bluuebunny/crossref_metadata_2025 huggingface dataset:
The Operation of Light Aircraft
Authors: Stringer F. S. , Powell Claud , Black A. N.
Published: November 2009

An informal discussion on the operation of light aircraft took place at a meeting of the Technical Committee of the Institute in London on 21 April 1976. A personal view expressed by Mr. F. S. Stringer and comments by Mr. C. Powell and Professor A. N. Black are printed below.

Recent technical press disclosures have highlighted C.A.A. concern that the London Air Traffic Zone is being entered by unauthorized light aircraft, the infringements varying from minor boundary incursions to major crossings of the area. The pilots involved vary in experience, and in most if not all cases have been flying under VFR rules and out of radio contact with Air Traffic Control. It seems very probable that these pilots are lost, or at least very unsure of their position; the topographical relation of charts to places on the ground is becoming increasingly difficult to interpret due to the complexity of built-up areas, especially around the T.M.A.s. Not all aircraft carry VOR or ADF and the map and DR are the main navigational aids; some pilots are reluctant to call for radar assistance for a variety of reasons.
An American Omega Navigation Evaluation Programme 1975–1977
Authors: Reynolds P. R. J.
Published: November 2009

As a replacement for the Loran A systems installed on approximately fifty B-707/300 aircraft and to have this replacement fully operational by the end of 1977 only two options were available: the very well proven but relatively costly inertial systems and the almost totally unproven but potentially much less costly Omega. Economic considerations played a major role in this choice in view of the limited remaining useful life of the aircraft involved. The general object of the programme was to assess the acceptability of Omega as a pilot-operated substitute for Loran A in aircraft also equipped with dual doppler/computer navigation systems. Critical aspects of the use of Omega which were to be investigated were:

(i) the availability of adequate Omega signal coverage on a reasonably worldwide basis,

(ii) the normal in-lane accuracy of the Omega position output,

(iii) the in-lane stability of the Omega position output, i.e. susceptibility to ‘lane-slip’,

(iv) the reliability of the airborne Omega hardware,

(v) the operational suitability of the control/display units.
The Use of Omega at Sea
Authors: Riley A. P.
Published: November 2009

At first sight, it may seem inappropriate for an equipment manufacturer to present a resume of operation experience in the use of Omega at sea. The manufacturer is however a natural collection point for user experience and bad news travels fast while good news rarely travels at all!

The Omega transmitter network has improved considerably during the last year and with the exception of Australia all transmitters are now usable for navigation, with a typical reliability exceeding 99 per cent. This has only occurred in recent months, as previously coverage was only available in the northern hemisphere and it is users who frequently operate in this area who have become familiar with the system and gained confidence in its use.
A Survey of Marine Traffic in the Southern North Sea
Authors: Goodwin E. M. , Kemp J. F.
Published: November 2009

Over the past few years several papers have been written based on the results of surveys of marine traffic in different parts of the world. The general knowledge of the overall picture of the behaviour of ships at sea has increased considerably but there are still many aspects which need to be explored. One of the main fields of interest of the Marine Traffic Research Unit at the City of London Polytechnic is the use that mariners make of available sea room. For any particular area the navigational difficulties are going to vary considerably in situations where ships enter the area at different points, travelling indifferent directions, from situations in which the ships tend to keep to a number of defined routes through the area. If ships do tend to adopt a routing structure through an area, the next question of interest is how wide the various routes are, given no physical limitations for their width. The behaviour patterns may vary for different types of ship, and speed is another variable which may affect the situation. Answers to all these questions would be needed if one wanted to analyse the efficiency and safety aspects of marine traffic in an area.
A Method for Estimating the Voyage Distribution of Marine Traffic
Authors: Hara Kiyoshi
Published: November 2009

Various surveys have been carried out in narrow waters throughout the world and provide data on the traffic volume, traffic density, velocity distributions of ships, &c. Although these surveys certainly contribute to the safety of local navigation they do not give any information on traffic movements between terminal points in a marine traffic system. There are a few papers on voyage distribution based on traffic surveys, statistical reports or questionnaires to mariners and also a few based on radar observation, including one in Osaka Bay in Japan which was carried out by the traffic research group of the Kobe University of Mercantile Marine and Nautical Technical College.
Some Mathematical Aspects of Air Traffic Systems
Authors: Attwooll V. W.
Published: November 2009

In this paper, which was presented at a meeting of the Institute in London on 26 January 1977 with Group Captain H. L. Sheppard in the Chair, Mr. Attwooll, Head of the Air Traffic Studies Division at the Royal Aircraft Establishment, discusses the application of the theory of queues to air traffic control. He shows the importance of random perturbations due to late arrival of aircraft, and how traffic schedules in an airway network can best be adjusted to minimize delays due to congestion on certain routes. Much of this study was carried out on behalf of the Civil Aviation Authority but the opinions expressed do not necessarily reflect the policy either of the CAA or the Ministry of Defence
The Display of Navigational Data
Authors: Jones K. D. , Holder L. A.
Published: November 2009

The dissemination of navigational information is capable of several different interpretations and this paper will be concerned mainly with the display of information to the navigator of a modern merchant ship. It will not be concerned with the need for more navigational information in certain parts of the world, or the need for new sensors for critical areas of operation.

Most research papers on modern navigational systems launch into technical details without mention of the fundamental partner to the equipment—the man. Three quotations seem, however to be relevant. J. B. Carr says: ‘A frightening aspect of some of is he new problems is that they frequently defy solution by even the most skilled officers as the data available is in some cases changing with a speed and complexity that taxes the human mind beyond its limits.’
The Fully Automatic Radar Plotter in the Context of Some Past Collisions—II
Authors: Wylie F. J.
Published: November 2009

Captain Wylie reviews a further selection of collision cases in which more information might have been available on the bridge had the vessels concerned been equipped with modern automatic radar plotting equipment. The first five cases and introduction were published in the May 1977 issue of the Journal.

Case 6: Sitala and Niceto de Larrinaga, in fog in the English Channel at 19·32 on 23 September 1961. Admiralty Court, London, 1963; Mr. Justice Hewson found Niceto de Larrinaga 60 per cent to blame and Sitala 40 per cent (1963) 1 LR 205.
A Horizontal Radar Display
Authors: Hinsch Werner
Published: November 2009

The cause of an increasing number of ‘radar-assisted collisions’ is the inadequate link between the radar receiver and the human operator. In contrast to all other traffic situations, the seaborne radar display forces the navigator to assess an imminent danger of collision from a ‘bird's-eye view’. When navigating in reduced visibility those vessels are most dangerous which are detected on the radar screen as being on a reciprocal or nearly reciprocal course.

It is normally no problem for the navigator to assess the collision threat from a vessel he detects optically as being near his own course line; the heading of the opponent clearly indicates the situation. A head-on situation indicates the necessity to take evasive action and the aspect of the opponent's port (or starboard) bow is left (right) indication for a left (right) change of bearing. The collision danger arising from any other target located in good visibility, and not near one's own heading line, can be assessed by repeatedly measuring or judging the target's bearing. Thus two different principles are applied to determine the threat of collision:

(i) With direct vision, by assessing the movements of approaching vessels in a horizontal direction,

(ii) With radar, by assessing the future passing distances from the plan view of the traffic situation.
The First Navigation of Torres Strait
Authors: Hilder Brett
Published: November 2009

The voyage of Luis Baez de Torres in 1606 resulted in the discovery of the whole southern coast of New Guinea, and of the existence of a strait between Australia and New Guinea. These great geographical results were hidden from the world, and even from the Spanish realms, so completely that sufficient data on the voyage for general study has not been available until recently. The very brief report by Torres to the King was not found, copied, translated and published until 1806, exactly 200 years after the voyage; the four charts made during the voyage were published in 1878, and the long narrative by Prado was found by chance in London, translated, and published in 1929. Hundreds of documents of secondary importance were collated and published in 1965, but owing to the habit of historical writers of using older ‘authorities’ instead of original sources, many fallacies regarding the voyage have been perpetuated to the present day, and no doubt will be in the future. The present writer, working from photostat copies of the original reports and charts, has plotted the track of Torres' two vessels from island to island and point to point by interpreting the records, by navigational deduction and from a long experience of navigating ships through the very waters traversed by Torres. He has also made sketch surveys of uncharted areas and has studied the various rare charts, maps and globes compiled by different cartographers between 161 3 and 1700 from the three or four coastal charts drawn by Prado but missing from the archives since soon after the voyage.

The principal conclusion of this study is that Torres used Endeavour Strait to get clear of the innumerable islands and reefs which blocked his course to the west and was therefore in sight of the Australian coast for many days, a finding contested by several previous writers.
The Navigational Requirements for Ocean Racing
Authors: Phelan C. N.
Published: November 2009

In discussing the navigational requirements for any vessel (including yachts) it must be remembered that there are two co-related areas for discussion: equipment and knowledge. Of these two the requirement for knowledge is of greater importance. Knowledge implies the ability to use the apparatus at one's disposal to the maximum efficiency in order to obtain the information one requires and, of equal importance, the ability to assess the validity of the information so obtained, and thereafter to use it in the most beneficial manner in the prevailing circumstances.
Radio Aids to Navigation for Yachts
Authors: Gatehouse R. N. B.
Published: November 2009

Radio aids are making a substantial contribution to the safety of yacht navigation, mainly by enabling off-lying dangers to be avoided when making landfall in conditions of poor visibility or overcast sky. The ability to obtain fixes of sufficient accuracy to keep clear of shipping lanes in fog is another important safety factor.

The use of hyperbolic aids, of which Loran is one, is expressly banned in ocean racing both in the U.S.A. (except in the Bermuda race) and the U.K., on account of the high price of the receivers and the advantage they might confer on those who can afford to buy or hire them. Table I shows the systems which are available in British waters, the types of error to which they are prone and some typical accuracy figures obtainable at sea. It is of particular interest to note that the accuracy of the hyperbolic aids, VOR and Consol is unaffected by the motion or attitude of the vessel, or by its metallic structures and rigging; d.f. is subject to errors from all three of these causes and all the systems except VOR are subject to the night-time sky-wave error.
The Use of Radar Reflectors and Transponders by Sailing Craft
Authors: Harrison A.
Published: November 2009

Two devices may be used to enhance the radar echo from a small craft or a buoy. A radar reflector will send back to the radar nearly all the transmitted power it receives, instead of scattering it. It is like a very small heliograph mirror reflecting sunlight, which is as easily seen as a large white sail. A transponder on the other hand is an active electronic device which, when it detects the transmitted radar pulse, immediately transmits its own identifying signal back to the radar. The appearance at the radar display can be seen in Fig. 1 (North is at the top and the range rings are at 1 mile intervals). The transponder was in a small boat at 2·8 miles range on 162°, its response being the Morse letter Y. No. 1 Sea Reach buoy with a reflector on it is visible at 6 miles on 115°.
The Danger of Collision with Merchant Vessels
Authors: Kemp J. F.
Published: November 2009

Some Implications of the New Collision Regulations. In Rule 6 the discussion of what constitutes a ‘safe speed’, paragraph (b) (iv) states that ‘the possibility that small vessels, ice and other floating objects may not be detected by radar at an adequate distance’ is one of the factors which should be taken into account. Leaving aside the question of how the new term ‘safe speed’ differs from the old ‘moderate speed’ this is not a fundamental change, although the provision appears in a different place and with different emphasis in the new rules. It is a provision which ought to be treated more conscientiously by many mariners since, for example, it has been observed that the mean speed of ships through the Dover Strait is about 12 knots and that this does not appear to be significantly reduced when visibility decreases.
Safety Problems for the Single Hander
Authors: Knox-Johnston Robin
Published: November 2009

Safety problems for a single-hander fall into two basic categories: those affecting the single-hander and those that affect other people. The most obvious difference between sailing in, say, R.O.R.C. races and on one's own is that there is no back-up for the single hander when some particular task such as a sail change has to be carried out. Whereas on a modern ocean racer most jobs can, and indeed have to, be swamped with men in order to achieve not necessarily the most efficient result but the fastest result, for the single-hander the job has to be much more carefully thought out so that at no time does he place himself in the position where a piece of gear or equipment can lose itself because he is elsewhere.
A Case of Random Collision Probabilities
Authors: Goodwin E. M. , Kemp J. F.
Published: November 2009

In the contribution to the joint Royal Institute of Navigation/Royal Ocean Racing Club meeting on Safety of Navigation under Sail (p. 467), an expression was quoted for the random probability of collision in the case of a large, relatively fast ship passing through a concentration of smaller craft. It was not appropriate to discuss the derivation of the expression in the particular circumstances of the meeting but the methodology may be of some general interest and it is therefore outlined in this note.
Inertial Navigation
Authors: Powell Claud
Published: November 2009

The following letter to Nature, dated 24 April 1873, might make an appropriate sequel to ‘The history of inertial navigation’ by W. Wrigley in the January issue of the Journal. As well as containing some interesting speculation about animal navigation, which we seem no nearer resolving a century later, the letter includes an introduction to the idea of inertial navigation that it would be difficult to improve upon even today.
The Role of Lighting in Aids to Marine Navigation
Authors: Clissold P.
Published: November 2009

L. G. Reynold's interesting article (Journal30, 108) gives rise to a question. Why, on the new charts is the light range given as the luminous or nominal range, instead of, as formerly, the geographical range (for a height of eye of 15 ft)? This, from the point of view of the practical navigator, seems a retrograde step for we can no longer see from a glance at the chart the approximate range at which we may expect to sight a light. The luminous range is almost always greater than the geographical range and reference must be made to the Geographical Range Table in the Admiralty List of Lights to find out what the latter will be.
A Polar Compass
Authors: Wolff F. G.
Published: November 2009

The basic premise of compass adjusting (that is compensation aboard ship for magnetic fields caused by the vessel itself and the determination of residual deviation) is that a reference direction must be available during the operation. Normally visual ranges or the azimuth of a celestial body—usually the Sun—are used, but in some areas and climates reduced visibility often does not permit the use of either. Compass adjusters are frequently driven in desperation to use gyro-compass, radar, or radio bearings—with highly speculative results as the errors of these instruments are generally unknown, and fairly large compared to the accuracy required of the magnetic standard compass (± ½°) which is the primary direction standard aboard ship.
The Conception and Development of Weir's Diagram
Authors: Cotter Charles H.
Published: November 2009

Just a century ago, in 1876, Patrick Weir, an officer of a vessel trading between London and Australia, conceived the idea of a diagram that might facilitate finding the Sun's true azimuth for the purpose of checking the magnetic compass. Some thirteen, years later Captain Weir's Diagram was the subject of a paper communicated by Sir William Thomson (later Lord Kelvin) to the Royal Society of Edinburgh. In his paper Weir outlined the train of reasoning by which he succeeded in constructing a novel diagram which was described by Professor P. G. Tait as ‘a singularly elegant construction which, not only puts in a new and attractive light one of the most awkward of the problems of spherical trigonometry, but it practically gives in a single-page diagram the whole content of the two volumes of Burdwood's Azimuth Tables’. Tait also remarked that the method supplied an interesting graphical plane construction of a function of three independent variables.
Edmund Gunter (1581–1626)
Authors: Cotter Charles H.
Published: November 2009

The year 1981 marks the fourth centenary of the birth of Edmund Gunter who, during his relatively short life, played a dominant role in England in the advancement of navigation. Born in Hertfordshire, of Welsh parentage, Gunter was educated at Westminster School before entering Christchurch College, Oxford, where he graduated BA in 1603; MA in 1606; and BD in 1615, in which year he was presented to the living at St George's, Southwark.

As early as 1603 Gunter had written an account of a ‘New Projection of the Sphere’ which was circulated in manuscript among some of his mathematical acquaintances. This appears to have gained for him the friendship of Henry Briggs, the first Gresham Professor of Geometry and a brilliant mathematician best known for having been first to suggest a table of logarithms to base 10 – ‘common logarithms’, as they are now known.
Marine Traffic off the Coast of East Anglia
Authors: Chalk R. F. , Dare S. C. , Lewison G. R. G.
Published: November 2009

It has for some years now almost been folklore that the marine traffic situation in the Dover Strait is one of great potential danger. Very considerable efforts have been made to alleviate the situation. There is a complete traffic separation scheme (the first in the world), there is continuous radar surveillance both from England and France, there are routine broadcasts on v.h.f. to warn mariners of any navigational problems, and there is now a system whereby certain ships report-in. Concurrently with all this activity, the accident rate has dropped significantly over the last decade, especially in fog, and it is a reasonable inference that the reduction in the number and severity of accidents is attributable to this activity.

But patterns of navigation change, and it is necessary for marine administrators to be aware of problem areas as or before they arise so that marine management measures can be introduced when appropriate. Factors to be taken into account are the volume and characteristics of the traffic, the difficulty of navigation and the accident record. One of us has drawn attention to the traffic situation off East Anglia and suggested that a prima facie case for some remedial measures had been made. This paper examines the available evidence in more detail.

First, an account is given of the accident record in the area under consideration (Figs 1, 2) over the last 10 years. Both the numbers and severity of collisions and strandings are discussed.
Were Compasses used in Antiquity?
Authors: May W. E.
Published: November 2009

In the title to this paper I have deliberately used the plural, for I do not think it possible that the compass was only invented in one country and knowledge of it transmitted from there to other parts of the world. It is much more likely that the possibilities of its use, not necessarily for purposes of marine navigation, were discovered in several parts of the world, that some who knew of it transmitted it to their neighbours, but that in some areas the original knowledge was lost again. Of course such inventions may have had forms very different from the compass as finally used.

The first definite European account of the compass is contained in the writings of Alexander Neckam (1157–1217), about A.D. 1187. InDe Utensilibushe wrote: ‘Qui ergo munitam vult habere navem…habeat etiam acum jaculo suppositam; rotabitur enim et circumvolvetur acus, donec cuspis acus respiciat orientem sicque comprehendunt quo tendere debeant nautae cum cynosura latet in aeris turbatione.’ The translation of this which I accept is as follows: ‘Therefore he who wants to have a well-equipped ship…let him also have a needle placed under a dart; for the needle will rotate until the point of the needle looks towards the East, and thus sailors perceive in which direction they ought to go, when the Little Bear is hidden in disturbed weather’. It has been suggested that in this passage ‘donec cuspis jaculi respeciat’ was probably intended for ‘donee cuspis acus respiciat’.
The Relation Between Aircraft Fuel Reserves and Navigation
Authors: Attwooll V. W.
Published: November 2009

This paper was presented at a meeting of the Institute in London on 21 January 1981 with W. H. McKinlay in the Chair. The views expressed do not necessarily represent CAA policy, but Mr Attwooll discusses the derivation of fuel-uplift requirements from considerations of safety and regularity of the flight, using additional information on the probability of various adverse contingencies such as headwind or ATC delay. Methods of safely reducing fuel reserve requirements are discussed, including improvements in navigation and the on-board decision-making process.
The New-Look Admiralty Chart
Authors: Magee G. A.
Published: November 2009

The new-look Admiralty chart is no longer novel; the first metric chart was in fact published ten years ago and there are now over 700 metric charts in our standard series, representing over 20 per cent of the total currently in publication. Their impact is disproportionate to their numbers however, since many metric charts figure among those most used, and there is now about a one-in-three chance that any Admiralty chart being employed is a metric one. Popular charts tend to be much-corrected charts and in fact a third of the new editions and a third of the paste-on blocks that we issued last year were to metric charts. Moreover, we now publish a hundred new charts a year and hope that this figure will be maintained.
The Introduction of IALA Maritime Buoyage System A
Authors: Pielou F. A.
Published: November 2009

In the January 1977 issue of this Journal an article ‘The new buoyage system’ by the Hydrographer of the Navy was one of the many steps taken during the past two years to explain to chart users what IALA System A is all about. Newspapers, magazines, schools of navigation, yachting clubs and commercial printers have all helped to spread the gospel. There are on the market a variety of booklets, wall charts, plastic models, cassette teaching aids and films. The new symbols used to portray the details on the charts can be found in Navigation Publication NP735, available from Admiralty chart agents.
International Charts
Authors: Newson D. W.
Published: November 2009

The 1967 Conference of the International Hydrographic Organization (IHO) set up a six-nation Commission to obtain an agreed specification for a series of small-scale international charts, with a view to sharing production among a number of hydrographic offices on a regional basis. The intention was that any office could reprint any or all of the sheets, and make modifications for language or to obtain conformity with its own national series.
Progress in Nautical Chart Automation
Authors: Murt G. E.
Published: November 2009

For the past few years it has been technically possible to produce digital versions of charts and maps but the manual digitizing of very large amounts of irregular line and point data is both slow and prone to error; the benefits of automation in this field are less clear-cut than in the production of computed linework such as borders and lattices. Semi-automatic line digitizing equipment is just coming on to the market and this will undoubtedly speed up data acquisition rates, particularly where good-quality line work is being digitized. Nevertheless some mapping authorities (e.g. the United Kingdom Ordnance Survey) have already made considerable progress in the digitizing of maps, both to provide input for the automated fair-drawing of these maps on one or more scales and to supply digital versions of selected features (e.g. road and boundary patterns, frontings of buildings) to prospective customers, such as the public utility group—gas, electricity, telephone and drainage authorities.
Digital Information and Chart Users
Authors: Holder L. A.
Published: November 2009

The introduction of digital computers in hydrographic surveying has led to a decrease in routine work and an increase in time for decision making. In merchant ships there are likely to be similar benefits, but there are many facets to the introduction of digital computers. The main criterion, if the introduction is to be a success, must be a considerable improvement in the performance of men and equipment when compared with the additional cost of a revised system, including training in its use. There are two main decision-making phases in navigation—voyage planning and watchkeeping; we must therefore consider the assistance that electronic data processing could give to the navigator in providing data on which plans can be evaluated, progress monitored and decisions made.
AThy1-CFP DBA/2J mouse line with cyan fluorescent protein expression in retinal ganglion cells
Authors: RAYMOND IONA D. , POOL ANGELA L. , VILA ALEJANDRO , BRECHA NICHOLAS C.
Published: November 2009

A DBA/2J (D2) transgenic mouse line with cyan fluorescent protein (CFP) reporter expression in ganglion cells was developed for the analysis of ganglion cells during progressive glaucoma. TheThy1-CFP D2 (CFP-D2) line was created by congenically breeding the D2 line, which develops pigmentary glaucoma, and theThy1-CFP line, which expresses CFP in ganglion cells. Microsatellite marker analysis of CFP-D2 progeny verified the genetic inclusion of the D2isaandipdloci. Specific mutations within these loci lead to dysfunctional melanosomal proteins and glaucomatous phenotype in D2 mice. Polymerase chain reaction analysis confirmed the inclusion of theThy1-CFP transgene. CFP-fluorescent ganglion cells, 6–20μm in diameter, were distributed in all retinal regions, CFP processes were throughout the inner plexiform layer, and CFP-fluorescent axons were in the fiber layer and optic nerve head. Immunohistochemistry with antibodies to ganglion cell markers NF-L, NeuN, Brn3a, and SMI32 was used to confirm CFP expression in ganglion cells. Immunohistochemistry with antibodies to amacrine cell markers HPC-1 and ChAT was used to confirm weak CFP expression in cholinergic amacrine cells. CFP-D2 mice developed a glaucomatous phenotype, including iris disease, ganglion cell loss, attrition of the fiber layer, and elevated intraocular pressure. A CFP-D2 transgenic line with CFP-expressing ganglion cells was developed, which has (1) a predominantly D2 genetic background, (2) CFP-expressing ganglion cells, and (3) age-related progressive glaucoma. This line will be of value for experimental studies investigating ganglion cells and their axonsin vivoandin vitroduring the progressive development of glaucoma.
A neo-Weberian approach to religion in international politics
Authors: Lynch Cecelia
Published: November 2009

Current approaches for understanding and analyzing religion in international politics insufficiently incorporate the role of ethics in the practices of religious actors. Primordialist approaches essentialize religion, instrumental approaches consider it to be an epiphenomenon, and cosmopolitan approachesa prioridowngrade alternative ethical constructs as insufficiently universalist. An approach to religion that begins with a constitutive understanding of religious belief and economic, social, and political practice as outlined in Weber’sSociology of Religion, is more helpful. However, because Weber’s method insufficiently addresses ethical intentionality, the ‘neo-Weberian’ approach I advance here incorporates the concepts of ‘common good’ and ‘popular casuistry’ into socio-historical contextualization. This approach provides a way to understand and theorize how religious adherents connect religious guidelines to moral action that avoids the essentialization of religion which is often characteristic of other perspectives.
The politics of the philosophy of science
Authors: Kurki Milja
Published: November 2009

Monteiro and Ruby (2009) argue that International Relations (IR) scholars should look to adopt a more ‘tentative attitude’ towards the philosophy of science (PoS) frameworks in IR. This is an attractive and timely call for more open-minded PoS argumentation in the field. Yet, the logic of Monteiro and Ruby’s argument is not (rather characteristically of PoS debates) infallible. As other commentaries in this forum show, it is not self-evident that Monteiro and Ruby’s account is ‘post-foundational’, or that it is premised on an accurate reading of existing PoS positions in IR. However, I do not here wish to elaborate further on the critiques that could be made of the internal coherence of Monteiro and Ruby’s argumentation or their reading of core philosophical schools. Instead, I want to discuss a different kind of an issue raised by Monteiro and Ruby’s intervention: their treatment of the interaction of political forms of argumentation and PoS debates.
ICRC operational security: staff safety in armed conflict and internal violence
Authors: Brugger Patrick
Published: November 2009

Humanitarian work, especially in conflict areas, has become more dangerous and every humanitarian organization is affected by serious security problems, constituting a threat to their staff and hampering much-needed activities on behalf of the victims of armed conflicts and other situations of collective armed violence. The article outlines the general approach of the ICRC to security issues and describes the pillars of the security policy it has adopted in the field to protect its operational staff.
The 2006–2007 Kuril Islands great earthquake sequence
Authors: Lay Thorne , Kanamori Hiroo , Ammon Charles J. , Hutko Alexander R. , Furlong Kevin , Rivera Luis
Published: November 2009

The southwestern half of a ∼500 km long seismic gap in the central Kuril Island arc subduction zone experienced two great earthquakes with extensive preshock and aftershock sequences in late 2006 to early 2007. The nature of seismic coupling in the gap had been uncertain due to the limited historical record of prior large events and the presence of distinctive upper plate, trench and outer rise structures relative to adjacent regions along the arc that have experienced repeated great interplate earthquakes in the last few centuries. The intraplate region seaward of the seismic gap had several shallow compressional events during the preceding decades (notably an MS 7.2 event on 16 March 1963), leading to speculation that the interplate fault was seismically coupled. This issue was partly resolved by failure of the shallow portion of the interplate megathrust in an MW = 8.3 thrust event on 15 November 2006. This event ruptured ∼250 km along the seismic gap, just northeast of the great 1963 Kuril Island (Mw = 8.5) earthquake rupture zone. Within minutes of the thrust event, intense earthquake activity commenced beneath the outer wall of the trench seaward of the interplate rupture, with the larger events having normal‐faulting mechanisms. An unusual double band of interplate and intraplate aftershocks developed. On 13 January 2007, an MW = 8.1 extensional earthquake ruptured within the Pacific plate beneath the seaward edge of the Kuril trench. This event is the third largest normal‐faulting earthquake seaward of a subduction zone on record, and its rupture zone extended to at least 33 km depth and paralleled most of the length of the 2006 rupture. The 13 January 2007 event produced stronger shaking in Japan than the larger thrust event, as a consequence of higher short‐period energy radiation from the source. The great event aftershock sequences were dominated by the expected faulting geometries; thrust faulting for the 2006 rupture zone, and normal faulting for the 2007 rupture zone. A large intraplate compressional event occurred on 15 January 2009 (Mw = 7.4) near 45 km depth, below the rupture zone of the 2007 event and in the vicinity of the 16 March 1963 compressional event. The fault geometry, rupture process and slip distributions of the two great events are estimated using very broadband teleseismic body and surface wave observations. The occurrence of the thrust event in the shallowest portion of the interplate fault in a region with a paucity of large thrust events at greater depths suggests that the event removed most of the slip deficit on this portion of the interplate fault. This great earthquake doublet demonstrates the heightened seismic hazard posed by induced intraplate faulting following large interplate thrust events. Future seismic failure of the remainder of the seismic gap appears viable, with the northeastern region that has also experienced compressional activity seaward of the megathrust warranting particular attention.
Particle resuspension in the Columbia River plume near field
Authors: Spahn Emily Y. , Horner‐Devine Alexander R. , Nash Jonathan D. , Jay David A. , Kilcher Levi
Published: November 2009

Measurements of suspended sediment concentration, velocity, salinity, and turbulent microscale shear in the near‐field region of the Columbia River plume are used to investigate the mechanisms of sediment resuspension and entrainment into the plume. An east‐west transect was occupied during spring and neap tide periods in August 2005 and May 2006, corresponding to low and high river discharge conditions, respectively. During the high‐discharge period the plume is decoupled from the bottom, and fine sediment resuspended from the bottom does not leave the benthic boundary layer. The primary modes of sediment transport associated with the plume are advection of sediment from the estuary and removal of sediment from the plume by gravitational settling and turbulent mixing. In contrast, the plume is much less stratified during low‐discharge conditions, and large resuspension events are observed that entrained sediment through the water column and into the plume. Our measurements indicate that two factors control the magnitude and timing of sediment resuspension and entrainment: the supply of fine sediment on the seabed and the relative influence of tidal turbulence compared with buoyancy input from the river. The latter is quantified in terms of the estuary Richardson number RiE. The magnitude of vertical turbulent sediment flux is correlated with RiE during the low‐flow period when there is a sufficient supply of bottom sediment in the near‐field region. Such sediment resuspension may be an important mechanism for the delivery of bioavailable micronutrients to the plume during the summer.
Probabilistic tsunami hazard assessment at Seaside, Oregon, for near‐ and far‐field seismic sources
Authors: González F. I. , Geist E. L. , Jaffe B. , Kânoğlu U. , Mofjeld H. , Synolakis C. E. , Titov V. V. , Arcas D. , Bellomo D. , Carlton D. , Horning T. , Johnson J. , Newman J. , Parsons T. , Peters R. , Peterson C. , Priest G. , Venturato A. , Weber J. , Wong F. , Yalciner A.
Published: November 2009

The first probabilistic tsunami flooding maps have been developed. The methodology, called probabilistic tsunami hazard assessment (PTHA), integrates tsunami inundation modeling with methods of probabilistic seismic hazard assessment (PSHA). Application of the methodology to Seaside, Oregon, has yielded estimates of the spatial distribution of 100‐ and 500‐year maximum tsunami amplitudes, i.e., amplitudes with 1% and 0.2% annual probability of exceedance. The 100‐year tsunami is generated most frequently by far‐field sources in the Alaska‐Aleutian Subduction Zone and is characterized by maximum amplitudes that do not exceed 4 m, with an inland extent of less than 500 m. In contrast, the 500‐year tsunami is dominated by local sources in the Cascadia Subduction Zone and is characterized by maximum amplitudes in excess of 10 m and an inland extent of more than 1 km. The primary sources of uncertainty in these results include those associated with interevent time estimates, modeling of background sea level, and accounting for temporal changes in bathymetry and topography. Nonetheless, PTHA represents an important contribution to tsunami hazard assessment techniques; viewed in the broader context of risk analysis, PTHA provides a method for quantifying estimates of the likelihood and severity of the tsunami hazard, which can then be combined with vulnerability and exposure to yield estimates of tsunami risk.
Fate of SO2 in the ancient Martian atmosphere: Implications for transient greenhouse warming
Authors: Johnson Sarah Stewart , Pavlov Alexander A. , Mischna Michael A.
Published: November 2009

There is increasing evidence that sulfur played an important role on early Mars. Sulfur is distributed ubiquitously on the Martian surface, and sulfur in Martian meteorites carries the signature of atmospheric interactions. Recent work suggests that the radiative properties of sulfur volatiles that were degassed into the Martian atmosphere may have caused a greenhouse effect early in the planet's history. It remains unclear, however, over what timescales warming from sulfur volatiles would have persisted, and consequently how significant this warming may have been. While most photochemistry research to date has concentrated on current Martian conditions, the ancient Martian atmosphere was thicker, warmer, and more reducing than the current regime. Here we investigate sulfur photochemistry in a 500 mb ancient Martian atmosphere. After adapting a model used to study sulfur photochemistry on Earth during the Archean, we find a short lifetime for SO2 in the current Martian atmosphere, similar to results of other photochemical studies. However, our simulations suggest that moderate mixing ratios of SO2 (10−8 ≤ f(SO2) ≤ 10−6) could have persisted in the ancient Martian atmosphere for hundreds of years, generating short but potent warming events following episodes of volcanic activity.
Interannual variability of the carbon balance of three different‐aged Douglas‐fir stands in the Pacific Northwest
Authors: Krishnan Praveena , Black T. Andrew , Jassal Rachhpal S. , Chen Baozhang , Nesic Zoran
Published: November 2009

The seasonal and interannual variability of gross ecosystem photosynthesis (Pg) and ecosystem respiration (Re), and their relationships to environmental variables and stand characteristics were used to explain the variation of eddy‐covariance‐measured net ecosystem productivity (FNEP) of three different‐aged Douglas‐fir stands located on the east coast of Vancouver Island in British Columbia, Canada. During the 9‐year period, 1998–2006, which included a strong El Niño/La Niña event, the near‐end‐of‐rotation stand (DF49, 57 years old in 2006) was a moderate carbon (C) sink for CO2 with annual FNEP ranging from 267 to 410 g C m−2 yr−1 (mean ± SD, 357 ± 51 g C m−2 yr−1). The pole/sapling stand (HDF88, 18 years old in 2006) was a weak C source (FNEP = −64 ± 75 g C m−2 yr−1), and the recently harvested stand (HDF00, 6 years old in 2006) was a large C source (FNEP = −515 ± 88 g C m−2 yr−1) during 2002–2006. Irrespective of stand age, all sites responded quite similarly to changes in environmental variables during each year. Daily total values of Pg and Re were highest in July–August in all three stands, while daily FNEP peaked during April–June at DF49, May–June at HDF88, and June–July at HDF00. Reductions in root‐zone soil water content decreased both Pg and Re especially during the dry period from May to September, and this effect was more pronounced in the younger stands. Evapotranspiration and dry‐foliage surface conductance also decreased with decreasing root‐zone soil water content whereas water use efficiency appeared to be conservative, especially at DF49. Increasing spring temperature had a positive effect on annual Pg and Re but caused a slight decrease in annual FNEP. During the summer to autumn transition period, increases in soil water content resulted in a greater increase in Re than Pg causing a reduction in FNEP. The interannual variation in the C balance was determined mainly by the interannual variation in Re for the near‐end‐of‐rotation stand and Pg for the two younger stands. The results indicate that regardless of the stand age, interannual variability in the C balance was mainly determined by year‐to‐year variability in spring temperature and water availability in late summer.
Dominant role by vertical wind shear in regulating aerosol effects on deep convective clouds
Authors: Fan Jiwen , Yuan Tianle , Comstock Jennifer M. , Ghan Steven , Khain Alexander , Leung L. Ruby , Li Zhanqing , Martins Vanderlei J. , Ovchinnikov Mikhail
Published: November 2009

Aerosol‐cloud interaction is recognized as one of the key factors influencing cloud properties and precipitation regimes across local, regional, and global scales and remains one of the largest uncertainties in understanding and projecting future climate changes. Deep convective clouds (DCCs) play a crucial role in the general circulation, energy balance, and hydrological cycle of our climate system. The complex aerosol‐DCC interactions continue to be puzzling as more “aerosol effects” unfold, and systematic assessment of such effects is lacking. Here we systematically assess the aerosol effects on isolated DCCs based on cloud‐resolving model simulations with spectral bin cloud microphysics. We find a dominant role of vertical wind shear in regulating aerosol effects on isolated DCCs, i.e., vertical wind shear qualitatively determines whether aerosols suppress or enhance convective strength. Increasing aerosols always suppresses convection under strong wind shear and invigorates convection under weak wind shear until this effect saturates at an optimal aerosol loading. We also found that the decreasing rate of convective strength is greater in the humid air than that in the dry air when wind shear is strong. Our findings may resolve some of the seemingly contradictory results among past studies by considering the dominant effect of wind shear. Our results can provide the insights to better parameterize aerosol effects on convection by adding the factor of wind shear to the entrainment term, which could reduce uncertainties associated with aerosol effects on climate forcing.
Breakdown of potential vorticity–based equivalent latitude as a vortex‐centered coordinate in the polar winter mesosphere
Authors: Harvey V. Lynn , Randall Cora E. , Hitchman Matthew H.
Published: November 2009

Potential vorticity (PV) and stream function (ψ) are useful vortex‐centered coordinates for studying the winter stratosphere, since both exhibit monotonic relationships with tracer constituents. At each isentropic level in the stratosphere and mesosphere, ψ varies monotonically normal to the jet axis and to tracer contours, and can thus be considered vortex‐centered. In the stratosphere, PV is anticorrelated with ψ and is also vortex‐centered. We show that, contrary to this, above ∼3000 K (∼60 km) the PV‐ψ anticorrelation breaks down up to 80% of the time. Over five years of Goddard Earth Observing System analyses are used to depict the seasonal and spatial variation of the relationship between PV and ψ. The deviation of PV from a vortex‐centered coordinate is estimated by calculating differences between the mean latitude of the highest PV band and the most polar mean latitude for any PV band in the hemisphere. If PV is anticorrelated with ψ, and thus vortex centered, these differences should be small. In both winter hemispheres, latitude differences are less than 5° below 55 km but exceed 15° above 60 km (∼0.5 hPa, ∼3000 K). In the mesosphere, regions of small PV are usually found in the vortex core and the largest PV values are located along the subtropical jet. The relationship between PV and ψ in the polar lower mesosphere is interpreted in the context of the gravity wave driven warm anomaly, the associated wave breaking regime, and local static stability anomalies which affect PV much more than ψ.