Recent sio_reference items

"It's the Water that Makes you Drunk" - A Celebration in Geophysics and Oceanography - 1982, In Honor of Walter Munk on his 65th Birthday, October 19, 1982

Fri, 15 Oct 2021 00:00:00 +0000

The title quote, which was recounted during these birthday festivities, derives from a dinner during Walter's earth rotation days. W. Markowitz of the U.S. Naval Observatory told of the logical scientist who set out to determine the cause of drunkenness. On successive days he consumed large quantities of scotch and water, bourbon and water, and vodka and water. Becoming drunk in each case he concluded that the water was responsible. Markowitz went on to find a parallel in the authorship of anumber of then-recent papers on the rotation of the earth (e.g. 49, 60, 72 in the bibliography), singling out Walter as the common ingredient in this infiltration of geophysicists into what had been the domain of astronomers.

Submarine Topography of the Continental Slope of the Northwest Gulf of Mexico

Fri, 15 Oct 2021 00:00:00 +0000

A chart of the continental slope of the northwest Gulf of Mexico, contoured at an interval ot 50 fathoms, reveals an irregular topography of high relief. The striking basins, ridges and trough-like valleys of the slope, and escarpment are described. Slumping, folding, and faulting are suggested as the cause of the slope topography, and the escarpment is interpreted as a fault zone separating the stable deep sea basin from the unstable elope area. Evidence from foraminiferal fauna distribution in cores is cited in support of slumping.

The Research Ship HORIZON

Thu, 18 Feb 2021 00:00:00 +0000

The R/V Horizon was one of the first of the post World War II oceanographic research vessels, and one of the most famous. It is a rare senior oceanographer anywhere in the world who has not at least seen the ship. The same is true of the RussianVityaz and Ob, the French Calypso, and the American Atlantis and Vema. Many of these research vessels were converted for ocean studies: Calypso was a former Royal Navy minesweeper; Vityaz was a German banana boat acquired in war reparation payments; Horizon was originally a small Navy tug.

Sediment Data Bank Users Handbook

Fri, 22 May 2015 00:00:00 +0000

Sediment Data Bank Users Handbook

Index to Sediment Samples from East and Southeast Asia Seas

Wed, 20 May 2015 00:00:00 +0000

Index to Sediment Samples from East and Southeast Asia Seas

Sediment Data Bank Coding Instructions

Wed, 20 May 2015 00:00:00 +0000

Sediment Data Bank Coding Instructions

An adaptation of the method of probability analysis to psychophysical threshold data

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 60-47. The objective of this development is to adapt the methods of probit analysis to automatic desk calculator computation by personnel relatively untrained and unoriented in probability techniques and in methods of psychophysical determination of visual thresholds.

A computer treatment of radiative transfer on a cubic-lattice (plane sources)

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 60-46. The purpose of this report is to study the numerical application of one such technique. This technique is called discrete-space radiative transfer theory.

Submarine visibility and related ambient light studies

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 63-32. The major effort which was undertaken during the one-year period of the contract was to provide requested support for two field operations whose purpose was the study of the visibility of submarines from aircraft. Neither of these operations were successful in providing the primary information which was being sought due mostly to the vagaries of the weather and the Cuban blockade. Recommendations are given for a .plan for a future operation with more carefully controlled conditions and more restricted and specific objectives.

The index of refraction of seawater

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 76-1. ft smoothly varying and internally self-consistent set of tables of the index of refraction of seawater with respect to air are presented. The dependence of the index on salinity (0 to 43°/00), temperature (0 to 30°C), wavelength(400 to 700 nm) and pressure (0 to 1100 kg/cm2 gage) has been fully covered. The relevant literature from prior to 1900 through the present has been extensively reviewed. Various comparisons between indices obtained from these sources and the tables presented have been performed suggesting an overall accuracy of the tabulated index values of about 3 x 10~s at atmospheric pressure and 1 x 10~4 at higher pressures. The extreme values encountered were 1.32921 and 1.36844, while the average slopes of the index surface, over the range of the variables considered, are An/As « 0.009/43°/00, An /At« - 0.002/30°C, An/AA« -0.013/300 nm, An/Ap« 0.015/1100 kg/cm2. Three dimensional diagrams provide complete views of the index of refraction surface.The...

Measurements of the transmission of light from an underwater source having variable beam spread

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 60-57. The present report describes underwater measurements of thetransmission of light from a submerged source of variable beam-spread.o Angular beam-widths down to 20 were used.

A study of the factors affecting the sighting of surface vessels from aircraft

Thu, 20 Jun 2013 00:00:00 +0000

SIO Refrence 62-13. A collection of 3,465 detailed reports of sightings of surface vessels from aircraft of the U. S. Coast Guard are analyzed by pro-bit analysis to determine visual thresholds and measures of variance of the thresholds. Each of seventeen conditions affecting the sighting range is studied separately to determine its effect. Empirical functions are developed to describe the threshold effects of e~ch of the eleven following oonditions in decreasing order of importance: (1) meteorological visibility, (2) altitude of aircraft, (3) ship size, (4) height of major swells, (5) cloud cover, (6) wind velocity, (7) relative bearing of target, (8) sun altitude, (9) relative bearing of sun, (10) wake size, and (11) wind azimuth. Thresholds are developed for the six following discrete conditions in decreasing order of importance: (12) visual aid, (13) range determination method, (H) type of observing unit, (15) time of day, (16) observer, (17) station. In each case, tables...

Contrast thresholds as a function of retinal position and target size for the light-adapted eye

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 61-10. Binocular visual thresholds for targets of several sizes and occupying various positions in the visual field have been measured at photopic adaptation luminance. Circular targets of positive contrast were presented for 0.33 second, chosen as a duration typical of the dwell times used in normal visual search procedures. Four young male observers with normal vision were used as subjects for the experiment. The data, based on approximately 80,000 observations, exhibit the dependence of the visual contrast threshold upon target size and position. The findings of the study differ, as anticipated, from other data which relate to the case of very brief (10 millisecond) target flashes, and are believed more suitable than the latter for the construction of visibility lobes used in the prediction of sighting ranges. The roles of various factors such as retinal neuroanatomy and eye-movement have been suggested, and intercomparison between studies has been attempted in...

Atmospheric optical measurements during high altitude balloon flight, Part III, Sky radiances in the 400 to 500 millimicron region

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 61-2. Certain optical measurements of the atmosphere were made by the Visibility Laboratory of the University of California, San Diego, 21 June 1958 over central Minnesota. Data were recorded from daybreak to midmorning during the time four balloons carrying optical instrumentation from the Geophysics Research Directorate, Air Force Research Division, Bedford,Massachusetts, were floating at higher altitudes.

Visual contrast thresholds for large targets. Part I, the case of low adapting luminances

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 60-25. The contrast sensitivity of the human observer has been systematically investigated at a wide range of target sizes and background luminances. The present study was undertaken in an attempt to extend to the case of targets subtending more than 360 minutes.

Visibility

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 64-3. The authors of this report have shared with many colleagues throughout the world in the development of visibility as a science and as an engineering procedure. The report is intended to provide an overview of some applied aspects of this subject. Sufficient input data has been included to enable certain sample visibility calculations to be carried out by those who wish to explore this branch of optical engineering, but a full professional treatment of the subject would require a book-length treatise. In order to achieve broad coverage and yet adequate technical depth in a compact report, it has been deemed best to call upon an integrated team of specialists to produce a unified presentation with each individual contributing in his specialty. Each major section of the present report, therefore, bears the name of the specialist who prepared it.

Concealment design by engineering methods

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 61-16. In the low-visibility type of camouflage and concealment, a useful criterion of the effectiveness of the measure taken is the sighting range of the target. This range is a function of the contrasts produced by. the various surfaces of the tacget against its background. Minimization of these contrasts minimizes the sighting ranges and is, therefore, an essential first step in the design of concealment measures.An engineering method has been developed by this Laboratory for minimizing the contrast of a Navy vessel under specified conditions. The purpose of this report is to describe the method and to illustrate the effectiveness of its use.

Investigation of errors in the measurement of radiant energy for correlation with primary productivity

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 67-11. Biologists who are interested in the primary productivity of the ocean are often unable to make productivity determinations by the "in situ" technique because of the demands of other groups on the ship's time. Under these conditions it has been the practice to use a substitute technique called the "deck incubator" technique, in which the sample of plankton-bearing ocean water is transferred to a deck incubator and allowed to propagate for an appropriate length of time before determining the 14C uptake.From a radiometric point of view these two techniques differ to a considerable degree. In the "in situ" technique the plankton-bearing ocean water is returned to its original depth location where propagation takes place at normal radiant energy levels and with normal spectral and geometric distribution of the radiant energy. In the "deck incubator" technique the radiant energy level available is usually much too high and must be controlled, the spectral distribution...

Practice effects in the performance of a simple visual discrimination task by initially naive observers

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 62-21. An experiment was conducted to evaluate the effects of early-practice during training in a simple visual discrimination task. Four experimentally naive subjects completed a series of fiftyxexperimental sessions, and their data, based upon threshold estimates reduced from 50,000 observations, were examined for both short-term and long-term practice effects. Short-term effects were found to be limited to very early sessions, with essential stability of sensitivity having been reached by the fifth session. This result is consonant with other studies of training effects in the visual domain. Long term effects, up to the fiftieth session at least, were not found. It has been concluded that naive observers may confidently be assumed to have attained a stable level of performance after very few training sessions in tasks requiring a simple discrimination.

Atmospheric optical measurements in western Florida, Flight 112, Part II: Sky luminances

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 60-32. The Visibility Laboratory of the University of California, La Jolla Campus, is engaged in an on-going research program concerning optical image transmission through the atmosphere. In connection with thi3 work several data gathering flights were made in western Florida in the vicinity of Eglin Air Force Base in the spring of 1957. Flight 112, during which data in this report were measured, was one of these flights. Part I of this report, SIO Reforence 60-22, of April I960, presented data as a c atalogue of recorded optical measurements less sky luminance and sky radiance distributions. This part of the report, Part II, presents the sky luminance distribution as it varied with altitude, zenith angle, and azimuth with respect to the sun. Sky radiance distribution will be presented at a later date as Part III of this report.

Atmospheric optical measurements during high altitude balloon flight, Part IV: Sky radiances in the 580-700 millimicron region

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 61-3. Certain optical measurements of the atmosphere were made by the Visibility Laboratory of the University of California, San Diego, 21 June 1958 over central Minnesota. Data were recorded from daybreak to midmorning during the time four balloons carrying optical instrumentation from the Geophysics Research Directorate, Air Force Research Division, Bedford, Massachusetts, were floating- at higher altitudes.

Atmospheric optical measurements in western Florida, Flight 112, Part IV. Sky radiances (red)

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 60-56. The Visibility Laboratory of the University of California, La Jolla Campus, is engaged in an on-going research program studying the transmission of optical images through the atmosphere. In connection with this work several data gathering flights were made in Florida, in the vicinity of Eglin Air Force Base, in the spring of 1957. Flight 112, during which data in this report were measured, was one of these flights.

Extraction and extension of matrices in computer calculations

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 60-43. The problems involved here are: The extraction of a submatrix from a matrix; and the extension of a matrix to a matrix of larger dimensions with the original matrix as a given submatrix of the larger and the rest of the larger matrix composed of zero submatrices.

Atmospheric optical measurements during high altitude balloon flight, Part II: Sky luminances

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 61-1. Certain optical measurements of the atmosphere were made by the Visibility Laboratory of the University of California, San Diego, 21 June 1958, over central Minnesota. Data were recorded from daybreak to midmorning during the time four balloons carrying optical instrumentation from the Geophysics Research Directorate, Air Force Research Division, Bedford, Massachusetts, were floating at a higher altitude.

Atmospheric optical measurements in western Florida, Flight 112, Part III: Sky radiances (blue)

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 60-55. The Visibility Laboratory of the University of California, La Jolla Campus, is engaged in an on-going research program studying the transmission of optical images through the atmosphere. In connection with this work several data gathering flights were made in Florida, in the vicinity of Eglin Air Force Base, in the spring of 1957. Flight 112, during which data in this report were measured, was one of these flights.

A feasibility study of photo electric anti-collision systems

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 60-49. The Visibility Laboratory has for a number of years carried on a program of investigation of the possible application of visible spectrum photoelectric systems to problems of search and detection. On the basis of this experience, this laboratory was requested by the Navy to carry out a short term study of the feasibility of anti-collision instrumentation utilizing photoelectric apparatus operating in the visible spectrum. This report contains the results of this brief study program.

Visual contrast thresholds for large targets. Part II, The case of high adapting luminances

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 60-31. Systematic data relating target size to the contrast necessary for detection at various levels of adapting luminance have heretofore been limited to 6 and lower. In many practical situations, however, larger target subtenses are involved, and the solution of visibility problems by established nomographic means has been impossible owing to lack of input visual performance data for large targets. The hypothesis has been advanced that the limiting target situation might reasonably be equivalent to the instance in which the entire visual field is divided, as it becomes fatuous to speak of targets larger than can be accommodated in the binocular visual field.An experiment was performed which yielded data for both the upper limiting circular target size of the previously used data of the Tiffany research (6°) and for a "split field" in which the target comprised a luminance increment on one half of the visual field. Six levels of background luminance were studied;...

Feasibility study of a photoelectric system for detection of downed aviators

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 60-45. The function of a photoelectric system should be to improve upon the performance capabilities of unaided visual search. This report will therefore start with a very brief analysis of the visual detection capability. Succeeding sections of the report will discuss each parameter of the search geometry and indicate, where possible, modification of the parameter which will lead to improved performance. The final sections will describe a photoelectric system capable of incorporating the improvements indicated in the paragraphs which precede it and capable of day and night operation at a performance level surpassing the specified Navy requirements.

Some spectral sky radiances with different relative humidities

Thu, 20 Jun 2013 00:00:00 +0000

SIO Reference 60-29. When sky spectral radiance measurements which were made during operational tests of a spectroradiometer were compared it was seen that there was a close relationship between the value of spectral radiances and. relative humidities.

Atmospheric optical measurements in western Florida, Flight 112, Part I