Yet again we’ve had a journalist in Ireland’s “Paper of Record” ventilating at the weekend about the widely-held belief that not only are world sea levels rising – which we all accept – but that these absolute sea level rises are happening twice as quickly in Dublin and Cork as they are elsewhere, which is hydrographic nonsense.
We also had a noted TV architect musing in print on how sensible it would be to “re-claim” land along Dublin’s secondary Tolka Estuary - presumably on its south side - in order to provide housing of a popular kind instead of the generally-loathed apartment blocks. This would thereby provide highly-desirable yet affordable family living beside the seaside.
In all, both pieces provided a fascinating insight into how words can be used in a secondary way to set the tone of any opinion piece. For instance, there’s the persistent bandying about of “re-claiming land from the sea”. That’s off target. Once upon a time, the world was all sea. So if we create new land, it’s infill, indeed it’s arguably theft against nature. But it’s certainly not “re-claiming”, even if that’s a difficult position to maintain when we’re up against the Biblical imperative of St John the Divine with his anticipatory Book of Revelations assertion that “there would be no more sea”.
MAINTAINING EXISTING WATERFRONT SUBURBS
Be that as it may, the idea of some infill along the south side of the Tolka Estuary is attractive, as it would be a completely new parcel of land which interferes with no-one else’s established seafront access. As it is, many of the schemes for infill in Dublin Bay have blithely claimed over many years that they would provide people with “new seaside homes”. But the proposed locations of these new homes would mean that some long-established waterfront suburbs are no longer beside the sea at all, which rather negates the good intentions of the basic projects.
A proposed infill for new housing along Dublin’s Tolka Estuary (right) might be acceptable if it were on the south side, thereby avoiding the sea access infringement of established waterfront suburbs in Clontarf. But it has to be remembered that the daily tidal draining of the extensive Clontarf Basin provides a useful scour-dredging effect for the entrance to Dublin Port via the River Liffey Photo: courtesy Dublin Port
But, that said, it has to be borne in mind that the twice daily exit of the tide from the currently extensive “Clontarf Basin” in the Tolka Estuary plays a significant role in the scouring of the entrance of the sea channel into the Liffey – in other words, it’s a freely available dredging process to facilitate the continuing and vital activity of our largest port.
The other point about the relative sea levels in Dublin and Cork has been allowed to pass unchallenged so many times that we wonder if anyone bothers to read these newspaper think pieces with any real attention at all. For sure, the global sea level at the Equator does come in a bit higher than on the rest of the planet, an effect of the world’s daily rotation. So I suppose we should be grateful that it doesn’t spin off the waters of the Pacific Ocean in their entirety into Outer Space. But it does mean that global sea level rising is a much more acute problem in low-lying Polynesian island nations.
SEA LEVEL IS AN ABSOLUTE IN IRELAND
However, within an island the size of Ireland, there is no significant difference between the absolute heights of the sea north and south, east and west. So when it’s recorded that the sea has risen globally by 70ml during the past 20 years, but that in Dublin and Cork tide recorders are showing a 20 year rise of 130ml, then it can only mean that Dublin and Cork have been quietly sinking by 60ml since 2002.
As has been demonstrated in recent years, Cork Harbour flooding is influenced by many factors, but this projection for 2050 is simply based on rising sea level.
The relative rise and fall of land masses is a geological and hydrographic fact. As the most recent ice age retreated to take away the ice-sheet weight from Ireland, some areas of land popped up almost visibly to gives us raised beaches and suchlike. And it’s reckoned that the geography of Greenland will need significant re-drawing as the weight of its enormous, many-miles-deep ice fields disappears - that is, if there’s anyone still around to take the necessary readings.
But meanwhile, in Ireland, we have to accept the implications of the fact that our Official Capital City and our Real Capital City are quietly going under. Knowing that it was the weight of ice which pushed down many parts of Ireland in times past, perhaps these modern localized tendencies could be blamed on the weight of self-importance in Dublin, and the weight of assumed superiority in Cork.
While admitting the vast civic and human problems which it would bring, rising sea levels in the Dublin area may provide some interesting opportunities – for instance, it might be useful to own the location of a potential fortress/customs station for the re-born Duchy of Howth beside the new watery frontier at Sutton Cross.
Whatever, it might help the debate and the planning in some way if it could be accepted that almost half of the relative sea level rise in Dublin and Cork is due to area subsidence, while the other half is due to absolute global sea level rises. Thus it really is time that we brought in Dutch experts to advise in Dublin and Cork on how best to deal with the fact that the apparent tide level in these cities is rising twice as quickly as anywhere else.
The Dutch approached the problem of most of their country being increasingly below sea levels by many means, not least in ensuring that they have the tallest population in all Europe. If we’re going to keep our heads above water in Cork and Dublin, a selective breeding programme should be introduced immediately to raise the national height. That said, having been with some of the grandsons at the weekend, I think it may have already been quietly under way for the past sixteen years. There’s evolution for you.
