When I wrote the The Rivers of Time after discovering that the river levels at Derby had been higher in the past and that this had influenced the town’s development, I was persuaded by the argument that man made global warming was raising temperatures to a higher level today than they had been at any time during the three and a half thousand years covered by my book, (Page 67 and 77). This means that sea levels today should be at previously unseen highs which should be affecting inland river levels. For this to be true I needed to explain how the river levels in and around Derby could have been higher during the Bronze Age, Roman period and Viking period than they are today because that is what the geological and archaeological evidence was telling me.
Not needing to consider higher temperatures causing higher water levels left me with the possibility that it was the land that was rising and “Crustal Motion” was the best fit for the jigsaw of facts I had accumulated, (Page 67; 68; 69; 70; 71; 76 and 82). There had been television documentaries discussing the rising of the land in the north of Scotland and the submersion of the land around the Solent. In addition Ireland is rising as a result of the “Rebound” from the ice sheets of the last Ice Age which is the action that “Crustal Motion” describes. Malin Head in County Donegal is rising at a rate of 2 to 3mm per year relative to sea level. I confidently thought that I had discovered the underlying mechanism for the disappearance of the ancient high water line in the Derwent and Trent floodplains.
The only real problem with an uplifting landscape was that the Roman Fort at Little Chester near Derby seemed to be too low relative to Ordnance Survey map contours when compared to the later water line indicated in the Anglo-Saxon Chronicles. To make the theory a better fit the fort site could have done with being a metre or two higher than it is. However, the scenario could be made to fit if consideration is given to the possible effects of a massive earth quake that struck Britain in the eleventh century and is graphically, but only briefly, described within the Chronicles. (This is examined on page 69 of my book).
“A.D. 1048.......This year also there was an earthquake, on the calends of May, in many places; at Worcester, at Wick, and at Derby, and elsewhere wide throughout England; with very great loss by disease of men and of cattle over all England; and the wild fire in Derbyshire and elsewhere did much harm”.
I was reasonably happy that the facts fitted together when I published my book but the doubts I did have are show by my inclusion of a paragraph titled “Possible Areas for Future Investigation”, (page 93). I now realise that important evidence for Derby’s development comes under the sub-heading concerning Climate Change, (Page 95). I was going to print in the last week of May 2006 when I wrote the following, not realising that it would become significant to my investigations:-
“A debate on BBC Television about Global Warming, (BBC 4, Wednesday 24th May 2006), informed me that during the years AD 800 to AD 1200 there was a ‘Medieval Warm Period’ which coincided with the expansion of the Vikings into other countries including Greenland. This warm period may have made the climate hotter than it is today so the subsequent rise in sea levels would also have been greater than those predicted in the near future should the atmosphere continue to warm up”.
This raised the possibility that the Roman Camp at Little Chester did see lowering water levels from the first century onwards to be followed by higher water levels as the Medieval Warm Period brought higher sea levels. A cycle of successive warm and cool periods over the last four millennia would also explain how it was possible for the Bronze Age Log Boat found near Derby to be afloat at the dry land location it was found at, (Page 54). The Medieval Warm Period could also explain why the sea gate at Harlech Castle in Wales is today high and dry above the present sea level, (page 94 and 95).
Even so, it still has to be remembered that crustal motion does exist and it is possible that the evidence I found represents the effects of climate change as well as crustal motion.
The real problem is the actual effect of the climate on sea levels during the Medieval Warm Period because if it was as substantial as my findings suggest then all of the rhetoric being bandied about by today‘s politicians is just “hot air”. (Pun intended).
The claim that carbon dioxide is increasing the “Green-house” effect and raising temperatures to a previously unseen level may not be accurate. If the water levels I found are correct then the Medieval Warm Period must have been greater than we are currently experiencing and may not be the result of the claimed “human” activity offered as the cause today.
I suspect that the purveyors of doom have mistaken the “Little Ice Age” that followed the Medieval Warm Period as some sort of ‘norm’ and these lower temperatures have influenced both their understanding of the earth’s natural temperature average and their interpretation of the current rise in temperature. It may be that the lower temperatures are the glitch and the rise in temperature is just the planet returning to its own ‘norm’.
Industrial pollution caused by man has risen steadily from the Iron Age with increasing activity in the medieval period and a rapid rise from the start of the modern era as represented by the introduction of machine power. Thomas Newcomen built the first self powered atmospheric engine in 1712 which heralded the birth of the steam age and the vast increase in the burning of fossil fuel which peaked in the 1950's. The massive increase in pollution caused by the Second World War with industrial outputs at a high and the release of CO2 by the bombing and burning should have led to high yearly average temperatures but instead we saw record winters, particularly 1946/1947.
If the band-wagon politicians have got it wrong and higher temperatures are the norm then, irrespective of all of their carbon trading and CO2 saving initiatives, the temperature will rise and the sea levels will follow leading to severe problems for vast numbers of people.
If Global Warming is natural then the politicians will not have planned for the many and varied effects of the eventual rise in temperature. Instead of concentrating on green house gases the climatologists should do some thorough investigations into sea and river levels during previous warm periods. If Global warming is a natural process then planning restrictions must be instituted on the historically vulnerable floodplains to prevent people suffering flooding and loss of property. The number of years that the floodplains will be inundated must also be established because, if my observations are correct, this could be centuries. Whilst on the subject of flooding I note that the medieval abbey at Tewksbury remained above the water line in the 2007 floods. Was this coincidence or was it built on an island during the period of water inundation described by my book? How else could the monks have known about the flood line unless they were witnesses to it?
It may be that our production of green-house gases are adding to a natural rise and we should seek alternatives but if it is a natural rise then our efforts will not prevent flooding, they will simply stop it being worse than it is going to be.
My research asks a number of questions that can be answered by investigation.
Is Harlech castle higher today than when it was when built or are sea levels lower?
If the sea levels at Harlech are lower today then it could be argued that the land has uplifted due to crustal motion and this, if translated across the country, will explain the difference in sea levels and the extensive silt deposits at Derby which is at the same latitude.
Do the silt banks of the River Derwent at Derby cover Roman remains at Little Chester?
Was the 3,600 year old log boat buried beneath silt from a later period?
However, if there is no evidence for crustal motion on this scale then the question has to be asked about Medieval Warm Period sea levels. If they were higher than today then the temperatures were also higher and if this is so it may be possible to carry out an archaeological investigation at Little Chester to see if there are Roman remains below the silt deposits. If there are remains then the silt was deposited after the Roman period and could well be evidence of higher water levels during the Medieval Warm Period.
A similar logic can be applied to the Bronze Age log boat and the dating of the silt deposits.
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