The Eurobodalla Shire Council (ESC), of which I am a ratepayer, has written to me letting me know that I might be contacted soon as part of a community outreach survey. The Council wants to ask for a special rate increase to fund new infrastructure projects, and needs to know what we ratepayers think, because ‘your rates are the Council’s main source of income’. Council has helpfully provided information about what it proposes to do if the increased rates are provided. They seem fine to me.
Nothing in the information talks about sea-level rise, but ESC and the adjoining Shoalhaven City Council are also worrying about what to do with the IPCC forecast of large rises in sea-level over the remainder of the century and beyond, and have commissioned a report from a consultant, in this case Whitehead and Associates, which you can download from here.
Whitehead and Associates, according to its website, operates in the fields of on-site and decentralised wastewater management, soil and water management, waste and landfill management and environmental geology. It has done a deal of work of that kind. For this job it took on as partner Coastal Environment Pty Ltd, which describes itself as a specialist coastal, estuarine and port engineering consultancy built around the experience and expertise of the principal of the company…
Now since our own property in Eurobodalla Shire, though adjacent to the sea, is also some thirty metres above it, we have no immediate anxiety. But since I have an interest in this much-debated issue, I thought I would read the consultants’ report and see what I thought. It didn’t take me long to become somewhat alarmed.
While the Disclaimer says in part that Limits to understanding climate change science, predicting future emissions and projecting future sea-level rise, mean that there is significant uncertainty and absolute predictions cannot be reliably made, the rest of the Report seems to have forgotten that caveat entirely.
The experts go quickly to the IPCC’s AR5 and pronounce as follows (emphasis in the original): Having reviewed the IPCC’s AR5 report, we have found it to provide a balanced representation of the present state of the science, including discussions relating to uncertainty and possible errors in assessment. We consider that the modelled projections from the IPCC’s AR5 report are ‘widely accepted by competent scientific opinion’ … [and] form a suitable basis for deriving local projections of relevance to the study area.
Oh my goodness! Just as these days everyone needs a medical advocate to speak for them to nurses, doctors and hospitals, when hospital is where they are going, local government councils need some kind of disinterested research advocate to help them deal with advice like this. Does anyone on ESC know, for example, that these modelled projections have little validity, that the models themselves have never been verified or validated, and that where models have tried to predict temperature they have overstated the real outcome again and again? Why would you use them for sea-levels?
It gets worse. The consultants have decided to recommend the IPCC’s Representative Concentration Path (RCP) 8.5 projection, which assumes an astonishingly large accumulation of CO2 in the atmosphere by the end of the century, and provides (after their analysis of current sea levels, which seem very high to me) nearly a metre increase in sea levels on the South Coast by 2100, and half a metre by 2070. What is the probability of such increases occurring? On the observational evidence so far, a very small probability indeed.
Fortunately, another set of experts has stepped in to help the two Councils, and you can read their account here. I know the leader author, Professor Bob Carter, and have a high opinion of his technical skill and his common sense. He is a palaeontologist with an international standing. Several of the other authors I know by reputation, and some are experts about sea-levels here and around the world. Their report has been offered as friendly advice to the Councils, by those who read the other report and thought it was so wrong that it ought not to be followed in policy-making.
They too see the IPCC Report as the wrong basis for policy: no effective coastal management plan can rest upon speculative computer projections regarding an idealised future global sea-level, such as those provided by the … IPCC. Coastal management must instead rest upon accurate knowledge of local geological, meteorological and oceanographical conditions, including, amongst other things, changes in local relative sea level.
The last is a most important point. Average global sea levels don’t mean much when you are talking about a specific location. Coastal areas can be sinking or rising because of geological changes, and these changes can be much more significant than changes brought about in the volume of the oceans. As it happens, the South Coast of NSW is geologically pretty stable, while the annual rate of sea-level increase at Fort Denison in Sydney, not so far away, has been tiny — about 1mm or less since the 1880s. Some recent studies suggest that the rate is decreasing.
The Whitehead and Associates Report says the average annual rise is 3.3 mm, which is larger than any figure I have recently come across for sea-level rise in the past twenty years. Carter et al say that the consultants have done this by considering only very recent Fort Denison data, processing the data in an unexplained way and relying on models, not on actual data.
The NSW Chief Scientist advised Councils some time ago that they should use the closest available long-term tide-gauge measurements when they were formulating policies on coastal management. Carter et al conclude that the likely 7.3cm rise [not a metre!]in local sea level in NSW over the next 100 years is too small to justify a major planning response.
Speaking as a financially disinterested ratepayer, I strongly agree, and suggest to the ESC that it file the Whitehead and Associates Report in a bottom drawer somewhere, and get on with the infrastructure projects that it wants the rate increase for.