We spoke to the distinguished geographer and geomorphologist Andrew Goudie, a trustee of the Jurassic Coast Trust and Emeritus Professor in Geography at the University of Oxford. Professor Goudie is the former Master of St. Cross College, Oxford, and a past president of the International Association of Geomorphologists. He lives on Portland, but here he is at West Bay:

PROF. GOUDIE: Portland has a world class landscape. The view from the Portland Heights Hotel, or indeed from the prison, across Weymouth Bay, to the eastern Jurassic Coast — you can see Lulworth, and on a good day you can see all the way round to Dartmoor, around Lyme Bay. It must be one of the greatest views in the UK, to my mind.

Portland itself is remarkably undervalued. Visitors tend go to straight the Bill, which is perhaps not the nicest part of the island — though it’s not bad! People go there because they can park, and they’ve heard of Portland Bill, but there’s other bits of the island like Church Ope Cove and the whole northern part of the island, and the walk along the western side of the island, from Portland Heights right the way down to the Bill on that side — it’s all pretty spectacular.

Another place I love along the Jurassic Coast is West Bay, where you’ve got those fantastic cliffs of orange rock, and the beginnings of Chesil Beach. And then, when you look in the other direction, you can see round to Golden Cap and Thorncombe Beacon, that stretch of coastline is very spectacular. And hose little harbours like Seatown, Charmouth and Lyme, they’re all pretty fantastic.

And of course you’ve got all the wonderful fossil material, which is one of the main justifications for the World Heritage Site. It was where the great dinosaur fossils were first discovered and described; it’s where we got all the stratigraphy of the ammonites, and where paleobiology was developed. And you’ve got the whole gamut of fossils people can look at: from Swanage where you’ve got insect remains, through to huge dinosaurs.

The fossil record is not my particular area of interest — my serious research tends to be on geomorphology, but I’m interested in landscapes from a human and physical point of view. I’ve always tried to look at the human implications of the physical environment, and vice versa.

Portland is relatively lucky — in the sense that it’s not in an area that’s remotely industrial, and therefore it’s never really been exposed to a huge amount of locally produced acid rain. Of course, limestone is particularly susceptible to acid rain, but the gravestones in St George’s Churchyard are in pretty good nick, even though a lot of them are several hundred years old.

One thinks of Portland as a slab of Portland stone overlying Kimmeridge Clay — the slab floats down from the Verne at 500 feet all the way down to the Bill. But it’s not a simple slab: it’s actually folded by a few degrees here and there. So you have anticlines, which are raised-up strata, and synclines which are going-down strata, and that’s partly responsible for the shape of the island.

That slab of stone has been eaten into, at various times, by wave action — particularly on the western side, with the huge fetch that you’ve got: the huge distance the waves and swell come from, which eat away at it. It’s just a fragment of what must once have been there.

Because you’ve got this slab of limestones lying on top of the clays, it’s actually quite unstable. The whole island is surrounded by huge landslides, which you get your eye in for when you walk around both the East Weares and the West Weares. The whole area between Church Ope Cove and Southwell, and between Church Ope Cove and The Grove. It’s all a number of huge landslides dating back to the 18th Century, the 16th Century, the 11th Century. Rufus Castle has been attacked by landslides. And of course the pirates graveyard church, St Andrew’s, which was destroyed by landslides in the 17th and 18th Centuries.

In a lot of places what’s going to happen has already happened. But if sea level comes up then that may destabilize the coast, and it may, for example, mean — worst case scenario — that Chesil could be overtopped in a big storm. And, of course, we might get bigger storms in a warmer world, because there’s more energy around.

There was a huge flood event in the 1820s, which knocked most of Chesilton down — but now of course they’ve got the protection works, which they hope will stop that happening. But it remains a risk, and landslides are still going on. The footpath on the West Weares was closed a couple of years ago, and you can see a huge landslide there that’s happened in the last few years. It’s on ongoing problem, but I wouldn’t say the island was doomed! It’s always evolving.

I’m interested in the long term history of landscapes. Britain has been subjected to tectonic forces, albeit relatively mild, caused by the opening of the North Atlantic since the Cretaceous, and by the collision of Europe and Africa together, And you see that, of course, at Lulworth, where you’ve got that fantastic Lulworth Crumple as it’s known, at Stair Hole, just behind Lulworth Cove where the rocks are vertical or even over-vertical, caused by the shunting of Africa into Eurasia.

Prior to the Ice Age we had really rather hot conditions — near tropical environments — and we see relics of that dotted around Dorset, particularly the sarsen stones that you get at Portesham, the Valley of Stones, which are relics of tropical, relatively dry conditions, say 40-50 million years ago.

But it’s obviously the Ice Age that’s done so much to shape the landscape, because of the changes in sea level that it caused, and then we see raised beaches at Portland Bill, created 120,000 years ago or so. We see the flooding of the coastal landscape, and we’ve got the Fleet — we’ve got the rolling in of the sediment as sea levels rose after the Ice Age, giving us Chesil Beach itself. And we’ve got the old, dry valley systems which we see all over the Dorset chalklands — large, large valleys with no streams in today. I see all those sorts of long-term features in the landscape, which I find fascinating.

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