摘要:

On the basis of the gravity material available, the author studies two statistical functions:G2= the rms (root mean square) anomaly in a square with sides, andE2= the rms deviation of one actual point anomaly from the actual mean anomaly in a square with sides.The functionE2, is called the error of representation, for if inside a square there is only one observed anomaly and this anomaly is accepted to represent the mean anomaly of the entire square, a standard mean errorEcan be used for the estimation of accuracy. On the other hand, if there are no observations inside the square and the mean anomaly of the square is assumed to be zero,Gcan be used as the standard mean error.For points or for very small squares,Eis zero andGhas a maximum valueG0. For a hemisphere,Gis zero andEhas a maximum valueG0. There is a critical size at abouts= 3°, whereE=G. Whensis greater, it is not advisable to use the observed anomaly at a single station, as the representative of the mean anomaly of the square, because for zero the error to be expected is smaller. The weighted mean of zero and the observed anomaly is recommended.Because the regions without any observations are still large, it is necessary to estimate the size of the smallest squares, where the mean anomaly can be assumed to be independent of the mean anomalies of the adjacent squares. On the basis of the present gravity data, an estimated value ofs= 30° seems to be acceptable.Using the functions E and G and the accepted valuess= 3° ands= 30°, the precision obtainable for the gravimetric determination of the elevationsNof the geoid (Stokes' formula) and of the deflections δ of the vertical (Vening Meinesz' formula) has been estimated. In the most favorable cases (Central Europe and the central parts of the United States) the standard mean error ofNis ±10 meters and that of δ ± 0.″85. The former figure is almost entirely due to the great unexplored areas of the Earth'; the latter depends half on these unexplored areas and half on the small gaps within a distance of 50° from the point where δ

ISSN:0002-8606    

DOI:10.1029/TR037i001p00001

年代:1956

数据来源: WILEY

摘要:

In the extrapolation of geomagnetic components, a theoretical treatment of the Taylor series shows that the ratio of the absolute value of successive terms of the series approaches the limith/awherehis the extrapolation distance andais the radius of the Earth. Expressions are presented for the limiting form of the remainder after a certain finite number of terms of the series. These expressions, which comprise the product of a computed term and a binomial series, may be used to limit the number of partial derivatives that need to be computed

ISSN:0002-8606    

DOI:10.1029/TR037i001p00009

年代:1956

数据来源: WILEY

摘要:

This paper reports a study of the correlation coefficients between eddy velocity components measured at two different points in space, the energy spectrum, and the rate of dissipation of energy in a low‐speed turbulent jet. The result of this study shows that the local isotropy proposed by Kolmogoroff prevails. It also gives the order of magnitude of the mean rate of dissipation of energ

ISSN:0002-8606    

DOI:10.1029/TR037i001p00013

年代:1956

数据来源: WILEY

摘要:

A compact self‐contained long‐period wave recorder has been developed for remote operation on small islands where the influence of continental land masses is minimized. The instrument can be installed in two or three days, requires no electric power, and needs only weekly attention. It can detect waves less than one cm high at its period of maximum response (1000 sec), and it attenuates both swell and tides to about three per cent of their relative amplitu

ISSN:0002-8606    

DOI:10.1029/TR037i001p00027

年代:1956

数据来源: WILEY

摘要:

Various methods for potentiometric determination of the endpoint of a titration are discussed and sources of error considered. In the routine determination of salinities for dynamic‐height computation using a commercial Ag indicating electrode and Ag‐AgCl reference electrode, the equivalence point potential should first be determined with an accuracy of ten mv and the meter set to this value. The procedure of Knudsen is then followed and all samples and standards titrated to within five mv of the established endpoint potent

ISSN:0002-8606    

DOI:10.1029/TR037i001p00031

年代:1956

数据来源: WILEY

摘要:

Upwelling in the Gulf of Mexico and along the coast of California has been treated theoretically by Hidaka for steady‐state conditions. An extension of this work is presented which considers the transient state in which upwelling and coastal currents gradually develop in an ocean initially at rest when the wind suddenly begins to blow over the sea surface. Expressions for the component velocity in thexandydirections, for the vertical component, and for the vortieity in the direction of the z axis are derived. A numerical example is included using the expression derived for thexcomponent of the curre

ISSN:0002-8606    

DOI:10.1029/TR037i001p00038

年代:1956

数据来源: WILEY

摘要:

Evaporation is a physical process that must satisfy two basic requirements. There must be an energy supply to provide heat of vaporization; and there must be some transport mechanism for removing the vapor. Combining these concepts it is possible to derive an expression for evaporation rate that depends only on measureable weather elements. By making some simplifying approximations, the weather data needed reduce to (a) duration of bright sunshine, (b) air temperature, (c) air humidity, and (d) wind speed. The quantity obtained isEO, the evaporation rate for a hypothetical open water surface exposed to the measured weather. Formally, and empirically, it is possible to convertEOintoET, the potential transpiration rate from a short green crop cover, completely shading the ground and never short of water. This computation has formed the basis of successful experiments in irrigation control; and, with reasonable empirical modification to allow for conditions when water supply becomes a limiting factor, has been applied with some success in studies of the water balance of catechment areas. Applied to two classical American watershed studies it suggests that some of the Coweeta results may need reconsideration.

ISSN:0002-8606    

DOI:10.1029/TR037i001p00043

年代:1956

数据来源: WILEY

摘要:

The period of vibration and the surface shape for the fundamental and several harmonics for free longitudinal oscillations have been deduced for Lake Wakatipu, New Zealand, from the behavior of a laboratory model similar to the Lake. The chief advantages of the model analysis as opposed to full algebraic treatment are the superior speed and the possibility of assessing the accuracy of the results by minor alterations in the original model.

ISSN:0002-8606    

DOI:10.1029/TR037i001p00051

年代:1956

数据来源: WILEY

摘要:

Numerous investigations of suspended‐sediment discharge have shown that an increase in stream flow usually is accompanied by an increase in sediment concentration. The sediment‐concentration peak during a rise may precede, coincide with, or follow the water‐discharge peak. Observations on the Bighorn River in Wyoming and Montana show a progressive lag in peak concentration behind peak flow. The lag is most apparent when a single storm produces a flood wave that starts many miles upstream from the sampling sec

ISSN:0002-8606    

DOI:10.1029/TR037i001p00056

年代:1956

数据来源: WILEY

摘要:

To increase the value of range land densely covered by brush, a number of management practices are being employed. One practice, clearing by the use of fire, has raised the question as to its effect on the infiltration capacity of the soil. Application of single‐ring infiltrometers for determining relative infiltration rates of upland soils is discussed. Values of the relative infiltration rates for burned and unburned areas are presented. In all cases the burned soils had substantially higher rates following a fire. One year later the results were similar with one exceptio

ISSN:0002-8606    

DOI:10.1029/TR037i001p00067

年代:1956

数据来源: WILEY