March 14, 2013

Ockham's Razor: 2012

ABC Radio National: Ockham's Razor

Joseph Bazelgette (1819–1891) [Civil Engineer]:
[How] difficult it is to induce the present generation to expend its capital in providing for the requirements of after generations.
(Building London’s sewerage system: an engineering wonder with lessons for today, 23 September 2012)

Contents


Antarctic Climate Change

An Engineering Wonder of the World

A Big Australia

A Prolonged, Painful and Fearful Death

Measures of Leadership: Reflections on Robert S McNamara

There's a Quiet Revolution going on in the Social Sciences


OCKHAM'S RAZOR


Robyn Williams (1944)

  • Testing times for medical science, 9 December 2012.
    Dr Rob Morrison: Professorial Fellow, Flinders University, Adelaide.

    [The UK] government recently ceased funding pseudoscientific health courses in British universities.
  • 50th Anniversary of Rachel Carson's 'Silent Spring', 28 October 2012.
    Jonathon Porritt: Founder Director, Forum for the Future.
  • The effect of climate change in Antarctica, 21 October 2012.
    David Neilson: Photographer.

    Antarctica contains 90% of the Earth’s ice and 70% of its fresh water.
    If all the ice melted the world’s sea levels would rise by 67 metres.
    In late 2009 the International Council for Science’s Scientific Committee on Antarctic Research, SCAR published the report Antarctic Climate Change and the Environment [which] references work by over 1,000 scientists. …

    From 1951 to 2006 the annual mean temperature on the western and northern parts of the Antarctic Peninsula rose by 2.9 degrees Celsius.
    [Winter temperatures have increased by] 5.6 degrees Celsius …

    [Mean] annual temperatures across West Antarctica have increased by 0.9 degrees Celsius [and across] East Antarctica … by 0.5 degrees Celsius [since 1957.]
    The global average temperature increase from 1951 to 2004 was 0.5 degrees Celsius.
    [According to a formal attribution study:]
    [Recent temperature] changes were not consistent with internal climate variability or natural climate drivers alone and were directly attributable to human influence.
    It is …. not clear what has caused the particularly high winter temperatures on the western side of the Antarctic Peninsula.
    However, the summer temperature increases are thought to be due to a complex sequence of events related to the existence of the ozone hole and increases in greenhouse gases.

    [During the southern winter a] band of high altitude westerly winds, the polar vortex, forms … and encircles Antarctica in the stratosphere above the Southern Ocean.
    These winds have increased in strength primarily due to the loss of stratospheric ozone.

    Although only small quantities of ozone-depleting chlorofluorocarbons and halon gases are now being released into the atmosphere, those that have previously been released will take 50 to 100 years to break down.
    Therefore each spring the ozone hole still forms.

    This loss of ozone cools the region within the stratospheric polar vortex and increases the strength of the winds near the vortex edge.
    Greenhouse gases [also contribute] to this cooling and strengthening process.

    During the summer and autumn [the strengthening high level winds propagate] through the atmosphere to increase [low level wind strength].
    These [low level winds have] become warmer as they take warm moisture from the oceans. …

    The Antarctic circumpolar current … warmed 1 degree Celsius from 1955 to 1998 and it is continuing to warm by about 0.2 degrees Celsius per decade – [faster] than the global average …

    The northern parts of the Antarctic Peninsula lie directly in the path of these stronger and warmer winds and seas. …

    On the eastern side of the Peninsula … the Prince Gustav, Larsen A and Larsen B ice shelves have all collapsed, half of the latter disintegrating in spectacular fashion over five weeks in early 2002.
    Larsen B had been stable for 12,000 years.
    The remaining large Larsen C ice shelf is gradually thinning at a rate of around 2 metres per year and scientists believe its northern edge may begin breaking up within the next decade.

    In the last 50 years ice shelves on the Antarctic Peninsula have reduced by 27,000 square kilometres.
    After the shelves collapse, glaciers feeding into them advance at a much faster rate, adding significantly more ice into the sea than is being created in their accumulation zones.
    [Ice] shelves float on the sea [so] they do not increase sea levels when they collapse …
    [However,] grounded ice calved into the sea from the accelerating glaciers does increase sea levels.

    [On the western side of the Peninsula the] annual mean [sea-ice] extent has declined by over 40% since 1979 …
    [Each year it forms] for three months less than it did [before]. …

    On the western side of the Antarctic Peninsula and in the South Shetland [and South Orkney Islands the numbers of Adelie and chinstrap] penguins have declined by at least 50% since 1980.
    [In] the South Sandwich Islands [they] have decreased by over 75%. …

    [These] Adelies and chinstraps feed almost exclusively on … krill.
    Krill larvae require winter sea ice as they feed on the algae found on the underside of the sea ice.
    Adult krill feed on phytoplankton which also requires sea ice for its life cycle.

    [Chinstrap penguins] are found only on the Scotia Sea islands, the Antarctic Peninsula and South Georgia.
    Adelie penguins … are found around the entire coast of Antarctica …
    [At] present the more southerly colonies are showing less variation.
    Some Ross Sea colonies have increased by 20%.

    [A] number of snails, clams and brachiopods have always had unusually thin and delicate shells, probably because there have been no shell-crunching predators such as crabs. …
    King crabs have recently been discovered … below 850 metres where the waters are warmer.
    The 600 to 400 metre waters of most of the shelf are colder, but are gradually warming, and within two decades king crabs could invade large areas.

    Shelled creatures are also at risk from the increasing acidification of the oceans [because it] dissolves carbonate shells and coral.
    Oceans today are 30% more acidic than they were 200 years ago. …

    The West Antarctic ice sheet is considered a marine ice sheet because the bedrock is in many places over 1,000 metres below sea level.
    [This type of ice sheet is considered to be] less stable than the much larger East Antarctic ice sheet where more of the bedrock is above sea level.
    [The] stronger circumpolar winds are dispersing cooler surface water northwards allowing upwelling of warm circumpolar deep water.
    The temperature of this warmer water is also increasing.

    There are fringing ice shelves along the coastal margins of the West Antarctic ice sheet.
    Warm water is penetrating under these shelves which are thinning in places at over five metres per year.
    [Glaciers flowing into these ice shelves are also accelerating: the] Thwaites, Smith and Pine Island glaciers, are moving at speeds at least 60% greater than they were in 1970. …
    The current rate of ice lost from these glaciers is equal to the current rate of ice lost from the entire Greenland ice sheet. …

    Climate models … predict that if there is a doubling of greenhouse gas concentrations by 2100, Antarctica will warm by around 3 degrees Celsius [and the] the annual average total sea ice area around Antarctica will decrease by at least 30%.
    [While this] may not be enough to cause serious melting of the large East Antarctic ice sheet [the impact] on the Antarctic environment is likely to be catastrophic.

  • Building London’s sewerage system: an engineering wonder with lessons for today, 23 September 2012.
    Mark Dodgson: Director, Technology and Innovation Management Centre, University of Queensland.

    Over 31,000 Londoners died between 1831 and 1854 in three outbreaks of cholera, a ghastly water-borne disease that kills quickly and indiscriminately.
    [Joseph] Bazelgette’s engineering of the sewer system [saved an estimated] 12,000 lives a year. …

    [Conservative] politicians and lawyers describing public investments [in infrastructure] as infringements of personal liberty and offenses against private property.
    The Economist …railed against large scale public investments in public sanitation. …

    [The] Metropolitan Board of Works [was established in 1855.]
    [It] eventually became the London County Council and then the Greater London Council which was disbanded by Margaret Thatcher as she believed it to be too powerful.

    Seven years in the planning Bazalgette’s scheme … involved the building of five intercepting sewers running across London. …
    [The] sewerage project employed 20,000 workers using picks and shovels and used 318 million bricks. …
    [It] entailed building [of] the Victoria, Albert and Chelsea embankments. …
    The Victoria Embankment … not only housed the sewers but also an underground railway, gas pipes and other services. …

    [Bazelgette also] oversaw the development of 3,000 streets and rehoused 40,000 people out of appalling slums.
    To sort out the growing traffic problems [he purchased eleven bridges] and removed the tolls.
    He improved [those] bridges and designed three new ones. …

    [The sewerage project met] with a series of disasters [and serious obstacles.]
    A gas pipe … ruptured killing a local resident.
    A tunnel collapsed killing 3 miners.
    In all there were 10 fatalities …
    [A] bricklayer's strike.
    [A] Chief Commissioner of Works who continually rejected his plans and a 45 member board with various factions.

    He dealt with these things with fortitude and tact [combined with a] great ability [to select] able colleagues, including those with which he had previously had disputes.
    He bore no grudges.

    He spent a great amount of time [promoting] his plans and practices to the public and parliamentarians and to various members of Boards and Commissions.
    [Some] 500 to 600 people were encouraged [to visit the works ‒ including] politicians and opinion formers.

    [It] was an expensive project … undertaken in a densely populated urban area. …
    [He] probably oversaw budgets of … around £1.l4 billion at present prices. …

    [He] developed very systematic contract management processes … that involved detailed specification of the work to be conducted and materials to be used …
    [When selecting the winning tender he] did not … always choose the lowest bid, preferring to work with contractors he knew and whose ability he respected. …

    [He] took the risk of experimenting with … a new kind of cement [‒ Portland cement.]
    [He contributed] to the development of the concept of quality control. …

    Bazalgette’s sewers now lead to the largest and most modern treatment works in Europe that generates electricity, uses residue to make breeze blocks and transfers remaining water into the Thames that is cleaner than that in the river itself. …

    When government assumes responsibility for large infrastructure projects these have to be
    • funded appropriately and securely,
    • provide opportunities for related and unexpected innovation and
    • ensure their leadership [displays the same] wisdom and forbearance [as] Joseph Bazalgette.

  • Australia's population debate, 19 August 2012.
    Ian Lowe: Emeritus Professor, Griffith University, Brisbane; President, Australian Conservation Foundation; Author, Bigger or Better — Australia's Population Debate, University of Queensland Press.

    Robyn Williams:
    I arrived in Australia 48 years ago this month.
    I arrived by boat for 10 quid.
    It wasn’t exactly leaky, but the Castel Felice, a converted troop carrier with the buoyancy of a brick and the cuisine of a remand home, was no castle of happiness.

    On landing I was surprised to find so few people.
    And apart from Australians there were quite a lot of Greeks and Italians.
    I was also surprised to find these immigrants were held in contempt in some quarters.
    And I thought those countries had helped invent civilisation.
    There was also one Sikh and he became a friend.

    Well, times change. …

    Ian Lowe:
    [We] don’t have a problem replacing ourselves.
    Each year about 100,000 Australians die and about 250,000 babies are born, so the population would grow by about 150,000 a year or about 400 a day if there were no migration.
    [Since] reliable contraception became available … the average number of children per adult woman [has fallen to] about 1.9 …
    [However, since] the number of adult women is still increasing rapidly as a result of the past birth rate and migration … there is still a large [natural increase. …]

    [John Howard and Peter Costello's baby bonus was] a wasteful solution to a non-problem.
    [The natural population increase] has never been less than 100,000 a year in the last 50 years. …

    Each year some people leave Australia and others arrive.
    [Net annual] migration [has also] averaged about 100,000 [(range 20,000 — 200,000).]
    [Except during the period when] the Howard government dramatically increased inward migration to well over 300,000.
    A significant cause was the scam of education schemes that were really back-door visa programs …
    The current government has clamped down on those arrangements but the annual net migration is still about 250,000 a year. …

    [Combining] birth rate and migration, the Australian population is now growing by about 400,000 a year or [one] million every two and a half years.
    [On] current trends it could be over 40 million [by 2040.]
    [Which raises the question:]
    Where would we get twice as much food [and] water?

    [The] infrastructure in all our major cities is failing to keep pace with the growing population …
    [This] is causing a decline in material living standards. …
    [The economist] Lester Thurow argued [25 years ago] that the average life of built infrastructure like roads, water supply, sewers and transport systems is about 50 years …
    [Therefore,] the annual bill for replacement would normally be about 2% of the total capital invested.
    If the population is growing by 2% the infrastructure bill is the normal 2% replacement plus an extra 2% for the new people, or 4% of the total capital.
    [Thus a] modest rate of growth [effectively] doubles the infrastructure bill.
    [Yet] the revenue base will only have grown by 2%.

    Faced with this problem Thurow predicted, governments would find themselves forced to sell public assets and put together improbable public/private partnerships to try to meet the impossible task of funding the infrastructure needs of the growing population.
    [This is] exactly what we have seen in Australia in recent years.

    One reason [that] the Bligh [Queensland state] government [was] swept from office was its fire sale of public assets to fund infrastructure.
    [Despite] those desperate measures … roads got more congested, public transport got more crowded and so on.
    [Ironically, Bligh's successor] Campbell Newman [in his former capacity as] Lord Mayor of Brisbane … ran up a huge public debt in an orgy of building roads, tunnels and bridges to try to dilute the public disquiet about growth. …

    The claim that we have a financial problem of an ageing population is completely false. …
    [According to the UN we] rank 43rd in the world … by average age …
    [Not] just younger than European countries but also younger than Canada, Cuba, Hong Kong and Singapore. …
    [In] Australia there are as many [people] under 15 as over 60 [19%].
    For at least a decade the numbers entering the workforce will be similar to the numbers turning 65. …
    [Even] if we did have an ageing society, migrants are typically about the same age on average as those already here …

    [Population growth certainly increases] the total size of the economy …
    [However,] there is vigorous debate among economists about whether it increases wealth per person …
    Comparative studies show that countries with growing populations need to spend on assets that are not economically productive like houses, so they don’t perform as well economically as those with stable populations.
    [There] may be a small net benefit [but this is offset by] the negatives of more crowded roads and public transport, less access to open space and recreation areas and so on. …

    [The] average household income [in Queensland] is projected … to grow from about $50,000 a year now to about $65,000 in 2030 if growth is tightly controlled, or to about $69,000 if the present pro-growth policies remain.
    [The] present growth rate of about 2% a year … will increase [the population by] about 50% by 2030.
    [So,] would you rather be 30% wealthier retaining the liveability of your area or 38% wealthier with 50% more cars on the road, 50% more people crowding on to public transport and trying to find space in the parks and children’s playgrounds? …

    The debate … isn’t helped by opportunistic politicians demonising the relatively small groups of boat people. …
    [Total] refugee intake [onshore (air and sea arrivals) and and offshore] is about 5% of migrants. …

    If we had zero net migration the population would stabilise in the 2030s. …

    The choices we are making now determine what Australia will look like in 2050.
    If we continue to encourage large scale migration and a high birth rate the population will be over 40 million and still growing rapidly.
    Holding migration down to around 100,000 a year or lower and phasing out incentives for larger families would enable us to stabilise the population below 30 million.
    There is no more important issue for an informed public debate.

  • Cattle and methane, 12 August 2012.
    Asa Wahlquist: Rural journalist.
  • A grandmother confronts creationist beliefs in her family, 22 July 2012.
    Mildred Studders: Skeptical Grandmother, Brisbane.
  • Beyond vox pop democracy: Deepening democracy in the internet age, 29 April 2012.
    Nicholas Gruen: CEO, Lateral Economics; Chairman, Australian Centre for Social Innovation.
  • GrowthBusters: Hooked on Growth, 27 May 2012.
    Dave Gardner: Documentary film-maker.
  • Christian animal sacrifice in the Holy Land, 8 April 2012.
    Jill Hamilton.

    As in Halal butchery, the knife goes through the neck slashing the … carotid arteries so blood pours out rapidly.
    The Armenians give salt to the animals in the mistaken belief that it lessens their pain.
    [Animals killed in this fashion] endure prolonged, painful and fearful deaths …

  • Is the carbon Landcare's missing link?, 25 March 2012.
    Phillip Toyne: Founding member of Landcare.
  • Measures of leadership: Reflections on Robert S. McNamara, 22 January 2012.
    Mark Dodgson.

    1. Empathise with your enemy
    2. Rationality will not save us
    3. There's something beyond one's self
    4. Maximise efficiency
    5. Proportionality should be a guideline in war
    6. Get the data
    7. Belief and seeing are both often wrong
    8. Be prepared to re-examine your reasoning
    9. In order to do good, you may have to engage in evil
    10. Never say never
    11. You can't change human nature

    Would you like to know more?

  • There's a quiet revolution going on in the social sciences, 1 January 2012.
    Ian Wilkinson: Professor, Business School, Discipline of Marketing, University of Sydney.

    … FuturICT [is] the visionary European project to build a planet earth simulator. …
    The pilot project is now underway and it’s funded for 2 million Euros. …

    The world is a highly complex system of interacting people and organisations …
    In order to understand such a system we have to be able to build models … with millions if not billions of simulated people and organisations in it.
    For example, the Epicast epidemiology model at Los Alamos National Laboratory has 300 million agents, one for every person in the USA. …

    [The] social, economic and business sciences [are currently] wedded to a mechanistic view of the world based on analogies with physical systems. …
    Societies and gases … are similar in that they are made up of millions of individual units interacting with each other.
    In a gas, the units are atoms and molecules.
    In society they are people.
    But society does not behave like a gas, no matter how much traditional economic modellers might want it to.
    [It] is not made up of millions of similar individuals randomly interacting with each other — so we cannot take averages and get a good representation of its behaviour, what in the natural sciences is called a mean field approximation.

    By focusing on fictitious representative ‘average’ individuals we are incapable of seeing extreme events that arise due to the heterogeneous, networked, dynamic complexity of real socio-economic systems.
    This is well illustrated by the fact that none of the usual economic models predicted the global financial crisis …

    … CRISIS a complex systems computer model being built of the European economy which includes different types of banks and households as well as other types of business firms.
    Instead of making heroic assumptions to make the model tractable and the maths work out such as highly efficient financial markets and perfectly economically rational actors, we rely on the power of computers to computationally solve the model under different realistic impossible conditions.

    This does not mean we can now predict the future of the world precisely …
    [Overall] order, to the extent there is any, emerges in a bottom up self-organising way from the local interactions taking place over time among all those involved.
    Rather like the way the flocking behaviour of birds emerges from each bird following some simple rules. …

    All we can hope to do is sketch out the range of possible futures and how likely they are under different conditions and the actions we might take. …
    We can use [such] complex systems simulation models as flight simulators for managers and policy makers [to] test out alternative policies and programs.

    [A] model of banking networks developed by Bob May, an Australian who pioneered this type of modelling in the early ‘70s and who became President of the Royal Society and Chief Scientific Adviser to the British Government.
    … May and his colleagues published a paper in Nature which showed a surprising paradox: the banking network as a whole becomes increasingly unstable as each individual bank diversifies its portfolio to spread its risk.
    From each bank’s perspective this is a reasonable thing to do, but if all banks end up being diversified in the same way when a crisis hits they are all blown away.
    That is, sensible individual behaviour makes everyone worse off. …

    The programs to build such models have become ever more friendly and freely available over time.
    One such is NetLogo which started out as a computer system to teach complex systems models and thinking to primary school children.
    [If] primary school kids can do it [presumably] university researchers can learn to do it too.

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