摘要:

Mr. President, members and guests of the American Geophysical Union: I have known Richard Montgomery Field since 1926—first as student, then as an assistant, and finally as a colleague. There is much I owe to him, and I am happy to be the one asked to present him to you this evening as the Sixteenth Recipient of the Bowie Medal.Looking back at previous medalists, Gutenberg, Jeffreys, Sverdrup, Adams, Lambert, Macelwane, Meinesz, Daly, Bjerknes, Bigelow, Meinzer, Heck, Fleming, Day, and Bowie, I think it is fitting that Field's name should be the next on this list of truly great men in the development of geophysics in this country. He was President of the Union 15 years ago and perhaps did more to advance it as a vigorous scientific society than any man except John Flemin

ISSN:0002-8606    

DOI:10.1029/TR035i003p00389

年代:1954

数据来源: WILEY

摘要:

A method is developed whereby latitude, longitude, and azimuth are deduced simultaneously from azimuth observations on three or more stars. The method is particularly advantageous for high latitudes. A set of observation equations of the form x (dΦ) + y (dλ) − (dA) + ℓ = 0 are solved by least squares for the best values of (dΦ), (dλ), and (dA), the corrections to assumed values of the latitude, longitude, and azimuth. Criteria for sharpness of determination are given. The discussion includes the choice and identification of stars and the computation of a numerical example. Using the most favorable selection of stars, and eliminating personal equation, geographical positions correct, astronomically, to about one‐half a second of arc may be obtained by th

ISSN:0002-8606    

DOI:10.1029/TR035i003p00391

年代:1954

数据来源: WILEY

摘要:

The paper outlines procedures used in the examination of data received from 21 field stations. Figures are provided to illustrate the type of records examined and the results of interstation comparison. Stations separated by not more than four degrees of geomagnetic latitude are compared graphically as regards monthly medians of the various characteristics. Discoveries of operating errors which had escaped observation for several months are described. A type of scaling error discovered by graphical comparison of stations is mentioned.

ISSN:0002-8606    

DOI:10.1029/TR035i003p00398

年代:1954

数据来源: WILEY

摘要:

Regression formulas are developed from which estimates of the monthly normal precipitation at a station having a short record can be obtained. Using stations in western Washington the method is illustrated for records of ten years, five years, and one year in length. The error decreases as the length of record increases and the amount of error can be estimated. The computation of a single regression of 32‐year means on ten‐year means involving 30 stations permits the estimation of normals for all stations in western Washington having only ten years of rec

ISSN:0002-8606    

DOI:10.1029/TR035i003p00405

年代:1954

数据来源: WILEY

摘要:

Each of 34 Friez microbarograph records of pressure variations associated with showers or thundershowers in the past five years near St. Louis has individuality, yet they indicate that there is an idealized thunderstorm microbarogram, which can be subdivided into five pressure stages. Each record exhibits at least one of the stages. Causes of the pressure changes are discussed.

ISSN:0002-8606    

DOI:10.1029/TR035i003p00413

年代:1954

数据来源: WILEY

摘要:

An analysis is made of oceanographic observations taken aboard tankers over a period of one year between Key West and Cape Hatteras. The Gulf Stream is shown to have seasonal and tidal fluctuations in speed and position. Meanders, known to exist to the north, are shown to exist as far south as the Straits of Florida.

ISSN:0002-8606    

DOI:10.1029/TR035i003p00420

年代:1954

数据来源: WILEY

摘要:

A theory of upwelling and coastal currents induced by longshore and offshore winds is derived, taking the effects of Coriolis forces and horizontal and vertical mixing into account. In the first place, it is shown that an upwelling circulation can be caused in the vertical plane perpendicular to the coast by a wind blowing parallel to the coast in such a manner that, in the northern (southern) hemisphere, the coast is on the left‐hand (right‐hand) side of an observer with his back to the wind. The result agrees with the facts observed in the regions off the Southern Californian and Peruvian coasts very satisfactorily. The velocity of upwelling is computed at about 80 m/month, a value consistent with that estimated from observed hydrographic data. Next, it is shown that an offshore wind blowing perpendicular to the coast can also give rise to a similar circulation in the same vertical plane, but in this case with much weaker intensity. From these results it can be concluded that the most intense upwelling will occur when the wind makes an angle of 21°.5 with coast line in an offshore direction. In addition to these circulations in the vertical plane, there exist horizontal currents parallel to the coast. These will contribute to the formation of the coastal or longshore currents much debated recently. The horizontal components of the motion under consideration show a vertical variation very similar to the Ekman spiral at some distance from the c

ISSN:0002-8606    

DOI:10.1029/TR035i003p00431

年代:1954

数据来源: WILEY

摘要:

Examples from the Danish coasts demonstrate the applicability of small scale laboratory experiments with equilibrium beach profiles to interpreting observed conditions on beaches and predicting performance of coastal protection structures.

ISSN:0002-8606    

DOI:10.1029/TR035i003p00445

年代:1954

数据来源: WILEY

摘要:

During a study in which information was gathered to improve the design of unlined canals in coarse granular materials, an opportunity was afforded to study the effect of particle shape on the movement of coarse sediments. This paper summarizes the various measurements and analyses that were made on samples of bed material from several canal sections in the San Luis Valley in Southern Colorado. Some comparisons are made to show the resistance to movement of various shaped particles according to sphericity and Zingg type. It is pointed out that flat particles tend to become imbricated, and they resist movement more than spherical particles of equal weight. Some observations are made on the effect of dilatancy on scour and sediment movement.

ISSN:0002-8606    

DOI:10.1029/TR035i003p00453

年代:1954

数据来源: WILEY

摘要:

Unsaturated steady flow of mixtures of a liquid and a gas through sands and similar porous media at low Reynolds numbers obeys Darcy's law. The relative liquid permeability K is not constant, but a universal function of the degree of liquid saturation. An approximate theory gives its form, which is a cubic parabola. A similar expression is found for the gas permeability. Numerous experiments by Wyckoff ami Botset confirm the theory. This is in agreement with Gardner's hypothesis that K is a function of the concentration in water, and indirectly with Richards' hypothesis that it is a function of the capillary potential. The degree of liquid saturation seems to be a more useful unit of liquid percentage than any other.

ISSN:0002-8606    

DOI:10.1029/TR035i003p00463

年代:1954

数据来源: WILEY