bluuebunny/crossref_metadata_2025_split huggingface dataset:
Short‐period variations in the atmospheric electric potential gradient
Authors: Whitlock W. S. , Chalmers J. Alan 
Published: February 2007

AbstractMeasurements made with 2 field mills, 100 m apart, along the direction of the surface wind, have been used to obtain information about the charges responsible for variations in the potential gradient over periods of the order of minutes. In general these variations are caused by the horizontal motion of wind‐home space charge contained within the first few hundred metres of atmosphere. In fair weather, there are effects probably caused by locomotive steam, and others perhaps to be associated with convection cells. In overcast weather there is evidence for concentrations of negative charge in the base of the thicker portions of the cloud. In showers, the main result is that the pattern of the potential gradient is very much affected by space charges from point discharge.
On the heat balance and maintenance of circulation in the trades
Authors: Riehl H. , Malkus Joanne S. 
Published: February 2007

AbstractThe heat balance is calculated for the Pacific north‐east trade during summer and it is shown that the trade exports sensible as well as latent heat. The sensible‐heat gain is related to the surface pressure distribution; it is found that the low‐level circulation in the region considered is self‐driving.
A theoretical estimate of the collection efficiencies of small droplets
Authors: Pearcey T. , Hill G. W. 
Published: February 2007

AbstractThe effective collision cross‐sections between pairs of small water droplets, falling freely through air under the influence of gravity, have been computed on the assumption of hydrodynamical effects alone being important. It has been assumed that each droplet tends to fall freely at its terminal velocity with respect to the surrounding medium, which also moves under the influence of the motion of a neighbouring droplet. By the use of previously computed fields of flow of a viscous medium around a uniformly translated sphere, the trajectories of motion of one droplet with respect to another were computed for a range of droplets having radii between 4 μ and 200 μ.It is found that the collision cross‐sections increase to values considerably greater than the corresponding geometrical cross‐section as the droplets approach equality of size. As the difference in size increases, the collision cross‐section decreases to values close to the geometrical cross‐section, and finally decreases to zero. For any one particular size of the collecting droplet there is a minimum size of collected droplet below which no collection is possible. This size decreases with increasing size of the larger droplet greater than 10 μ in radius. For droplets smaller than 10 μ in radius, collision can occur only between droplets of nearly equal size. The results could account for coalescence becoming an important factor in the rapid formation of raindrops for droplets of radii greater than 10 μ.
The relation between an umkehr curve and the vertical distribution of atmospheric ozone
Authors: Walton G. F. 
Published: February 2007

AbstractAn expression is derived for the intensity‐ratio for two wavelengths in the ultra‐violet of primary scattered sunlight received from the zenith at the base of a plane‐stratified atmosphere. The logarithm of the intensity‐ratio is expanded in a series which reveals the nature of the relation between it and the vertical distribution of atmospheric ozone. The information on the vertical distribution given by zenith observations when the sun is high in the sky is discussed.
Instruments for micro‐meteorology
Authors: Long I. F. 
Published: February 2007

AbstractSeveral instruments suitable for long‐term recording of temperature, humidity and wind gradients among growing crops have been constructed. Practical details are given of the use of thermistors and miniature nickel resistance thermometers as wet‐ and dry‐bulb psychrometers, and of the use of these units for direct recording of both dew point and dew‐point gradient. Modifications of the sensitive cup anemometer, appropriate circuits and details of a ‘hot‐bulb’ anemometer using a resistance thermometer, are described.
Harmonic analysis of the mean northern‐hemisphere wind field for the year 1950
Authors: Saltzman Barry , Peixoto Josép. 
Published: February 2007

AbstractHarmonic analyses of the mean northern‐hemisphere wind field for the year 1950 along latitudes 30°, 45° and 60° are presented. The seasonal variations of these spectra are investigated and the relative contributions of the various scales of mean eddies to the meridional transport of angular momentum are calculated.
Variation with height of rainfall below the melting level
Authors: Harper W. G. 
Published: February 2007

Abstract3‐cm radar signal intensity measurements, made at a range of heights up to 6,000 ft on three days with widespread moderate rain, suggest that there was considerable uniformity of drop‐size distribution and of rainfall rate with height once melting of snowflakes was complete and terminal velocity was achieved, and that in these warm‐front type situations no significant growth of precipitation was taking place below the melting layer.
The measurement of gustiness in the first few thousand feet of the atmosphere
Authors: Jones J. I. P. , Butler H. E. 
Published: February 2007

AbstractA description is given of instruments which have been designed and used to measure gustiness, in the form of inclination and total speed of the wind, from a position on the cable of a captive balloon. A lightweight wind vane with automatic compensation for tethering cable angle, and a sensitive vane airmeter are used as sensing heads. The data, with reference signals, are relayed by electric cable to ground level and recorded on multi‐channel recorders. Both instruments have good response to wind fluctuations with periods down to one second.A brief account is given of some observations made at Cardington, Beds., and some examples are presented of records made at 1,000, 2,000 and 3,000 ft in contrasting meteorological conditions.
A numerical study of the wavelength and amplitude of lee waves
Authors: Wallington C. E. , Portnall Janet 
Published: February 2007

AbstractWavelengths and variation of wave amplitude with height are computed for 19 airstreams in which lee waves have been observed. Comparison between the computed and observed wavelengths suggests that the tropospheric flow is sufficiently independent of conditions in the stratosphere to allow reasonable latitude in making a boundary assumption at some high level.
Vanishing potential temperature gradients in strong convection
Authors: Webb E. K. 
Published: February 2007

AbstractTemperature profiles recorded up to 30 m show an unexpected feature in conditions of free convection with light wind. Above the strong lapse near the ground, there is a transition to zero potential temperature gradient. The height of the transition level falls as the wind strength decreases, becoming less than 8 m when the negative Richardson number at 1·5 m is greater than 0·4. From reported observations over the sea it seems that the feature is present there also.
The movement of precipitation belts as observed by radar
Authors: Harper W. G. , Beimers J. G. D. 
Published: February 2007

AbstractThe movement of 51 belts of precipitation of cold‐front type over south‐east England has been measured from radar records and compared with upper winds at each 50‐mb level from 950 to 500 mb. The mean speed of the belts is found to be in close agreement with the mean wind component across the belts at the 700‐mb level, with a correlation in excess of 0·9. Even at 650 and 750 mb the correlation is significantly lower, while at 950 mb it is only 0·6. The same pattern of correlations and of wind components was found in 31 belts associated with occlusion situations, and no significant variation in correlation level was found despite subdivision of the material on the basis of the height ranges of the observed echoes.A simple forecasting rule is suggested, that ‘belts of precipitation of cold‐front type move with a speed equal to the component of the 700‐mb wind across them’.
On the characterization of tropical rainstorms in relation to runoff and percolation
Authors: Hutchinson Sir Joseph , Manning H. L. , Farbrother H. G. 
Published: February 2007

AbstractThe statistical characterization of tropical rainstorms is considered. Linear relationships are demonstrated between log duration and rate, and between log amount and rate.The fate of rainfall when it reaches the ground is then considered, and it is shown that from the linear regression of amount of rain and rate, together with runoff data, percolation rates can be estimated. The consistency of estimates of percolation rate is demonstrated from data from Namulonge, Uganda, and from the Ozark Highlands in Arkansas.
A numerical study of the topographical factor in lee‐wave amplitudes
Authors: Wallington C. E. 
Published: February 2007

AbstractA numerical study of the effect of mountain shape on two‐dimensional lee‐wave flow shows that asymmetrical ridges are slightly more favourable than symmetrical profiles for the formation of lee waves, especially for short wavelengths. A technique is suggested for determining the lee wavelength when only part of the lee‐wave flow is observable.
Temperature variations at Resolute, Northwest Territories
Authors: Longley Richmond W. 
Published: February 2007

AbstractFrom a study of temperature data at Resolute, Northwest Territories, it is shown that in the Arctic regions the time of minimum temperature occurs near the end of February or in early March. This delay, relative to the corresponding time in temperate latitudes, is a result of the lack of incoming radiation during the polar night. Because of fog off open water in late July, the maximum temperature occurs during the second week of July.
World temperatures during the Pleistocene
Authors: Simpson George C. 
Published: February 2007

AbstractIn previous papers it has been shown that the glacial and pluvial periods of the Pleistocene can be explained qualitatively on the assumption that during this period there were three oscillations of solar radiation. Accepting this assumption the present day zonal temperatures ‐ mean temperatures along a circle of latitude ‐ are considered and the physics of the relationship between changes in solar radiation and the consequent changes in the zonal temperatures are discussed. By a graphical method of trial and error a family of curves relating the zonal temperatures of all latitudes with the oscillations of the solar radiation is prepared and discussed. These results are tabulated and used to plot curves showing the variations of the zonal temperatures of five latitudes between the Equator and the North Pole during a complete cycle of solar radiation and applied to the glacial and interglacial periods.The difference between the actual temperatures of any place and the zonal temperature of the latitude on which it is situated ‐ the so‐called temperature anomaly ‐ is then discussed and two diagrams are prepared showing the local temperatures at places in the British Isles and North America during the last cycle of solar radiation embracing the period from the beginning of the Mindel‐Riss interglacial to the present day. The geological evidence for the temperatures thus derived is briefly discussed.
Deposition of iodine‐131 in Northern England in October 1957
Authors: Chamberlain A. C. 
Published: February 2007

AbstractIodine‐131 and other radio‐elements were emitted from the stack of the Pile No. 1 at Windscale, Cumberland, during the night of 10‐11 October 1957. The detailed distribution of the activity deposited on the ground was determined as far south as Preston and Leeds. The deposition of the radio‐iodine is attributed mainly to diffusion to the grass, but washout by rain and precipitation from some nearby cooling towers may have increased the rate of fallout in some areas.
Estimation of surface stress and heat flux from profile data
Authors: Priestley C. H. B. 
Published: February 2007

AbstractThe problem of estimating shearing stress from the wind profile in the lowest layers is discussed from the operational viewpoint. It is concluded that wind‐profile data alone may never in practice be sufficient, even though a universal profile with the stress as a separable parameter may be established by future research. On the other hand the determination of both stress and heat flux, with adequate accuracy, may be possible from single values of temperature gradient and wind gradient observed simultaneously. A difficulty common to all indirect methods lies in interpreting the sampling variations.
Monthly charts of evaporation from the N. Indian Ocean (including the Red Sea and the Persian Gulf)
Authors: Privett D. W. 
Published: February 2007

AbstractMonthly values of the rate of evaporation from each 5‐degree square of the N. Indian Ocean and from the Red Sea and the Persian Gulf have been obtained by using a modified form of Jacobs's formula and climatic data supplied by the Meteorological Office.
Similarity theory in the relation between fluxes and gradients in the lower atmosphere
Authors: Taylor R. J. 
Published: February 2007

AbstractAvailable data on wind and temperature profiles and heat and momentum fluxes in the lower atmosphere have been examined in the light of the similarity theory of Monin and Obukhov (1954) and, except in conditions of very strong lapse where some doubt remains, reasonable agreement is found.The ‘log + linear’ profile form is investigated and it is shown that, in lapse conditions, it is applicable only to a very limited range of stability corresponding approximately with forced convection conditions. The constant, α, which enters into this profile is about 6 and thus considerably larger than the value proposed by Monin and Obukhov. The discrepancy is due to these authors' having applied the profile to a larger range of stability than is justified.Subject to the reservation expressed for the case of very strong lapse conditions, the similarity scheme has been shown to extend to free convection conditions where a – ⅓ power form of profile is more appropriate. The relevant constants are estimated.
The summer circulation of the arctic stratosphere below 30 km
Authors: Hare F. Kenneth 
Published: February 2007

AbstractThe summer circulation of the arctic stratosphere is examined in the light of climatological data and daily synoptic analysis. The Ferrel westerlies are shown to extend to about 20 km (50 mb) immediately above the jet axis. The middle stratospheric easterlies above them descend to 15 km at the pole in midsummer. The easterlies flow round the flanks of a flat‐centred anticyclone near the pole, and are almost devoid of perturbations. The lower stratosphere (tropopause to 20 km) has a disturbed thermal regime due to vertical motion associated with waves in the Ferrel westerlies or with cold lows within the westerly ring.
The carbon‐dioxide flux over a field of sugar beet
Authors: Monteith J. L. , Szeicz G. 
Published: February 2007

AbstractThe difference of CO2 concentration at two heights above a sugar beet crop was measured with a sensitive infra‐red gas analyser. The ratio of evaporation to humidity gradient and of total heat flux to wet‐bulb temperature gradient gave a transport number for calculating CO2 flux, assumed proportional to CO2 gradient and wind speed. In August and September 1958 there was often a constant upward flux at night (mean 0·05 mg cm−2 hr−1) attributed to respiration by plants and soil micro‐organisms; but during daylight, photosynthesis gave a downward flux varying with solar radiation and reaching a maximum of 0·4 mg cm−2 hr−1. From 31 July to 11 September the net downward flux of atmospheric CO2 was 158 ± 29 mg cm−2 compared with an uptake of 217 ± 38 mg cm−2 estimated from dry matter increase of sampled plants. During October there was a net upward flux of 4·9 mg cm−2 day−1 attributed to a striking increase in amount of CO2 produced in the soil.
The accuracy of determination of the vertical distribution of atmospheric ozone from emission spectrophotometry in the 1,043 cm−1 band at high resolution
Authors: Walshaw C. D. 
Published: February 2007

AbstractA method is outlined for obtaining the vertical distribution of atmospheric ozone from ground‐level measurements of the downcoming thermal radiation in the region of the 1,043 cm−1 (9·6 μ) band. The emission measurements are such as may be made with a grating spectrometer of the Goody type; the slit width is about 2·5 cm−1, enabling interference from water vapour and carbon‐dioxide lines to be eliminated.Estimates are made of the various sources of error, using a model atmosphere having three ozone variables (which are the ozone contents of the layers 1,000–600, 600–300 and 300–50 mb), and basing the analysis on four combinations of wave number and zenith angle of observation.It is concluded that results of useful accuracy may be obtained for the two tropospheric layers, but that the method is not sufficiently sensitive to give significant information on the upper layer. The continuous absorption over the region lowers the accuracy appreciably but does not affect the main conclusion.
The variation in composition of sea‐salt nuclei with mode of formation
Authors: Oddie B. C. V. 
Published: February 2007

AbstractIt is shown that at coastal stations, while the coarser spray has a composition close to that of sea water, the smaller droplets (diameters less than about 25 microns) have a much higher proportion of potassium. The rapid decrease in the Na: K ratio with increasing distance from the sea is principally due to the settling out of the coarser spray. The result is consistent with Wilson's hypothesis that salt nuclei are formed largely from an extremely thin surface layer very rich in organic matter, which contains a high proportion of potassium.
Some notes on the stratospheric winds at Canton Island and Christmas Island
Authors: Ebdon R. A. 
Published: February 2007

AbstractStratospheric wind data for Canton and Christmas Islands show a fluctuation with a period of about 24 to 28 months in the zonal component. Christmas Island data also show that the fluctuation exists from below 60 mb to 10 mb (the highest level for which data are available) and that the amplitude of the fluctuation increases with height. The change in wind direction from W to E, or vice versa, is evident first at the higher levels and appears to work gradually downwards; at 60 mb the reversal of wind direction is evident about six months after that at 25 mb, and about twelve months after that at 10 mb.Attempts to connect events in the equatorial stratosphere with events in the equatorial troposphere were not successful.
Project Jet Stream Research Flight No. 30, April 1957
Authors: Reiter E. R. 
Published: February 2007

AbstractAn analysis is made of Project Jet Stream Research Flight No. 30, conducted on 8 April 1957. This flight made several traverses through a pronounced jet stream over the New England States. The fields of wind speed, potential temperature, vorticity and divergence are presented in vertical cross‐sections. Special reference is made to the differences between geostrophic and actual vertical wind shear in the vicinity of the jet core.
Measurements of evaporation and heat transfer in the lower atmosphere by an automatic eddy‐correlation technique
Authors: Dyer A. J. 
Published: February 2007

AbstractFollowing the development of an automatic instrument for the determination of evaporation and sensible‐heat transfer by the eddy‐correlation technique, a large number of measurements of these eddy fluxes have been made over level pasture‐land. The observations, taken at a height of 4 m, are in excellent agreement with the energy balance. Individual measurements, of 5‐min duration, are distributed about a strict energy balance with a standard deviation of 31 per cent, due mainly to horizontal gradients of wind, temperature, and humidity below 4 m height. Over a period of several hours these gradients average out to negligible values.The short response time of the sensing equipment (∽ 0·3 sec) ensures that, for conditions of moderate and high instability, significant deficiencies in eddy‐flux measurements occur only with winds exceeding 10 m sec−1.A quantity ϵ, the ‘evaporation fraction,’ i.e., the ratio of evaporation to evaporation plus sensible‐heat transfer, is found to increase markedly after rain, and to gradually decrease during the succeeding dry period. This increase can be quantitatively related to the amount of rain. The average value of ϵ during February‐March 1960 was 0·56, whilst a value of 0·54 can be computed from annual totals of precipitation and net day‐time radiation income.
Design of interference filters for the observation of infra‐red emission from atmospheric carbon dioxide by an earth satellite
Authors: Smith S. D. 
Published: February 2007

AbstractDetailed proposals are made for the design of a high‐order Fabry‐Perot type interference filter in which the transmission bands of the filter are exactly matched to 15 lines of the R‐branch of the CO2 spectrum near 15 μ. The striking energy advantages of such an interferometer are discussed and it is shown that use of an optically worked high‐index germanium spacer leads to a further considerable increase in light grasp. It is concluded that technical problems are not severe and a calculation of the energy that can be collected by the proposed system suggests that a detector of area 9 mm2 with a noise‐equivalent‐power of 10−10 watts (i.e. comparable with a standard Golay cell) can provide adequate sensitivity.
Atmospheric observations of line intensity and half‐width in the rotation and ν2 vibration‐rotation bands of water vapour
Authors: Saiedy F. 
Published: February 2007

AbstractCurves of growth have been measured in the solar spectrum between 8 and 13 μ on five atmospheric water‐vapour lines, three in the rotation band and two in the ν2 vibration‐rotation band. The water vapour in the path, from radiosonde data, was never less than 1 g cm–2, so that it was possible to measure S0 (the line intensity at T0 = 273°K) and α0 (the half‐width at p0 = 1,000 mb) separately only for the weak line at 914.03 cm–1, with errors of approximately 3 and 5 per cent respectively. For four strong lines at 871.32, 878.61, 1106.74 and 1111.53 cm–1 only the product S0 α0 could be obtained, with an estimated error of 8 per cent. The results of the rotation lines show reasonable agreement with theoretical values. Using theoretical values of α0, the normalizing factor n̈ for the two n̈2 lines are 0·0165 for 1106·74 and 0·0126 for 1111·53 cm–1, which differ considerably from the overall normalizing factor 0·005 given for this band by Benedict et al. (1952) and show a slight dependence on the rotational quantum number J.
Vertical series of sea and air temperatures close to the surface, taken aboard the yacht Petula in the tropical Atlantic
Authors: Evans F. , Dickson C. N. , Kove N. A. G. 
Published: February 2007

AbstractSea and air temperatures were taken at a number of points within 2 m of the surface. In general, both sea and air temperature profiles were almost isothermal at more than 1 m from the surface. Air temperatures gave some indication of a change from neutral to stable conditions above about 55 cm. There was little confirmation of an earlier suggested similarity between profiles of wind, temperature and humidity under near‐neutral conditions.
Point discharge from natural and artificial points (Pt. II)
Authors: Milner J. W. , Chalmers J. Alan 
Published: February 2007

AbstractMeasurements have been made of the point‐discharge current through an artificial point at about tree‐top height, the potential gradient at the ground nearby and the wind speed. The results are similar in form to those for an isolated point at greater height and do not show the square‐law relation between current and potential gradient that has previously been found when wind‐speed has not been taken into account. The current flowing down a living tree has also been measured and obeys a similar relation with potential gradient.