Smithsonian has an article about nautical archaeology, focusing on Dunwich:
The sea that brought trade to Dunwich was not entirely benevolent. The town was losing ground as early as 1086 when the Domesday Book, a survey of all holdings in England, was published; between 1066 and 1086 more than half of Dunwich’s taxable farmland had washed away. Major storms in 1287, 1328, 1347, and 1740 swallowed up more land. By 1844, only 237 people lived in Dunwich. Today, less than half as many reside there in a handful of ruins on dry land.
Here’s Henry James on Dunwich, in English Hours (‘Old Suffolk’ — originally published in Harper's Weekly, 25 September, 1897), 1905:
If at low tide you walk on the shore, the cliffs, of little height, show you a defence picked as bare as a bone … [The land] stretched, within historic times, out into towns and promontories for which there is now no more to show than the empty eye-holes of a skull; and half the effect of the whole thing, half the secret of the impression, and what I may really call, I think, the source of the distinction, is this very visibility of the mutilation. Such at any rate is the case for a mind that can properly brood. There is a presence in what is missing — there is history in there being so little. It is so little, to-day, that every item of the handful counts.
The biggest items are of course the two ruins, the great church and its tall tower, now quite on the verge of the cliff, and the crumbled, ivied wall of the immense cincture of the Priory. These things have parted with almost every grace, but they still keep up the work that they have been engaged in for centuries and that cannot better be described than as the adding of mystery to mystery. … The mystery sounds for ever in the hard, straight tide, and hangs, through the long, still summer days and over the low, diked fields, in the soft, thick light. We play with it as with the answerless question, the question of the spirit and attitude, never again to be recovered, of the little city submerged. For it was a city, the main port of Suffolk, as even its poor relics show ; with a fleet of its own on the North Sea, and a big religious house on the hill. We wonder what were then the apparent conditions of security, and on what rough calculation a community could so build itself out to meet its fate. It keeps one easy company here to-day to think of the whole business as a magnificent mistake.
I’m keeping The Rings of Saturn for when we have a chance to go walking in Suffolk, but, via John Naughton, here’s Sebald on Dunwich:
The Dunwich of the present day is what remains of what was one of the most important ports of Europe in the Middle Ages. There were more than fifty churches, monasteries and convents, and hospitals here; there were shipyards and fortifications and a fisheries and merchant fleet of eighty vessels; and there were dozens of windmills … The parish churches of St James, St Leonard, St Martin, St Bartholomew, St Michael, St Patrick, St Mary, St John, St Peter, St Nicholas and St Felix, one after the other, toppled down the steadily-receding cliff-face and sank in the depths, along with the earth and stone of which the town had been built. All that survived, strange to say, were the walled well-shafts, which, for centuries, freed of what had once enclosed them, rose aloft like the chimney stacks of some subterranean smithy, as various chronicles report, until in due course these symbols of the vanished town also fell down.
Thinking about Dunwich and nautical archaeology made me read again about the project to use 3D seismic data to map the North Sea Palaeolandscapes — lands of hunter-gatherer communities, lost as water levels changed over 8000 years ago:
It's like finding another country. … At times this change would have been insidious and slow — but at times, it could have been terrifyingly fast. It would have been very traumatic for these people. … It would be a mistake to think that these people were unsophisticated or without culture. … they would have had names for the rivers and hills and spiritual associations - it would have been a catastrophic loss. … In 10,000 BC, hunter-gatherers were living on the land in the middle of the North Sea. By 6,000 BC, Britain was an island. The area we have mapped was wiped out in the space of 4,000 years. BBC News
From the project’s introduction:
The British continental shelf contains one of the most detailed and comprehensive records of the Late Quaternary and Holocene landscapes in Europe. This landscape is unique in that it was extensively populated by humans but was rapidly inundated during the Mesolithic as a consequence of rising sea levels as a result of rapid climate change. Previous researchers have recognised the rapid inundation may have preserved topographic features and caches of environmental data of high quality which may be used to provide insights into Holocene landscapes which, if located and sampled, may be unparalleled by terrestrial sites. Knowledge of the development of this landscape is also critical to our understanding of the impact of climate change on palaeobathymetry and shoreline sequences. It is clear that the exploitation of the Southern North Sea for energy and mineral resources, most notably aggregate extraction, remains a strategic goal for the UK and without adequate data this remarkable landscape is under significant threat from development. Furthermore, given that this landscape suffered changes comparable with those predicted for the British shoreline over the next century, the value in providing comparative data for the future impact of global warming seems clear.