Ask Your Mates Open Forum

Expand all | Collapse all

Marine Engineering

  • 1.  Marine Engineering

    Posted 17-07-2015 13:34
    The prevailing mantra on Climate Change envisages a future where sea levels will rise due to anthropogenic Global Warming. My understanding of science and geology suggests a different scenario. About half of Earth's age ago, Earth experienced its first Ice Age. Since that first occurrence, Ice Ages have occurred ever more frequently. This is understandable because the Sun's energy output is gradually decreasing. The theory of an inevitable "Snowball Earth" is most plausible. Maybe we should be designing for gradual lowering of sea levels. ------------------------------------------- Neville Harington SOUTHSIDE QLD -------------------------------------------

  • 2.  RE: Marine Engineering

    Posted 18-07-2015 20:37

    Interesting question, and I am sure the scientists who work in this area will have taken it into account.  

    However, your question highlights a more fundamental issue - the issue of managing risk and assigning probabilities to possible future scenarios.  If we can get better at this we can plan more effectively for the future.  So if the balance of probabilities is that sea levels will rise in the next x years, then fall thereafter for a period of y years what does this do to our planning?  It certainly means we need to be less dogmatic and more flexible in our approach.  But it also means we need to focus on providing better information to decision-makers to help them to optimise the spend of the scarce resources we have, to design infrastructure that is capable of responding to both scenarios (a significant challenge in itself!) and to work with taxpayers to ensure they understand the need for the different courses of action.

    A challenge indeed for our emerging leaders.

    David Hope
    Principal Consultant
    Skilmar Systems Pty Ltd


  • 3.  RE: Marine Engineering

    Posted 18-07-2015 20:37
    The key is to plan and design infrastructure for increasing extremities, whether they be incidental (eg king tides, storm surges) or incremental (eg extremes in heat/coolth for roads/rail/built frames etc) and extremes of weather periods such as flood and drought.

    Robyn Evans
    General Manager Infrastructure Development & Works
    West Wimmera Shire Council


  • 4.  RE: Marine Engineering

    Posted 22-07-2015 13:46

    This view is contrary to scientific consensus on many levels and defies both current observational
    and theoretical science.
    Good luck with progressing it.

    Michael Casteleyn
    Stromwater Engineer
    Woollahra Municipal Council


  • 5.  RE: Marine Engineering

    Posted 23-07-2015 12:10
    Michael and Neville are both right.
    Snowball Earth is true and probably will occur again due to natural causes, BUT many thousands of years into the future. It should be ignored at present and any way what can we puny humans do about it with our present technology.

    Anthropogenic warming is partially the cause of temperatures rise and sea level rise, BUT not the  total cause - as expounded by many eminent scientists but with little publicity. The % cause apportionment is what is unknown but is being studied by a number of scientists - some think about 50/50.
    It is well known by many scientists and proven that the Earth goes through heating and warming cycles by natural causes, eg in Years 00 & 1100, the Earth's temperature was over 1 degree C warmer than today (about 1000 the Vikings colonised and farmed parts of Greenland and then perished when the cooler temperatures returned - anyone who has been to Greenland as I have, in 2014 will see farming here as ridiculous); from 1450 to 1850 the Earth was about 1 degree C cooler than today. These cycles have been going on for thousands of years - there are also mini cycles in between.
    This means that all the heating that Earth has experienced over the past 10-20 years is partially due to natural causes - we humans cannot upset these as the causes are mostly beyond Earth (forget the minor disruptions due to volcanoes, etc). If you see the above cycles - what cycle is the Earth now heading into - a cooling cycle which is going to be offset by our CO2 problem - in some ways this is good as cooling reduces food yields and increases energy use (heating) - which is what occurred in the 1450 to 1850 period.
    A very good book by an eminent environmental scientist who is a strong believer in alternative energy sources and was an advisor to German Chancellor Angela Merkel is:   The Neglected Sun by Professor Fritz Vahrenholt - keep an open mind and read this book which contains a lot of factual material with a large Glossary.
    The Professor does not say that we should ignore the CO2 problem but due to the natural cycles, we have more time to amend our ways without drastically affecting our economies and standard of living, ie progress effectively and efficiently, do not rush in.

    Paul Ritchie
    Ritchie Civil Engineering Pty Ltd
    Gladesville NSW


  • 6.  RE: Marine Engineering

    Posted 11-08-2015 11:40
    Paul Ritchie's message is well reasoned and he is right to question any 'popularised' theories on climate change. Prof Ian Plimer's book 'Heaven and Earth: Global Warming - The Missing Science' is worth a read as it also presents an alternate view. I know the book has been challenged and ridiculed by the 'green extreme' but we need to listen to all the arguments and exercise caution in any long term planning. If short term global warming (regardless of the root cause) will raise sea levels we must deal with that, and not just find a group to blame or look for a cure that may not work or may come too late. We are dealing with forces and phenomena which are on geological time scales, a hundred years is meaningless in that scenario. The earth will survive, we have to adapt to survive.

    Ian Gay
    Fraser Coast Regional Council


  • 7.  RE: Marine Engineering

    Posted 13-08-2015 17:26
    I have recently was engrossed reading the thread associated with the initial post which is obviously passionate to a number of us.

    I wanted to add, despite all the opinions presented (perhaps including mine) have we have actually lost sight of whats important?

    We are all focused on debating what might or might not happen when in reality despite which side of the debate you sit being scientific, theologian, for or against, we really don't know. After all it wasn't too long ago the scientific belief was the world was flat.

    Anyone who observes Scientific Data cannot doubt weather systems and patterns are changing.  But like dogs chasing cars we are focused on the assumed outcome - an outcome which is as likely to be wrong as correct.  Our focus needs to be on the things that we can control.

    What we can control is the solutions we present to problems.  Unfortunately despite all the dialogue and the illusion of change, we are fundamentally doing nothing different - the same thing.  If we are serious about effectuating and even remotely doing anything to affect future outcomes we must start focusing on what is important and not on what is not.

    We need to start becoming resource and energy efficient - and that is doing more with less - by using fewer resources (or less scarce resources) to accomplish the same goals. - and the starting point is firstly having a natural affinity for our natural environment similar to our indigenous former custodians.

    As Engineers our focus needs to design and develop solutions that consume resources no faster than the rate that nature can re-replenish them - the first law of thermodynamics.  This is a big ask but as the people responsible for this shift we are still stuck doing the same thing - with our minds off with the fairies debating probabilities.     

    Lets all get real and start taking affirmative action and doing things that take serious steps to sustainable solutions - I am confident when we start to respect our environment - she will start respecting us.
    James Crisera
    Queenstown SAau


  • 8.  RE: Marine Engineering

    Posted 14-08-2015 16:52
    Just to add some further things to think about. 

    In 1996 the Australian Council of Professions published a short document entitled "Dealing With Risk: Managing Expectations".  It was basically a 10 point plan for professionals to consider in their particular profession.  Each of the 10 points is important but I think that four in particular belong in this debate. 

    They are:

    "1.  DUTY OF CARE: Recognise your professional responsibility to the community.

    You have a responsibility to the community and to those who might be exposed to a known risk.

    You have a particular responsibility when forming a judgement about the tolerability of risk.

    4. APPROACH: Take a systematic approach to risk issues.

    Recognise that risk management should be an integral part of all aspects of professional activity, it should always be conducted systematically and be capable of audit whenever this is possible.

    Look for potential hazards and risks associated with your area of work or work‑place, and seek to ensure that they are appropriately addressed.

    Balance reliance on codes of practice with project specific risk assessment; be open minded and do not hide behind regulations.
    Do not exceed your level of competence on risk issues or ask others to do so; seek expert assistance where and when necessary.

    5. JUDGEMENT: Use professional judgement and experience.

    Judgement is required to match the approach to the nature of the hazard and the level of risk; for example, the approach might vary from a simple assessment to a formal safety assessment.

    Uncertainty is a feature of risk management. Be aware of this, and use risk assessment methods as an aid to judgement, not as a substitute for it.

    Understand that exercising judgement is itself a risk which has to be accepted.

    10. PUBLIC AWARENESS: Encourage public understanding of risk issues.

    Contribute to public discussion when and where you have the opportunity, so that there can be greater awareness of, and better information available on, major risk issues.

    Seek to encourage a positive public perception of the role of professionals in the  management of risk.

    Contribute to improving communications on risk issues between your professional body and the community."

      Fundamentally, we should not let our personal preferences over-ride our professional responsibilities.  And as for not following the consensus view, be very sure that your action in going against a consensus is supportable and defensible.  Loss of life, loss of property, serious injury and serious damage to the environment need to be considered in assessing risk.

      David Hope
      Principal Consultant
      Skilmar Systems Pty Ltd


    1. 9.  RE: Marine Engineering

      Posted 14-08-2015 16:52
      Hi all, I have been meaning to respond to this thread all week.

      Imagine that it was possible to create a time lapse video of the changes in the Earth over the last billion years and you ran it at 1000 years a second. The movie would run non-stop for just over eleven and a haf days.  Continents would drift, great white ice sheets would rapidly expand and contract from the poles, expanses of green, brown and yellow would expand and contract as green lands turned to desert and vice versa.  About four days into the video the Earth would be nearly pure white for a while.  Every now an then there would be a flash and the landscape would change dramatically as a result of an asteroid or comet impact, but most of the time there would be a mesmirising cyclic regularlity to the changes. But right at the very last fraction of a second of the film, something wonderful and new and almost impossible happens.  Out of nowhere and totally unexpectedly great cities and road networks appear.  New lakes appear, small seas disappear.  The night side of the planet lights up.  Splotches and filaments of light are everywhere. Change is everywhere you look.

      Yes we the human technological civilisation have changed the planet, but it is something to wonder at not be alarmed by.  Yes some of the changes we've caused are problematic at the moment, but on the whole it is two steps forward, one step back not the other way around.

      It is clear to me that however much Science & Technology has contributed to our current problems, it is also the answer to our problems.  Science & Technology is our best and possibly only chance going forward. 

      Yes, we should be designing our marine structures with an eye to possible future changes in sea level, but we should also realise that science and technology is changing everything (not just the climate) at an almost impossibly fast rate and just concentrating on one small part of the change at the expense of the big picture is ... I don't know ... missing the big picture.  

      Wayne Eddy
      Strategic Asset Planning Coordinator
      City of Whittlesea


    2. 10.  RE: Marine Engineering

      Posted 23-07-2015 12:14
      Hi Neville

      You are probably correct, however, you are also talking about events that occur on a geological time scale, not a human one.

      By the time the next major ice age happens on earth, I am willing to bet that all human life has long since moved on.

      Probably better to keep preparing for the sea level rise, at least in the short term (next 10 generations at least, if we do not anihilate ourselves before then).

      Catherine Kinsey
      Co-ordinator Stormwater and Structural Design
      Campbelltown City Council


    3. 11.  RE: Marine Engineering

      Posted 23-07-2015 12:44
      I recently viewed a very well reasoned unemotional professional summary of the situation by Kerry Emanuel an MIT (Massachusetts Institute of Technology) Professor of Meteorology (the interdisciplinary scientific study of the atmosphere) which I encourage everyone to watch at:

      (His MIT website is at

      Godfrey Bridger
      Strategic Lighting Partners Ltd
      Hamilton, New Zealand


    4. 12.  RE: Marine Engineering

      Posted 27-07-2015 14:51
      Hi Mates,

      I strongly endorse Michael's comments. The records show that sea levels around the globe are rising, with the rate of rise increasing decade by decade. Likewise, accurate monitoring shows that the concentrations of greenhouse gases in the atmosphere are steadily increasing and global average temperatures are increasing decade by decade. Climate change is not something that we can ignore, leaving it to our children and grandchildren to deal with. The climate is already changing.

      The reality of climate change, and the contribution of human activities to climate change, is accepted by the overwhelming majority of the world's climate scientists, people who have dedicated their whole careers to this challenging branch of science. The reality of climate change is also accepted by the United Nations, most world governments, all the major political parties in Australia (yes even Tony Abbott), Engineers Australia, IPWEA and the Pope.

      When we have a serious illness we seek advice and treatment from the most knowledgeable medical specialists in order the maximise the likelihood of being cured.  But, when human society is faced with the enormous challenge of climate change, it is hard to understand why some people prefer to ignore the overwhelming advice of the world's climate scientists and, indeed, sometimes disparage their valuable work.

      Even if some engineers prefer to disregard the overwhelming consensus on the reality of climate change, they are obliged in their work to have regard to the relevant Australian standards.  Unfortunately, due to the long time required to update them, most Australian standards do not yet account for climate change. However one standard that does allow for climate change is AS 4997 - 2005. Guidance for the Design of Maritime Structures. In section 4.6 - Sea Level Rise (global warming) the standard suggests allowances that should be made for sea level rise.  Because that standard was revised in 2004 those allowances are smaller than would be considered appropriate today, but the key principle of explicitly allowing for sea level rise when designing maritime structure stands.  As well, the next edition of Australian Rainfall and Runoff, due out at the end of  this year, will provide guidance on how to consider climate change when undertaking flood and stormwater design and analysis.
      Dr Stephen Lees
      National Director Sustainability
      (m) 0412 264 187


    5. 13.  RE: Marine Engineering

      Posted 06-08-2015 10:39
      Having reviewed the comments made by respondents, we must accept that Earth's Climate has always been subject to change by a variety of dynamic/physical influences. We must also accept that the most dramatic changes have been the promulgation and retreat of Ice Ages. The known influences of Earth's Climate can be categorised as

      Cyclical Dynamics - Orbital variations regarding earth's distance from the sun
                                            Obliquity variations regarding the degree of tilt of earth's axis of rotation
                                            Precession variations regarding the rotating of  earth's axis of rotation

      Random Events      - Asteroid impacts
                                           Volcanic activity
                                           Sunspot activity

      Dependent Chemistry - Atmospheric water vapour
                                                Atmospheric carbon dioxide

      These influences impact on Earth's Climate to greater and lesser degrees. My judgment is that the the decreasing order of influence is:
      Orbital variations   Asteroid impacts    Volcanic activity    Sunspot activity    Obliquity variations   Precession    Water vapour    Carbon dioxide 

      The consensus among climate scientists is that "the clear and present danger for earth is warming by atmospheric carbon dioxide". The prevailing consensus in the sixteenth century was that the sun revolved around the earth- Galileo was imprisoned for having the temerity to claim otherwise. Science should never be a matter of consensus. 

      Neville Harington


    6. 14.  RE: Marine Engineering

      Posted 08-08-2015 00:50
      This has been an interesting discussion, with all sides sharing valid points. However, if we do a rough FMEA of the planet Earth with associated risks and timeframes, I feel the most critical influences we need to address are Climate Change due to greenhouse gases (medium to high consequences, but very high probablility due to the fact that the effects will take place in a matter of decades rather than millenia) and the impact of asteroids with a diameter of greater than10km (very unlikely probablility in the next 10,000 years, but the critical consequences being the end civilization as we know it).

      It's a balancing act of short- and long-term knowns and unknowns that we have to decide what is in our power to mitigate. We have to ask ourselves what would be worse: Do something to mitigate a threat then never have it occur or do nothing and have the threat occur which causes suffering to others?

      Brad Bellows
      City of Ottawa
      Ottawa ON


    7. 15.  RE: Marine Engineering

      Posted 11-08-2015 11:37
      Engineers used to be the people who considered all aspects of a problem in depth before coming to a conclusion. Results were then most often technically correct and cost effective. To achieve this end a lot of study, training and consideration of current circumstances needed to be put together and given depth of thought. Politics did not enter into the engineers' decisions.

      Many of today's engineers do not put this depth of research together with their initial training before coming to a conclusion about whether or not man produced carbon dioxide will have any effect on to the planet. It is currently"politically correct" to push the view that carbon dioxide is a pollutant and causing the planet to warm disastrously. Engineers should not be agreeing with this claim just because it is reported that 'so and so' agrees with it. They should carry out their own research to come to a well-considered opinion. Only then are they able to correctly advise their Councils and others on the correct way forward.

      Please avoid the hysteria and do this!

      William Peach
      Self Employed - NQ


    8. 16.  RE: Marine Engineering

      Posted 11-08-2015 11:36

      Hi Neville,

      Actually the sun around the earth fallacy was pushed by the church not scientists. Most civilisations (through their educated classes) knew very well about the true motion of the cosmos, think Mayan, Egyptian, Greek, Roman, Persian, Celt, etc. The Christian church sought to limit intellectual/scientific pursuits to maintain their power and place at the top of the wealth and power tree. They were able to get away with it for so long mainly because there was no mainstream/widespread scientific method available. Again this was because it was easier to control ignorant masses so education was limited to a few elites. As soon as the scientific method via the renaissance arrived on the scene followed by the industrial revolution and education for the emerging middle classes the actual facts began to become more accepted and people's lives have improved.

      For mine I'll stick with the scientists on this one because as an engineer it is my job to manage risks. Climate Change (whatever its cause) is clearly a risk and it is prudent to mitigate against its potential impact.

      I think your posts miss the point for an engineering forum. Any engineer who works in hydrology and/or flood risk knows the weather patterns are changing and changing rapidly and there is an underlying trend towards more extreme events. This is irrefutable. The question for an engineer is not what is causing this change (there are thousands of highly qualified scientists working on this question) but whether we should do anything about it? if the answer is yes we must mitigate the risk (as is our responsibility) then the question becomes what should we do about it? That's the space I work in.



      Darren Carlson | Senior Engineer | Kingborough Council

      6211 8239 | Mobile 0407 872 606 | Fax (03) 6211 8211 
      Address Civic Centre, 15 Channel Hwy Kingston TAS 7050
      Email | Web


      Please consider the environment before printing this email. This email and any attachments is strictly confidential and should be read only by those persons to whom it is addressed and its content is not intended for use by any other persons. If you are not the intended recipient you must not use, copy or distribute it. If you have received this message in error, please destroy and delete the message along with any attachments from your computer and notify us immediately.


      This email has been scanned by the Symantec Email service.
      For more information please visit


    9. 17.  RE: Marine Engineering

      Posted 12-08-2015 11:38
      Hi Darren,

      For what its worth I think your post was excellently worded and I totally agree with you. Engineers are do-ers! 
      Godfrey Bridger Managing Director Strategic Lighting Partners Ltd
      49 Poplar Lane, RD4 Hamilton 3284 New Zealand
      Ph: +64 7 859 0060 
      Mob: +64 (0)21 274 3437


    10. 18.  RE: Marine Engineering

      Posted 13-08-2015 17:19
      Recent postings prompt me to further respond to Engineers' responsibility to undertake design with full consideration of all potential risks. The risk of  predicted sea level rise due to the alleged impact of a greenhouse gas called carbon dioxide is important to me. By way of background, the address on climate change presented by Dr Kerry Emanuel (as recommended viewing by Godfrey) is worth noting. He emphasised just how stable has been Earth's climate for the past 7,000 years, having due regard to the Medieval Warm Period (700-1200 years ago) and to the Mini Ice Age (200-600 years ago). These events, as well as current perspectives of climate change, are simply variations within the current stable period. Darren says that it is irrefutable that there is an underlying trend towards more extreme events. Is this really so, or does modern technology (satellite imagery, cell phone photography, etc) enable the capture of more visual and widespread events? I reckon all current weather events are within probable variations pertaining to a relatively stable climate regime. It is worth noting that temperatures and sea levels have been basically stable this century. William says that Engineers should come to a well-considered opinion (on climate change) and then advise their Councils on the correct way forward.
      Put yourself in the shoes of an Engineer who is advising a client on a major multi-million five star resort project located located near the junction of a river estuary and a tidal strait. The project has the full support of the local Council and the local community. There exists 150 years of recorded inundation levels, and it is expected to design for less than 5% chance of inundation of main floor levels within the next 100 years. It is accepted that, within the last 150 years, it is unlikely that the possible extreme event of a king tide coinciding with both a major river flood and a storm surge ever occurred. Council Engineers accept that one metre freeboard above the highest recorded inundation level plus another metre to cater for likely wave effect is a reasonable assessment. Such design gives the client  a 90% chance of achieving a Return on Investment (ROI) of 6% pa for the life of the project. None of the above caters for sea level rise due to global warming. To cater for an additional one metre lift in main floor level reduces the ROI to 5% which makes the project non-viable. Some adherents of climate change ideology would say "just too bad.....shouldn't be built". Some such as myself would say that worthwhile projects and infrastructure should not be jettisoned because of some dubious prediction.

      Neville Harington


    11. 19.  RE: Marine Engineering

      Posted 23-07-2015 12:00
      Hi Neville,
      Interesting observation. It is true that there are overlapping "natural" cycles that trigger climate events based on the amount of solar radiation hitting the earth. In the longer (geological) term, there are the sun cycles, planetary wobble and orbit of the earth and occur roughly every 11,000, 22,000 and 100,000 or so. There are also "random events such as super-volcano eruptions that trigger ice ages, but who can plan for that! As for local planning, we have to account, as best as possible, for the "here and now" which seems to be a rising sea level derived from anthropogenic influences and set to occur over the next 100 or so years.

      Jason Errey
      OEMG Global


    12. 20.  RE: Marine Engineering

      Posted 24-07-2015 12:24
      There's no doubt any asset design that is required to provide service over the geological timeframe, 100s of thousands of years will need to accomodate significant variation in climate related impacts -ocean level, temperature variation etc. If only our assets could give us this sort of service life! I think at an asset level its important to design for the expected service life of the asset and get the best possible (i.e peer reviewed) projections to understand the risk profiles of the specific area the asset is opperating in. Free of any mantra or anything else. Peer reviewed science should guide this process, after all its physical asset management were talking about, not politics.

      Nic Moodie
      Katoomba NSW


    13. 21.  RE: Marine Engineering

      Posted 23-07-2015 12:15
      I wish to thank the respondents who have commented on my submission. The narrow focus of my initial writing was the inevitability of another Ice Age. David commented on the need to provide better information to civic leaders and decision makers to "help them to optimise the spend of scarce resources". I totally agree! In the early years of this century, one of Australia's foremost climate scientists predicted that, during the course of this century- global temperature would steadily rise, sea levels would rise by one metre and our dams would dry up. The results prove otherwise- global temperatures havn't changed ( they call it a warming pause), sea levels havn't changed, and most of our major dams are at near-full capacity. How are engineers expected to cater for such questionable scientific predictions? Leading world climate scientists have now conceded that the nexus between atmospheric carbon dioxide levels and temperature is not as strong as that on which computer climate modelling was based. Carbon dioxide is a colourless, odourless, non-polluting gas represented by one part in 2,500 in our atmosphere. Those who understand the carbon cycle would know that atmospheric carbon dioxide is an essential requisite for life on earth. Furthermore, increasing levels of atmospheric carbon dioxide would improve plant and crop production across the globe. Any meagre temperature rise attributed to burning fossil fuels would have the beneficial effect of delaying the next Ice Age. Neville Harington SOUTHSIDE QLD -------------------------------------------