OPINION: City’s sea-level plans don’t hold water
By Bob Carter
May 23, 2013, 10 p.m.
AROUND Australia, the Lake Macquarie City Council is among the most recalcitrant when it comes to paying attention to the science that underpins the global warming and rising sea-level issue.
The council appears to have learned nothing from the defeat of its former plans (based on utterly unrealistic science) to tamper in the property rights of more than 10,000 coastal properties by imposing section 149 certificates on them.
Nor has the attitude of councillors been chastened by the O’Farrell state government’s dumping of the former Labor government’s unrealistic coastal planning guidelines.
Instead, the council is now marshalling its powers again to force a Local Area (sea-level) Adaptation Plan on the communities of Marks Point and Belmont South.
Whilst adopting the trendy label of adaptation (which is most certainly the needed, cost-effective way of managing all Australia’s climate hazards), a reading of the allegedly new plan confirms that it simply represents a rebadged version of Lake Macquarie City Council’s previous interfering planning.
Do councillors really think that the public is so stupid that they cannot see through such an obvious ploy?
As many Newcastle and Lake Macquarie residents know, the bottom line is the measurement of what sea-level is actually doing, rather than computer projections about what it might do in the future.
The highest quality, long-record tide gauge on the central NSW coast – that at Port Denison, Sydney Harbour – records an average rate of sea-level rise of between 0.5millimetres and 0.9millimetres a year over the 20th century (as calculated, respectively, by Boretti and the National Tidal Centre). Even the larger of these two figures is low, being just half of the acknowledged global rate of rise of 1.8millimetres a year.
So far as is known publicly, the Lake Macquarie City Council is relying still upon the unrealistic coastal flooding maps that were prepared using their August 2008 figure of an assumed sea-level rise of 0.91metres by the year 2100. The flooding maps that were produced assuming one metre or more of sea-level rise by 2100, and which have been the basis for the public discussion since then, represent computer-generated virtual reality that has little to do with the likely 100-year-future real world.
Before attempting to impose any further coastal planning regulations regarding sea-level rise, the council needs to prepare flooding maps based upon the assumption of presumed rises of five, nine and 18centimetres out to 2100. These numbers represent the recent and 100-year-average rates of sea-level rise on the central NSW coast, and the 100-year average rate of global rise, respectively.
When these new and realistic flooding maps have been released and discussed publicly, then, and only then, will it be time for Lake Macquarie Council to reconsider its coastal planning policy.
Professor Bob Carter is a fellow at the Institute of Public Affairs and chief scientific adviser with the International Climate Science Coalition.