On 29 March Emeritus Professor Cliff Ollier had an article published on sea levels in The Australian entitled “CSIRO’s Alarmism More Dangerous Than CO2” (see below). Ollier argued that “the CSIRO projection (of sea levels) is extreme” and “uses figures far in excess of even the IPCC”.
The response by the head of CSIRO’s Marine and Atmospheric Research is yet another example of the politicisation of CSIRO and its failure to portray scientific conclusions about the future as having wide uncertainties. The head in Hobart claims that trends over the last 20 years or so have “been substantially higher than the 1.7mm a year average rise in the 20th century” and that estimation of future levels “also depends on how the dynamic processes of the climate system will shape them” (see letter below). But he says nothing about either what the “dynamic processes” might be or what was the higher rate of increase in the last 20 years.
My letter below points out that, over the last century of rising temperatures, the sea level rose by between 20-30cm and the same rate of increase has continued in recent years. In fact, the average increase since 1992 (when satellite measurement has been used) has been 3.2mm a year, but falling to 2.2 mm a year between 2002-2010.
What the CSIRO head failed to mention is that even if the average increase returned now to 3.2mm a year, that would still result in sea levels being less than 30 cm higher in 2100. This compares with the IPCC projected range of 19-59cms and would provide ample opportunity for Australia and most other parts of the world to take measures to prevent serious damage from such an increase. In short, and using IPCC type language, it is highly unlikely that global warming will constitute a serious sea level problem.
Our CSIRO politicians may well argue that increases in temperatures in the range now being canvassed in the recent joint CSIRO/BOM report will create an environment in which sea levels will rise faster because of ice meltings. But the report provides no supporting argument for the temperature projection that has now been adopted by these science politicians - it is for an increase of 1.0 to 5.0 degrees by 2070 compared with the projection by the IPCC in its 2007 report of 1.0 to 4.0 degrees to 2100. This higher projection is the more astonishing given that there has been no statistically significant increase in temperatures since 1998.
The CSIRO head also failed to mention that the higher rate of increase in sea levels in the north and west of Australia, mentioned in his letter, may be partly due to a lowering of land levels under the India ocean ie nothing to do with climate change per se. In the Pacific ocean there appears to have been no increase in sea levels since 2002.
The serious immediate problem arising from the CSIRO’s purported scientific projections is that they are being used by local councils to restrict coastal property development, with serious adverse effects on property values. State governments should now advise local councils of the faulty analyses by the CSIRO and instruct them to effect a major easing in their restrictions on property development in coastal areas. At the forthcoming meeting of COAG, they should also inform Commonwealth Ministers that they have ceased to have confidence in CSIRO analyses.
Des Moore
Letters on Sea Levels Published in
The Australian, 31 March 2012
Devil in the detail about the deep, blue sea
CLIFF Ollier makes several claims that misrespresent CSIRO's position on sea-level rise ("CSIRO alarmism more dangerous than CO2 , 29/3).
For example, he suggests that sea-level rise by 2100 is based on a simple extension of recent trends in observations. The estimation of future sea level does require consideration of those trends but also depends on how the dynamic processes of the climate system will shape them. Those processes are expected to accelerate sea-level rise and some acceleration is evident in observations from recent decades.
Further, the Intergovernmental Panel on Climate Change does not subject data to modelling, as Ollier suggests, but reports climate modelling and analyses done by scientific institutions around the world, including the CSIRO, that have been scrutinised by the peer review system in the scientific literature.
Global sea-level trends in the 20th century were around 1.7mm a year, as Ollier acknowledges, but trends over the last 20 years or so have been substantially higher than that, including around parts of Australia. This is especially so to the north and west of Australia where trends of up to 8-9mm a year have been recorded.
It is true that projections of future sea level come with some uncertainty, as does any projection of the future. The range of values for future sea-level rise, however, are tested thoroughly by science against the best available knowledge. This scientific rigour is important to ensure we can make choices about how to prepare for the future.
Bruce Mapstone, chief, CSIRO Marine and Atmospheric Research, Hobart, Tas
CLIFF Ollier points out that the CSIRO has adopted predictions of sea levels that assume future trends that are way above recent ones as well as those in the 2007 IPCC report.
The reality is that there is no scientific basis for predicting that by 2100 sea levels could be 59cm higher (IPCC maximum) let alone the 90cm adopted for NSW coastal areas.
The only prediction that has any logic is one based on what has happened during the last century of rising temperatures. That has resulted in an increase of between 20-30cm. This happens to be the average rate of increase in recent years.
Des Moore, South Yarra, Vic
BUSYBODY councils deploying shoddy science to destroy seaside land values were properly trounced by Cliff Ollier. With expert authority, he questions the CSIRO's projection on which such policies are based.
Ollier backs a 2009 opinion from the National Tidal Centre when he writes: "This is a reasonable level accepted by most sea-level watchers outside the IPCC and CSIRO and gives a sea-level rise of about 15cm by 2100". [He said] the "upper end was 3mm a year", which gives a 27cm rise by 2100.
He also notes declining estimates of sea-level rises in successive IPCC reports right down to 59cm in 2007.
The December 23 issue of Science reports on a meeting of the American Geophysical Union and notes criticism of the IPCC's 2007 projection of only a 25cm sea-level rise by 2100 from ice-sheet losses. It then reports a polling of 28 glaciologists that came up with a mean estimate of 32cm. Adding to that collective expert judgment of all other causes of sea-level rise the total was 61 to 75cm.
James Guest, East Melbourne, Vic
FULL marks to Cliff Ollier for giving us the example of The Netherlands as a nation that knows how to deal with sea-level rises. With a determination to preserve their land and their people from the threat of imminent inundation, rather than a hypothetical risk in 100 years' time, the Dutch began building dykes 2000 years ago.
If they'd taken the attitude of the Port Macquarie-Hastings Council, they would have spent the last two millenia crowding into an ever-decreasing space.
Dave Kirkham, Frenchs Forest, NSW
CSIRO Alarmism More Dangerous Than CO2
article published in The Australian, 29 March 2012
Drastic remedies for extreme sea level projections can’t be justified
The Weekend Australian reported on March 24 that Port Macquarie Hastings Council was recommending the enforcement of a "planned retreat" because of an alleged danger from sea level rise in the (distant) future.
The controversy has two main aspects: is the alarming rise in sea level projected by CSIRO reliable? And is moving people from near-shore sites the correct response?
The CSIRO projection is extreme, but before explaining why, I would like to note that the world’s main source of alarmism is the Intergovernmental Panel on Climate Change. This is not really a scientific body but one that adjusts data and subjects it to mathematical modelling before passing its ‘projections’ on to politicians.
The CSIRO and Bureau of Meteorology, then further adjust data and produce more models with even more extreme scenarios.
In the Weekend Australian of November 7, 2009, the director of the National Tide Centre of the BOM, Bill Mitchell, reported an Australian average sea-level rise of 1.7 mm a year. This is a reasonable level accepted by most sea-level watchers outside IPCC and CSIRO and gives a sea level rise of about 15 cm by 2100. He said the “upper end was 3 mm a year”, which gives a 27 cm rise by 2100.
At 8.30 am on November 18, 2009, ABC Radio National had a program on sea level changes. National Sea Change Taskforce executive director Alan Stokes said: “The IPCC estimate of rise to 2100 was up to 80 cm.” No new data was provided to explain the leap and, in fact, the worst estimate of IPCC in its last report was 59 cm.
Note that the IPCC estimates have been falling with each report. In its second assessment report the high-end projection of sea level rise to 2100 was 92cm, in the third assessment report 88 cm, and the fourth 59 cm. It is good for the reader to look at sea level measurements. You can see the sea level data for the United States and a few other countries at http:/tides and currents.nooa.gov/sltrends/sltrends.shtml. Most stations show a rise of sea level of about 2 mm per year, but note the considerable variation even within a single state, though these are no cause for alarm.
The CSIRO uses figures far in excess of even the IPCC, which until now were the greatest alarmists. In its 2012 report, State of the Climate, CSIRO says that since 1993 sea level has risen up to 10 mm per year in the north and west. That means that some place has had a 19 cm rise in sea level since 1993. Where is this place? The European satellite says that sea level has been constant for the last eight years.
How does the CSIRO arrive at its figures? Not from new data, but by modelling. Models depend on what is put into them. For example a 2009 report, The Effect of Climate Change on Extreme Sea Levels in Port Phillip Bay, by the CSIRO for the Victorian Government’s Future Coasts Program based its model on temperature projections to 2100 of up to 6.4 degrees. That is the most extreme, fuel intensive scenario of the IPCC and implies unbelievable CO2 concentration levels in 2100 of approximately 1550 parts per million.
Usage of all known fossil fuel reserves would only achieve half of this and continuation of the current rate of increase in concentration levels would result in only 550 ppm by 2100. The result is a CSIRO prediction of sea level rise for Port Phillip Bay by 2100 of 82 cm and, with the help of the BOM, a further increase due to wind to 98 cm. That is well above even the top level projected by the latest IPCC report.
This example is from Victoria but sea levels must have roughly the same rises and falls all over the world. So the whole world should be alarmed, not just NSW. Indeed, the IPCC and CSIRO try to alarm the world with stories of drowning of low islands, like Tuvalu. But detailed mapping has shown that Tuvalu, and many other coral islands, have actually grown over the past twenty years.
The Netherlands is particularly vulnerable to any large rise of sea level. It is also a world leader in coastal science and engineering, and the Dutch are not alarmed. In the December 11, 2008, issue of NRC/Handelsblad (Rotterdam’s counterpart to The Australian) Wilco Hazeleger, a senior scientist in the global climate research group at the Royal Netherlands Meteorological Institute wrote:
“In the past century the sea level has risen 20 cm. There is no evidence for accelerated sea-level rise. It is my opinion that there is no need for drastic measures. Fortunately, the time rate of climate change is slow compared to the life span of the defense structures along our coast. There is enough time for adaptation”.
This brings us to the second part of the debate. We should adapt to changes in the shoreline, like the Dutch. We should reject draconian rules to save folk from a remote and dubious peril. If Tim Flannery is allowed to take his chance living on his Hawkesbury property near sea level, Port Macquarie’s retirees should be permitted to do so too. They should not be evicted to “save” them from a dire fate in a future they will never see.
CLIFF OLLIER
Cliff Ollier is a geologist, geomorphologist, emeritus professor at the University of Western Australia