, travel is the industry of human happiness, based on optimism among travellers as well as those who work in the industry, and the nation will survive the present meteorological misery."As for this summer, is there the slightest glimmer of light on the horizon? "Yes, Sunday looks lovely everywhere. It could be 21C or 22C in some parts of the country. Monday is mostly bright, particularly in the East," says Danaos, before going on to spoil it all: "Tuesday starts off nice, but then there's rain."

Rain again? It's a sobering thought that in future, we could look back on the summer of 2011 as one of the dry ones…