It is great to see some places taking sea level rise seriously.
This council in New South Wales has made a determination of sea level rise expected by 2100, and is hanging its policy-hat thereon.
"At its meeting of 27 January 2009, [Gosford City] Council considered and approved a report that recommends adopting, for purposes of future planning, a sea level rise planning level of 91cm by the year 2100."
The 91cm figure is made up of
59cm from the IPCC's AR4 global average sea level rise (ignoring ice melt) - high emissions scenario
20cm from AR4's allowance for ice melt uncertainty
12cm from the local CSIRO Technical Report (2007) – calculation for local variation on IPCC global average sea level rise.
The key uncertainty of course is the value for the 'ice melt uncertainty'.
Quite understandably the council is using the most solid data it can find, and that is the well-reviewed IPCC AR4 report. But as other postings have shown here, science and the ice has moved on quite a bit since 2007.
Thus I suggest that the council is doing well in that it is adopting figures that are very unlikely to be proven wrong (if we say that it will get at least as high as they say). They could have plugged for a higher figure (say +1.5 metres) without much chance of being wrong either, but they exercised admirable restraint by sticking to the IPCC values.
The national Real Estate and Insurance councils are of course panic-stricken by even this modest 91cm figure as it impacts directly on values and insurance costs.
The Property Council of Australia made a submission to the council including:-
"We have strongly advocated that the NSW Government demonstrate that it has considered and understands how sea level rise and the proposed projections will impact the property sector and broader community.
As an example, the Government must consider insurance implications and the likely response from the insurance sector as a result of revised sea level projections being released. This includes access to and the risk rating/cost of insurance.
A further worrying example relates to the values of property now caught within any area mapped as being at risk of inundation from rising sea levels. This will have severe flow on financial consequences for the and result in a reduction in lender’s loans to value ratio on property in this category."The property council's points are well made, but I think from the wrong direction. They would like to see the council adopt a lower sea level rise prediction so that the financial impacts will be avoided. They do not argue the science. They do not suggest that the 91cm is wrong, just that they do not want to accept the consequences of sea level rise at all. Therein lies a state of denial.
As far as I can discern the City Council's resolution of 27 January 2009 embodying a sea level rise of 91cm by 2010 still stands. Good on ya mates!