摘要:

Atmospheric‐density measurements in the altitude range from 70 to 115 km were obtained from five rocket flights of the accelerometer‐instrumented inflatable sphere. We compare some of these data with data from other experimental methods to determine density. Agreement with results of pitot‐static probe and grenade experiments is within a few percent while comparison with data from the passive falling sphere technique indicates discrepancies of from 15% to 20%. The results of duplicated pairs of flights in March and May show that the atmospheric‐density variation at 105 km can be at least 70%. The experimental technique is described and the accuracy of the measurement assessed. New drag coefficients from recent ballistic range measurements are used in the calcu

ISSN:0148-0227    

DOI:10.1029/JC076i018p04145

年代:1971

数据来源: WILEY

摘要:

Sound waves in a medium with electric space charge produce oscillating electric fields by modulating the space charge. We consider the theory of this phenomenon as it applies to the atmosphere and find, for example, that sound waves at a frequency of 100 Hz from a speaker delivering 103watts/m2power at the electrodes produce a potential difference ΔΦ (in µ‐volts) between two electrodes 20 cm apart of ΔΦ(μv) ≈ 4 σ(pcoul/m3), where σ is the space charge density in 10−12coulombs per m3. The potential is inversely related to the frequency and at 20 Hz the coefficient of σ is 20. Thus, the technique is capable of detecting typically encountered atmospheric space charge. This principle has an advantage compared to other methods of high sample rates which may make it useful for monitoring from a moving station, although if sharp filtering is required in practice, the response time w

ISSN:0148-0227    

DOI:10.1029/JC076i018p04153

年代:1971

数据来源: WILEY

摘要:

An airborne laser wave‐profiler was used to estimate fetch‐limited, one‐dimensional wave number spectra by flying seaward of Cape Henlopen, Delaware, to a distance of 95 nautical miles, following passage of a cold front associated with a mean horizontal wind speed of 14 meters sec−1. The equilibrium range constant was estimated at 4.2×10−3, and it is shown that the constant may be overestimated or underestimated depending on assumed angular spreading of the waves. ‘Overshoot’ observed in these one‐dimensional wave number spectra is associated with angular spreading. Linear and exponential growth parameters estimated from fetch‐limited wave spectra are in reasonable agreement with other field investigations. Observations of exponential wave growth generally support the Miles‐Phillips predictions in the range 12≤C/U*≤21 where C is the phase speed of the wave andU*

ISSN:0148-0227    

DOI:10.1029/JC076i018p04160

年代:1971

数据来源: WILEY

摘要:

Airborne measurements of the total heat flux from the sea were successfully made during the Barbados oceanographic and meteorological experiment in May 1969. The values found at night ranged from 0.05 to 0.45 cal cm−2min−1and are half‐hour averages over contiguous strips of ocean 1.6 km long and 75 meters wide. These are the first airborne measurements of this oceanic factor and the method used i

ISSN:0148-0227    

DOI:10.1029/JC076i018p04172

年代:1971

数据来源: WILEY

摘要:

Infrared observations from spacecraft are used to investigate the response of the Somali Current to the onset of the southwest monsoon. Selected satellite observations from three years were available for this study (Nimbus series 1966, 1969, and 1970). The time‐dependent development of horizontal temperature gradients at the sea surface serves as an indicator for the formation of the baroclinic structure of the Somali Current. A comparison is made with the simultaneous development of the southwest component of the monsoon wind. The investigation reveals that the temperature gradients during the early formation stage in all years are directly proportional to the wind speed. The phase lag between the development of wind and temperature gradient during the buildup of the boundary current has a mean value of twelve days. During the decay period in late summer and fall, the lag increases continuously up to forty days. The observations suggest that two phenomena of different spatial scales play an important role during the formation of the Somali Current; in the early stage (May, June), local wind‐induced upwelling seems to be the more important source of baroclinicity; in the later stage of the buildup (July), large‐scale geostrophic effects seem to be domin

ISSN:0148-0227    

DOI:10.1029/JC076i018p04181

年代:1971

数据来源: WILEY

摘要:

If the abyssal plains have been formed by the transport of material in suspension flows, the slopes of the plains must be consistent with the dynamics of the flows. A solution of the momentum and conservation equations predicts a critical bottom slope below which the flows are not self‐sustaining in the presence of bottom friction even for particles with negligible fall speed. Two types of flow, in which either the depth or the concentration is held constant, both yield critical slopes of the order 1/1000. It appears that for slopes less than this value deposition of material must occur. The region of deposition may be shown to extend at least a few hundred kilometers. Thus suspension flow provides a suitable mechanism for the formation of surfaces with the observed range of abyssal slope

ISSN:0148-0227    

DOI:10.1029/JC076i018p04188

年代:1971

数据来源: WILEY

摘要:

Using a dynamic model we have calculated the zonal average climate forced by mean insolation conditions that prevailed 10,000 and 25,000 years ago, keeping all other physical factors constant. The results indicate minor changes in the temperature, wind, and hydrologic conditions that do not appear to be significant in accounting for variations on the scale of the late Pleistocene glaciations.

ISSN:0148-0227    

DOI:10.1029/JC076i018p04195

年代:1971

数据来源: WILEY

摘要:

Differences in the frequency content of the vertically polarized sferic signal from cloud‐to‐ground discharges and the horizontally polarized sferic signal from cloud‐to‐cloud discharges are reported. A model has been developed to consider these differences and to explain the trends in the frequency content of the measured sferics in the frequency range from 10 kHz to

ISSN:0148-0227    

DOI:10.1029/JC076i018p04198

年代:1971

数据来源: WILEY

摘要:

The newly measured solubility constant of CO2in water, α0, and in sea water and NaCl solution, α, can be easily shown by the Setchénow equation log α/α0= (0.00404 ‐ 0.000037t) × Cl‰ = (0.126 ‐ 0.00115t) ×mwhere α0= 770.5 ‐ 29.78t+ 0.6823t2‐ 0.00709 ×t3(10−4moles/liter/atm). The previous α data in water and NaCl solution by Bohr (1899) and in sea water by Krogh (1904) essentially agree with this report. Buch's (1951) estimation of a in sea water from Bohr's data

ISSN:0148-0227    

DOI:10.1029/JC076i018p04203

年代:1971

数据来源: WILEY

摘要:

A mathematical model for diffusion and advection in accumulating sediments is presented. The model's influence on material transport and concentration is discussed. It is concluded that previous authors were justified in using simpler models by neglecting the advective terms, but cases could arise in which these terms would be of importance.

ISSN:0148-0227    

DOI:10.1029/JC076i018p04208

年代:1971

数据来源: WILEY