UPDATED 30 Sep 2010, 16:00
New graph comparing predictions from RSNZ and IPCC. Eye-opening!
The Royal Society of New Zealand just published a paper, Sea Level Rise – Emerging Issues. It reports new, more alarming predictions of sea level rise around New Zealand during the rest of the century. Or does it?
The paper warns us to expect the sea to rise several metres by 2100. Or does it?
Actually, it doesn’t and it doesn’t. We can all go home.
On a careful, sensible reading, the paper says very little but, by employing phrases such as “increasingly rapid melting”, “recent estimates of future rise are greater” and “global sea levels rose by around 120 metres”, among others, the casual reader gains the impression of dangerous rises to come. The story imparts grave concern.
But it’s all air kissing, candy floss and nonsense. They say nothing that would scare a butterfly. The only substantial statement in the entire paper is the very last one:
… the magnitude and rate of rise is poorly known, as is the way in which our coastline may respond [sic] these changes.
Which, I am sure you’ll agree, dear reader, is distinctly underwhelming. True it is, yet mild and unthreatening as the morning dew.
Search in vain for guidance
Elsewhere the paper drags us through such turgid passages as these (emphasis added to show the absence of anything worth saying or the saying of anything worth nothing):
Climate change may cause several metres of sea level rise over the next thousand years. For the decades and centuries that are important for planning purposes, we cannot yet state the likelihood of a given rate of sea level rise. However, our uncertainty is mostly one-sided, with more possible effects that might hasten sea level rise than might slow it.
New research has generated a range of projected rises that are considered reasonable, and rises considered plausible. Risk management is becoming important as a way of combining the range of potential future changes with the cost of their impacts and this provides a clear basis for taking account of the upper side of estimated ranges. This approach can allow for planning that does not lock in vulnerability, should an extreme scenario occur.
I pity a planner or civic leader combing this document for clues to a practical formulation of policy, for he searches in vain.
It tells us so little while saying so much. The paper tells us, by the figures in Table 2, that sea levels could rise from anywhere between 300 mm and 2200 mm, but Table 3 tells us that, “relevant to coastal planning” the range could be from 120 mm to 1900 mm.
“We don’t know what it will be, but we’re quite sure it will be bigger than we previously said. It’s worse than we thought!”
This is not a drill — they appear to be serious. So it could be small, or it might just be gigantic. Have these scientists made the slightest effort to refine their predictions for us? For there is something here for everyone. My daughter’s pregnant; I wonder will she have a kitten, a fox or an elephant?
Pity the student who emulates this paper
I wonder what fate would befall the Form 4 (year 10) science student who wraps his paper up in as many imponderables and unknowns (in other words, obscures the science he hasn’t done) as we see here yet attempts to provide practical guidance? Do these men have any idea how unhelpful their statements are?
Rather more pertinently, just how stupid do they think WE are?
I wondered what Professor Willem de Lange, Department of Earth and Ocean Sciences, University of Waikato, might think of all this, so I asked him.
The real risk to coastal properties
His response was, as usual, short and simple. He said the following and gave a list of probabilities:
To give some perspective, the following plot summarises the probability of experiencing different events with a magnitude of at least 1 metre over the next 90 years around the New Zealand coast. The corresponding values are:
Storm waves – 100%
Tsunami – 100%
Storm surge – 60%
Earthquake subsidence – 11%
Sea level rise – <<1%
This is the graph depicting the relative strengths of the various risks.
Dr Manning, the IPCC and the RSNZ paper all avoid saying what the probability might be of a sea level rise of 1 metre by 2100. But Willem is prepared to give an assessment. In his expert view, the likelihood is much, much less than 1 per cent.
To put that risk into perspective, the probability of a tsunami exceeding 10 metres striking New Zealand in the next 90 years is about 84%. Considering which one is more likely, which future threat worries you more: a tsunami or a global-warming-induced rise in sea level?
These assessed risks are all based on published information, apart from Willem’s opinion on the probability of extreme sea level rise caused by global warming.
These are the conclusions of the latest research. Our civic leaders should be preparing to protect us and our property from the most likely adverse events and on this informed assessment those most certainly do not include sea level rise.
They should promptly stop wasting our resources investigating climate change as a source of extra coastal hazards. Concentrate instead on the perils that are much more likely.
There is more material on sea levels rebutting the RS paper and Manning’s comments but this will do for now. It’s taken too long to get these comments published; let’s see the reaction to them.
UPDATE 30 Sep 2010, 16:00
A most helpful member of the NZ Climate Science Coalition (we shall call him Rupert) provided this graph superimposing the levels predicted by the Royal Society of NZ and the IPCC on the current rate of rise.
I’d be interested in your comments, but, simply put, I suggest it’s obvious that the RS have provided a bunch of maverick data points. They might have followed others in their predictions, rather than creating their own, but of course they take responsibility for the predictions as soon as they repeat them. It’s difficult to accept there is credible evidence for such outlandish projections.