THERE'S a clue in the name Langport; the town did indeed once have a port, even though it is situated more than a dozen miles from the sea – and could be renewing its maritime links in the not too distant future if climate change experts meeting in Copenhagen last week are right.

Scientists now believe that global warming will have far more profound consequences on sea levels than had previously been estimated – they are predicting that the planet's oceans will rise by more than a metre by the end of this century, rather than the half-metre increase they had been working on.

Not only will this have an acute significance for individual communities located at present-day sea levels, but entire areas of the South West peninsula will be in the firing line when it comes to widespread coastal flooding.

The national media habitually turns its focus on London, the Thames Basin and places like the Norfolk Broads in the east of the UK – but the increasing tides will have huge ramifications for the Westcountry, as is outlined in an official document which has been passed to the WMN.

"Climate is already changing – that much is certain," writes the Environment Agency's (EA) Kylie Russell, who is the organisation's climate change and energy officer in the Westcountry. "This will lead to rising sea levels and increased flooding. The South West region has a very long coastline and as such is extremely vulnerable to rising sea levels."

Suddenly even places like Langport, situated deep in the Somerset Levels, 12 miles inland from the nearest ocean wave, look worryingly vulnerable.

But not nearly as vulnerable as Bridgwater, located downstream on the banks of the tidal River Parrett. That town of just under 40,000 souls now looks to be the largest community in the region that is under direct threat from climate change. So much so that the chairman of a new body set up to regenerate the town is demanding a Thames-style barrage be built to protect it.

Bridgwater Challenge Project board chairman Anthony Gibson told the WMN: "The news from Copenhagen reinforces the need to protect Bridgwater and its 11,000 homes from flooding. At the moment this has been put at a 1-in-200-year risk – but the odds on it happening are shortening all time.

"You can give Bridgwater complete protection by building a mini surge barrier – and that would protect us at a cost of £40 million. This protection is an essential precondition for what the regeneration project is doing – a regeneration that could create thousands of new jobs in the town. But we need protection from the floods."

Meanwhile, perhaps ominously for Mr Gibson and the people of Bridgwater, the EA is overseeing a so-called "managed retreat" at Steart, out at the western mouth of the River Parrett.

Managed retreat is a polite way of bowing to inevitability. It's a way of saying: "Look at what happened to King Canute." And it occurs when there's a realisation that you can't beat nature, no matter how hard you try.

There will undoubtedly be a great deal in the way of managed retreat here in the Westcountry in the next 100 years.

"There are 14,700 properties in Devon and Cornwall that are currently known to be at flood risk from the sea," says Steve Marks, the EA's team leader for flood incident management in the region. "The numbers of properties at risk from flooding, inundation and erosion will increase due to the expected impacts of climate change.

"These impacts include sea-level rise, increased frequency and severity of storms causing storm surges (i.e. a higher sea level caused by a combination of low pressure and wind action), and waves generated by these storms.

"To put this into context, two of the most severe coastal flooding events in Devon and Cornwall occurred in October 2004 and March 2008 when a 0.5- 0.75 metre storm surge coincided with high (autumn and spring equinox) tides.

"Tides of this height could be normal with future predicted sea-level rise. When further exacerbated by storm surges of increased severity and frequency the impacts will be much higher," said Mr Marks.

To put that in modern parlance, we're in for a double-whammy. More ferocious storms occurring more often will help push the tides and waves even higher than the much-feared basic rise in sea levels.

That particular scenario is likely to be at its worst in Cornwall – the highly exposed county that juts furthest into the ocean. But other double-whammy events will hit other parts of the coast in our region. Take, for example, the massive landslides that have become a feature of the East Devon/West Dorset coast – they could become a lot more common in the future, according to the EA's coastal engineer in the area, Neil Watson.

"High levels of ground water can help cause these landslides and when you combine that with a higher wave action causing new erosive forces to bear along cliffs then you have an increased risk."

Mr Watson also talked of a possible inundation of West Dorset's famous Chesil Beach. "It has been breached before," he said. "There was a storm in 1824 when vessels were washed right over the top – and certainly increased storminess might be a thing that affects Chesil Beach more."

But, of course, it is in areas of human habitation most damage will occur. You only have to take a quick trip around the Westcountry coast to work out the at-risk areas.

West of the River Parrett and Somerset Levels you reach the West Somerset coastal plain from Blue Anchor to Minehead. It's reckoned that, a long time ago, waves used to lap the base of Dunster Castle's hill, now a mile inland – a metre tide rise would help them do so again. It would also turn a seaside holiday at Europe's largest holiday camp into an altogether different experience – Minehead's Butlins would be in the sea rather than beside it.

Further west, we come to the Taw and Torridge delta – a vast landscape of dunes and flatness stretching all the way upstream to Barnstaple. You will require a float-plane in order to land on Chivenor's airbase's runway in 100 years' time.

Along the north coast of Cornwall, EA engineers have worries about the Camel Estuary, where inundations could hit Padstow and Wadebridge. And west again there are concerns for the low- lying parts of the Hayle estuary basin.

But perhaps the most worrying place to live in 2100 will be in the once hugely desirable Isles of Scilly.

A one-metre sea rise would wipe out most of the archipelago's capital Hugh Town, half of which – including the main street – is built on a sand spit that connects the main island of St Mary's with the hill that houses the old Garrison. When you add increased storm surges and bigger waves to the rise in overall tides, the beautiful but low-lying archipelago looks very exposed indeed.

Back along the mainland's south coast, we come to Penzance and its neighbouring Marazion Marshes, at present protected by a low sea wall that could easily be breached by such tidal rises.

Out along the Lizard peninsula, the National Trust has already announced the future demise of Mullion Harbour, but there are also fears for Cornwall's largest freshwater lake. Loe Bar, the shingle ridge protecting Loe Pool, could easily be breached, so that one day Helston might again have a harbour just like it did centuries ago.

Tregony, high up the Fal estuary, is another ancient harbour town that hasn't seen a wave or a boat of any size for hundreds of years. By the end of this century, they might be considering building a marina there. Even Truro city centre, located in the same estuary system, could find itself looking more like Venice than anything built on Cornish granite.

Future developments in the Par area would be better adapted if they were to be built on stilts – and the same could be said for homes in various low-lying parts of the Tamar estuary. South Devon folk at present trying to protect the A379 road that traverses Slapton Sands will be regarded as brave but hopeless heroes in a century's time. By then, combers will be crashing into lower Slapton village, while the lagoon called The Ley and the village of Torcross will be but distant memories.

The Exe estuary will suffer a plethora of problems – not least caused by the possible disappearance of not one, but two, railways. Although, by 2100 it is likely that the Great Western line which continues around the coast to Dawlish and Teignmouth will be history. The tram line at Seaton will also have become another memory after the entire Axe estuary basin fills with salt water.

That's a basic round-up of what increased sea levels could mean to this region. In light of which, it's perhaps wise to reflect upon the words of Kylie Russell, who ends her report on climate change in the region thus: "We need to adapt our way of life so that we can be prepared for the inevitable and unavoidable effects of climate change."