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They’ll give it the “old college try” for sure:

Critics of the teaching of evolution in the nation’s classrooms are gaining ground in some states by linking the issue to global warming, arguing that dissenting views on both scientific subjects should be taught in public schools.

“Our kids are being presented theories as though they are facts,” said State Representative Tim Moore of Kentucky.

In Kentucky, a bill recently introduced in the Legislature would encourage teachers to discuss “the advantages and disadvantages of scientific theories,” including “evolution, the origins of life, global warming and human cloning.”

The bill, which has yet to be voted on, is patterned on even more aggressive efforts in other states to fuse such issues. In Louisiana, a law passed in 2008 says the state board of education may assist teachers in promoting “critical thinking” on all of those subjects.

It’s an interesting idea, but the creationists, as is the case with their secularistic opponents, are looking at this the wrong way.

If there’s a lesson from the global warming fiasco that is now unfolding, it’s that science is an “open” discipline in that new things are always being discovered which either build on what we already know or refute it.  The problem with both evolution and climate change is that both are being presented as settled dogmas, in effect giving both a religious aspect.  (Climate change’s situation is complicated by duplicity amongst the scientists; evolutionary biology has experienced this in the past.)  Making either or both a religion defeat the whole purpose of scientific inquiry.

On the creationist side, their idea of promoting critical thinking is a good one.  But there’s the possibility for adjustments here also.  Intelligent Design advocates are for the most part open to this, but Young Earth Creationists may be in for some rude awakenings.

HT to Religion Clause.

As a sort of follow up to this post, more from the Coastal Engineering Manual on this subject.  I was unaware of the “Committee on Engineering Implications of Changes in Relative Mean Sea Level (CCMSL),” but they published a report and you can find it here.

There are a couple of things that “lay people” should keep in mind when looking at reports of sea level rise:

1. Sea level is relative to the land it meets with.  When people say that “sea level is rising,” is the sea level rising?  Or the land subsiding?  Or both?
2. “Sea level” is not a fixed datum, although it’s frequently presented with that kind of authority.  As the report notes, “…mean sea level has been fluctuating through a range of not more than 40-150 cm (in long-term fluctuations) for at least 300 years,” and “…there has been a general, longterm rise (with short-term fluctuations) probably not exceeding 200 cm during the last 1,500 years.”  It also notes that sea level can vary at different rates in different parts of the world.
   

Tidal datums.

(1) The apparent rise in worldwide sea level has been of great concern to the United States, as well as other countries, for several years. Much of this concern stems from the claims of some climatologists and oceanographers that the rise will accelerate in the future due to warming of the atmosphere associated with the “greenhouse effect,” a global warming produced by increased levels of carbon dioxide and other gasses in the atmosphere. Because of the potential consequences associated with sea level rise, a Committee onEngineering Implications of Changes in Relative Mean Sea Level (CCMSL) was formed to examine existing knowledge concerning sea level change, to document existing relative rise rates, and to provide recommendations concerning their conclusions.

(2) Relative mean sea level change can be defined as the difference between local changes in land elevation and global sea level changes. These changes result from a variety of processes, several of which can occur simultaneously. The following six processes can contribute to long-term relative mean sea level change; however, all processes do not necessarily apply to all geographic locations:

(a) Eustatic rise. Refers to a global change in the oceanic water level. Examples of eustatic rise include melting of land-based glaciers and the expansion of near-surface ocean water due to global ocean warming.

(b) Crustal subsidence or uplift from tectonic uplifting or downwarping of the earth’s crust. These changes can result from uplifting or cooling of coastal belts, sediment loading and consolidation, or subsidence due to volcanic eruption loading.

(c) Seismic subsidence. Caused by sudden and irregular incidence of earthquakes.

(d) Auto-subsidence. Due to compaction or consolidation of soft underlying sediments such as mud or peat.

(e) Climatic fluctuations. May also create changes in sea level; for example, surface changes produced by El Niño due to changes in the size and location of high pressure cells.

(3) The above processes have been evaluated with respect to their historical and potential contribution to sea level change on U.S. coasts. The Committee report assesses changes in sea level as well as the affected hydrodynamic processes and the effect on the coastal zone. The report also investigates feasible response strategies that could be used to mitigate the effects of sea level change. Although it is beyond the scope of this chapter to reproduce the contents of the report, conclusions relevant to this chapter are reproduced below.

(a) Relative mean sea level, on statistical average, is rising at the majority of tide gauge stations situated on continental coasts around the world. Relative mean sea level is generally falling near geological plate boundaries and in formerly glaciated areas such as Alaska, Canada, Scandinavia, and Scotland. Relative mean sea level is not rising in limited areas of the continental United States, including portions of the Pacific Coast.

(b) The contrasting signals concerning relative mean sea level behavior in different parts of the United States (and the world in general) are interpreted as due to differing rates of vertical motion of the land surfaces. Subsidence and glacial rebound are significant contributors to vertical land displacements.

(c) Large, short-term (2- to 7-year) fluctuations worldwide are related to meteorological phenomena, notably shifts in the mean jet-stream path and the El Niño-Southern Oscillation mechanisms, which lead to atmospheric pressure anomalies and temperature changes that may cause rise or fall of mean sea level by 15-30 cm over a few years.

(d) Studies of a very small number of tide gauge records dating more than 100 years (the oldest being Amsterdam, started in 1682) show that after removal of the subsidence factor where known, mean sea level has been fluctuating through a range of not more than 40-150 cm (in long-term fluctuations) for at least 300 years.

(e) The geological record over the last 6,000 years or so indicates that there has been a general, longterm rise (with short-term fluctuations) probably not exceeding 200 cm during the last 1,500 years.

(f) Monitoring of relative mean sea level behavior is at present inadequate for measuring the possible global result of future climate warming due to rising greenhouse gases.

(g) The risk of accelerated mean sea level rise is sufficiently established to warrant consideration in the planning and design of coastal facilities. Although there is substantial local variability and statistical uncertainty, average relative sea level over the past century appears to have risen about 30 cm relative to the east coast of the United States and 11 cm along the west coast, excluding Alaska, where glacial rebound has resulted in a lowering of relative sea level. Rates of relative sea level rise along the Gulf Coast are highly variable, ranging from a high of more than 100 cm/century in parts of the Mississippi delta plain to a low of less than 20 cm/century along Florida’s west coast.

(h) Accelerated sea level rise would clearly contribute toward a tendency for exacerbated beach erosion. However, in some areas, poor sand management practices or navigational modification at channel entrances has resulted in augmented erosion rates that are clearly much greater than would naturally occur. Thus, for some years into the future, sea level rise may play a secondary role in these areas.

(i) As noted previously, the two response options to sea level rise are stabilization and retreat. Retreat is most appropriate in areas with a low degree of development. Given that a “proper” choice exists for each location, selecting an incorrect response alternative could be unduly expensive.

(j) There does not now appear to be reason for emergency action regarding engineering structures to mitigate the effects of anticipated increases in future eustatic sea level rise. Sea level change during the design service life should be considered along with other factors, but it does not present such essentially new problems as to require new techniques of analysis. The effects of sea level rise can be accommodated during maintenance periods or upon redesign and replacement of most existing structures and facilities. There are very limited geographic areas where current subsidence rates may require near-term action as has been the case in Japan and Terminal Island, California.

(4) The above conclusions represent the state of knowledge on the subject of relative sea level change. For additional information, the reader is referred to the Committee report. It presents a complete and comprehensive investigation of the subject based on known facts and engineering and scientific principles.

(5) For the purposes of this report, the primary conclusion is that, with some regional exceptions, sea level is not rising at a rate to cause undue concern. Results of the report indicate an average sea level riseover the past century of approximately 30 cm/century on the east coast, and 11 cm/century on the west coast, and a range along the Gulf of Mexico coast of less than 20 cm/century along the west coast of Florida to more than 100 cm/century in parts of the Mississippi delta plain. The above summary remarks lead to the conclusion that normal design criteria should be followed in which the design life of a project should consider the possible local relative sea level rise rates shown above.

Another excerpt from the Coastal Engineering Manual on this subject:

I-3-4.  Modern Age

After the fall of the Western Roman Empire, a long hiatus in coastal technology and engineering prevailed throughout most of the European world with a few exceptions.  Little is recorded on civil engineering achievements during the Dark and Middle Ages.  The threat of attack from the sea caused many coastal towns and their harbours to be abandoned.  Many harbours were lost due to natural causes such as rapid silting, shoreline advance or retreat, etc.  The Venice lagoon was one of the few populated coastal areas with continuous prosperity and development where written reports document the evolution of coastal protection works, ranging from the use of wicker faggots to reinforce the dunes to timber piles and stones, often combined in a sort of crib work.  Protection from the sea was so vital to the Venetians, that laws from 1282 to 1339 did not allow anyone to cut or burn trees from coastal woods, pick out mussels from the rock revetments, let cattle upon the dikes, remove sand or vegetation from the beaches or dunes, or export materials used for shore protection (Franco 1996).

In England, coastal engineering works date back to the Romans, who recognized the danger of floods and sea inundation of low-lying lands.   On the Medway, for example, embankments built by the Romans as sea defence remained in use until the 18th century (Palmer and Tritton Limited 1996).  The low-lying lands, consisting of recently-deposited alluvial material, were exceeding fertile but were also vulnerable to flooding from both run-off and storm surges.  In the Middle Ages, the Church became instrumental in reclaiming and protecting many marshes, and monks reclaimed portions of the Fylde and Humber estuaries.  In 1225, Henry III constituted by Charter a body of persons to deal with the question of drainage (Keay 1942).

Across the North Sea, the Friesland area of the Netherlands had a large and wealthy population in the period 500 – 1000 A. D., and increasing need for agricultural land led to building of sea dikes to reclaim land that previously was used for grazing (Bijker 1996).  Water boards developed in response to the need for a mutual means to coordinate and enforce dike maintenance.  These boards represent some of the earliest democratic institutions in the Netherlands.

Engineering and scientific skills remained alive in the east, in Byzantium, where the Eastern Roman empire survived for six hundred years while Western Rome decayed.  Of necessity, Byzantium had become a sea power, sending forth fleets of merchant ships and multi-oared dromonds (swift war vessels) throughout the Black Sea and Mediterranean.  When the weary soldiers of the first crusades reached Byzantium’s capital city, Constantinople, in 1097, they were amazed and awed by its magnificence, sophistication, and scientific achievements.  Constantinople was built on the hills overlooking the Golden Horn, a natural bay extending north of the Bosporus.  Marble docks lined the waterfront, over which passed the spices, furs, timber, grain, and the treasures of an empire.  A great chain could be pulled across the mouth of the Golden Horn to prevent intrusion by enemy fleets.  A series of watch towers extended along the length of the Sea of Marmara, the Bosporus, and the south shore of the Black Sea, and the approach of an enemy fleet could be signalled to the emperor within hours by an ingenious code using mirrors by day and signal fires by night (Lamb 1930).

The Renaissance era (about XV – XVI centuries) was a period of scientific and technologic reawakening, including the field of coastal engineering.  While the standards for design and construction remained those developed primarily by the Romans, a great leap in technology was achieved through the development of mechanical equipment and the birth of the hydraulic sciences including maritime hydraulics (Franco 1996).

“The Italian School of Hydraulics was the first to be formed and the only one to exist before the middle of the 17th century” (Rouse and Ince 1963).  Leonardo da Vinci (1465-1519), with his well-known experimental method, based on the systematic observation of natural phenomenon supported by intellectual reasoning and creative intuition, could be considered the precursor of hydrodynamics, offering ideas and solutions often more than three centuries ahead of their common acceptance.  Some of his descriptions of water movement are qualitative, but often so correct, that some of his drawings could be usefully included in a modern coastal hydrodynamics text.  The quantitative definition and mathematical formulation of the results were far beyond the scientific capabilities of the era. Even so,  da Vinci was probably the first to describe and test several experimental techniques now employed in most modern hydraulic laboratories.  To visualize the flow field, he used suspended particles and dyes, glass-walled tanks, and movable bed models, both in water and in air. The movement from kinematics to dynamics proved impossible until the correct theory of gravitation was developed, some two centuries latter by Sir Isaac Newton (Fasso 1987).  The variety of hydro kinematics problems dealt with in da Vinci’s notebooks is so vast that it is not possible to enumerate them all in this brief review.  In the 36 folios (sheets) of the Codex Leicester (1510), he describes most phenomena related to maritime hydraulics.  Richter (1970) provides an English translation of da Vinci’s notebooks (Franco 1996).  The scientific ideas of the Italian Renaissance soon moved beyond the confines of that country, to the European countries north of the Alps.

I-3-5.  Military and Civil Engineer Era

After the Renaissance, although great strides were made in the general scientific arena, little improvement was made beyond the Roman approach to harbour construction.   Ships became more sea-worthy and global navigation became more common.  With global navigation came the European discovery of the Americas, Australia, New Zealand, Indonesia, and other areas of the world, soon followed by migration and colonization.  Trade developed with previously unreachable countries and new colonies.  France developed as the leader in scientific knowledge.  The French “Génie” officers, who, along with their military task, were also entrusted with civilian public works, are reportedly the direct ancestors of modern civil engineers. Sébastien le Prestre de Vauban  (1633-1707) was a builder of numerous fortresses and perfected the system of polygonal and star shaped fortifications.  His most eminent public works project was the conversion of Dunkirk into an impregnable coastal fortress.  Apart from the construction of several forts, there were extensive harbour and coastal works, including the excavation of canals and harbour basins, the construction of two long jetties flanking the entrance channel, and the erection of storehouses and workshops.  A great lock, a masterpiece of civil engineering, was built at the entrance to the Inner Harbour.  Vauban himself designed and supervised the lock construction.  Unfortunately, no more than 30 years after its completion, the fortress was destroyed as a consequence of the Spanish War of Succession.  Vauban’s projects provide a good example of engineering methods and lucidity.  They consisted of an explanatory memorandum, several drawings, and a covering letter.  The memorandum had four sections:  (1) general background of the scheme; (2) detailed descriptions of the different parts, with references to the drawings;  (3) cost estimates;  (4) features and advantages of the work.  It was during this time that the term “Ingenieur” was first used in France, as a professional title for a scientifically-trained technician in public service.

While France enjoyed a leading position in Europe with regard to exact sciences and their applications to technical problems, a social and economic revolution later known as the “Industrial Revolution” was taking place in England.  The riding-horse and the packhorse gave way to the coach, the wagon and the barge.  Hard roads and canals replaced the centuries old soft roads and trails, dusty in dry weather and mud-bound during rains (Straub 1964).  Steam power allowed industry to be concentrated in factories that required continuous supply of raw materials and export of manufactured goods.

In the 18th and 19th centuries, advances in navigation and mathematics, the advent of the steam engine, the search for new lands and trade routes, the expansion of the British Empire through her colonies, and other influences, all contributed to the revitalization of sea trade and a renewed interest in port works.  As the volume of shipping grew, more vessels were needed and as the dimensions of the new vessels became larger,increased port facilities were necessary.  Ports of the world experienced growing pains for the first time since the Roman era, and, except for the interruption caused by two world wars, port needs continue to grow (Quinn 1972).

References for this are the same as the preceding sections, except to add the following:

• Bijker, E. W.  1996.  History and Heritage in Coastal Engineering in the Netherlands.  History and Heritage of Coastal Engineering, N. C. Kraus, ed., Coastal Engineering Research Council, American Society of Civil Engineers, Reston, VA, pp. 390 – 412.
• Fasso, C. A.  1987. “Birth of hydraulics during the Renaissance period,” Hydraulics and Hydraulic Research; a Historical Review, IAHR, G. Garbrecht Editor, Balkema, pp 55-79
• Keay, T. B.  1942.  Coast Erosion in Great Britain, General Question of Erosion and Prevention of Damage; and the Drainage of Low-Lying Lands.  Shore and Beach, Vol. 10, No. 2, pp. 66 – 68.
• Lamb, H.  1930.  The Crusades, Iron Men and Saints, Doubleday, Doran & Co., Garden City, NY.
• Palmer, R., and Tritton Limited (eds.).  1996.  History of Coastal Engineering in Great Britain.  History and Heritage of Coastal Engineering, N. C. Kraus, ed., Coastal Engineering Research Council, American Society of Civil Engineers, Reston, VA, pp. 214 – 274.
• Richter, J. P.  1970.  The Notebooks of Leonardo da Vinci, Dover Publishing, New York, NY.
• Rouse, H. and Ince, S.  1963. History of Hydraulics, Dover, NY.
• Straub, Hans.  1964.  A History of Civil Engineering, English Translation by Erwin Rockwell, The M.I.T. Press, Massachusetts Institute of Technology, Cambridge, Massachusetts, 258 p.