Sea-levels, ‘climate change’ and the dilemma of local government

So often discussions of global warming and ‘climate change’ occur at the big-brushstroke level — how  the global temperature anomaly is faring, satellite measurements and so on. But the whole dispute can have a profound effect at the local level, especially when governments issue edicts about what people can and cannot do, because of the supposed catastrophe lying in wait for us.

A recent paper by Roche, Goodwin and McAneney brought this point home to me. Entitled ‘Management of the Coastal Zone in Byron Bay: The Neglect of Medium-term Considerations’, it sounds like the sort of paper that you glance over quickly. But it is a fascinating read, and you can get a copy here.

At the core of it is the AGW scare, extended into ever-rising sea-levels and the prospect of the destruction of coastal holiday houses and other property. Devastating storms do occur, and they can denude beaches of sand, chop out great chunks of sand-dune, destroy wharves and jetties, and cause houses to slide into the sea. And all this without any global warming at all. But were the seas to rise a metre or so, let alone the five metres forecast  by AGW Scaremonger-in-chief James Hansen, then such storms would plainly affect many more people and much more property.

Byron Bay is a pleasant holiday town on the North Coast of New South Wales, with the continent’s most easterly point at Cape Byron, and it has been identified as a beach ‘erosion hotspot’. It has had its share of storms and coastal erosion, and has been the site of some angry and expensive litigation, which all goes back to what governments decided to do.

The NSW Labor Government in power from 1995 to 2011, pursuing ideas that had been about for some time, fell for the precautionary principle, and decided that global warming was here to stay, the seas would rise, properties would go, and that the best plan was ‘planned retreat’ — that is, in the long run some land would disappear. If you were going to build, then you needed to build something that you could locate somewhere else when your land started to disappear into the sea. And local government bodies could decide where and what all that would be. Not only that, you couldn’t protect your house by building a sea wall, unless it was made of sandbags and was not more than 1.5 metres in height.

Needless to say, some property-owners found that the value of their land and buildings dropped at once and  alarmingly, and became irate. The NSW Opposition fought the election in 2011 partly on these issues, and when it was elected decided to overturn the planned-retreat strategy, and to allow property owners to protect their properties from the power of the seas if they wished to do so. Sounds better? Well, it leaves a lot of questions unanswered, and makes the job of local government no less difficult..

The authors make the fair point that what has happened is that one government went for the long-term strategy, while its replacement went for the short-term version. Neither seems to have considered what they call the ‘medium-term’ possibility. According to the Federal Government, between 157,000 and 247,000 existing residential buildings are thought to be at risk to a sea-level rise of 1.1 metres. Now no-one I know has suggested such a rise over this century, though it seems that the NSW Government had in mind a rise of 0.9 metres. The IPCC’s 4th Assessment report talked of a likely rise of between 18 and 59 centimetres, while current measurements seem to fluctuate between 1.7mm a year and around 3mm. Neither figure, multiplied by 100, seems to provide a scary outcome.

So on the face of it we have time to employ the medium-term solutions, which can be hard (rock walls) or soft (filling up beaches with new sand and stabilising dunes). The authors say this: ‘The key advantage of engineering solutions for the medium term is that they allow continued enjoyment of the coastline for another 30–50 years whilst preserving livelihoods and doing as little damage to the coast as possible. At some point, locations around the coast may well need to be abandoned as they become impractical and too expensive to protect, but in the authors’ minds it would appear that this time is not yet here.’

An underlying point is that coastal erosion is not simply a function of sea-level rise. Storms move sand around, and open and close lagoons and river mouths. The Shoalhaven River mouth was recently opened by a combination of heavy rain and storms, a rare occurrence; it is mostly closed, and indeed it was so when the first European to take up land there, Alexander Berry, arrived in 1829. I have seen the beaches around our coastal house change a great deal over the thirty-five years we have been on the South Coast, and earlier saw a great storm threaten several houses at Wamberal, on the Central Coast — and this was long before anyone talked about global warming.

To say it again,  scaremongering can have pernicious effects on small communities, as has plainly been the case in Byron Bay, where lots of money has been spent on litigation, and ‘the general public is at risk of losing its amenity in an iconic piece of coastline. Homeowners are at risk of losing homes, businesses their livelihood, and the government remains exposed to significant legal liability.’

We ought to be able to do better than this, and one has to reiterate that the climate models claimed to be able to foretell the future have never been validated. The website of Tamsin Edwards, about whom I wrote a couple of days ago, is called ‘All Models are are Wrong … but Some are Useful’. Climate models should not be used by governments as a basis for policies fifty years out, let alone for the kinds of tasks local government councils have.