bluuebunny/crossref_metadata_2025_split huggingface dataset:
Further data concerning the distribution of water vapour in the stratosphere
Authors: Murcray D. G. , Murcray F. H. , Williams W. J. 
Published: February 2007

AbstractThe variation of the infra‐red solar spectrum with altitude was observed during a balloon flight made on 24 March 1964, from Alamogordo, New Mexico. A water vapour mixing ratio profile determined on the basis of the variation with altitude of the infra‐red solar spectrum in the vicinity of 3,854 cm−1 during this flight is presented. This profile is in agreement with the view that the mixing ratio in the vicinity of the tropopause is about 2.10−6 g g−1; however, it also indicates that the mixing ratio increases again above 65,000 ft.
The budget of turbulent energy near the ground
Authors: Hess G. Dale , Panofsky H. A. 
Published: February 2007

AbstractOn the basis of wind records on two days at the Brookhaven tower at Upton, New York, it is tentatively concluded that, in equilibrium, mechanical energy production and energy dissipation are not significantly different from each other, even if the stratification is quite unstable. Change from rough to smoother terrain, however, produces a state of non‐equilibrium in which dissipation may greatly exceed production.
The effect of contamination on spectroscopic determinations of stratospheric water vapour
Authors: Houghton J. T. 
Published: February 2007

AbstractThe effect is considered of the presence of water vapour in the optical path of a spectrometer used to measure absorption by atmospheric water vapour. If such possible contamination is ignored, the water vapour mixing‐ratio profiles deduced from the measurements will show increasing mixing‐ratio with altitude in the stratosphere.
An approximate treatment of the effect of thermal stability on turbulent diffusion
Authors: Gee J. H. 
Published: February 2007

AbstractAssuming a wind profile of form u oc zm where m is a function of the stability parameter L, the effect of stability on turbulent diffusion is investigated. Swinbank's exponential wind profile yields the relation m = 0.1340 + 0.244 L−1 + 0.22 L−2 and a drag coefficient implied by \documentclass{article}\pagestyle{empty}\begin{document}$ \[ \frac{{u_1 }} {{u_* }} = \frac{1} {k}In\left[ {\frac{L} {{z_0 }}\left( {\exp \left\{ {{2 \mathord{\left/ {\vphantom {2 L}} \right. \kern-\nulldelimiterspace} L}} \right\} - 1} \right)} \right] \] $\end{document}.On this basis, curves showing the dependence of point‐concentrations on stability are drawn for eddy diffusion and evaporation problems. These indicate, among other things, the existence of a lower region where concentration increases with stability and an upper region where concentration decreases with stability; they also show that the total rate of evaporation from a liquid surface decreases by about five per cent as L−1 increases from −0.2 m−1 to + 0.2 m−1.
A preliminary map of summer albedo over England and Wales
Authors: Barry R. G. , Chambers Ruth E. 
Published: February 2007

AbstractAlbedo data are presented from ground and airborne measurements over different types of cover in Southern England. Summer values show a range of at least 10 per cent (15 per cent for heath, 16 to 18 for woodland and built‐up areas and 24 to 25 per cent for green cereals and grass). These and published albedos are used to prepare a map of summer albedo over the country based on the vegetation maps in The Atlas of Britain.
A note on the effect of directional wind shear on medium‐scale atmospheric diffusion
Authors: Gee J. H. 
Published: February 2007

AbstractDiffusion of matter from an instantaneous point source in a directional wind shear is treated theoretically using the eddy diffusion equation, and the results are compared with medium‐scale diffusion experiments by Pasquill (1962) and with deductions based on a statistical theory by Högstrom (1964). The effect of ‘shearing advection’ on the theoretical solution is also considered and (contrary to previous results by Gee and Davies (1963, 1964) concerning diffusion near the surface) this is shown to be small, if the theory is based on the assumptions that the vertical eddy diffusivity and the vertical mixing length are constants.
Laplace's tidal equations – an application of solutions for negative depth
Authors: Corby G. A. 
Published: February 2007

AbstractIt is shown that solutions of Laplace's tidal equations in the presence of a non‐zero zonal flow may be obtained from the usual solutions for perturbations about a state of rest relative to the Earth, provided one uses an appropriate modification of the equivalent depth. Typically the modification leads one to the solutions which for zero zonal flow would be applicable to negative depths.
The surface configuration and internal structure of artificial hailstones
Authors: Bailey I. H. , Macklin W. C. 
Published: February 2007

AbstractAn experimental study has been made of the external and internal structure of artificial hailstones grown freely supported in a vertical wind tunnel. In addition the nature of ice deposits formed on fixed stationary objects and objects rotating about a horizontal axis has been investigated at airspeeds of 35 to 40 m s−1. Lobe‐like growth similar to that found in natural hailstones has been reproduced. The lobes are most pronounced when the accreted droplets are small and when growth takes place near the wet limit. With large droplets and when the growth is very spongy the surface irregularities are far less marked. It is inferred that the lobe‐like growth is due to a collection efficiency effect.The drag coefficients of a number of artificial hailstones have been measured. None of the values is greater than 0·66. Some of the moderate sized stones (4 to 6 cm diameter) entered the critical flow regime where their drag coefficients were considerably reduced. This did not occur, however, for large (10 cm diameter) very irregular hailstones.
Heat transfer from artificial hailstones
Authors: Bailey I. H. , Macklin W. C. 
Published: February 2007

AbstractThe rate of melting of realistically rough artificial hailstones in an airstream has been measured and the dependence of the rate of heat transfer on Reynolds number determined. The rates of heat transfer show a marked divergence from the values for smooth spheres as the Reynolds number increases from 104 to 2 × 105. The results indicate that the effective critical liquid water concentrations of large hailstones (diameters greater than 6 cm) are 1·2 to 3 times those previously computed.
Microbarographic oscillations produced by nuclear explosions as recorded in Great Britain and Eire
Authors: Mackinnon R. F. 
Published: February 2007

AbstractA summary is presented of previously unpublished microbarographic data associated with atmosphere thermonuclear bomb tests in the Marshall Islands and in the Soviet Union from 1954 to 1962. Some effects of winds upon atmospheric pressure waves are indicated through study of wind conditions over the paths of propagation and through comparison with reported Japanese data. It is shown that, as well as the speed of the waves, the maximum amplitudes of wave‐trains depend upon wind conditions so that estimates of the size of explosions must take into account prevailing winds. The possible usefulness of microbarograms in the study of upper atmospheric winds is indicated.
Some numerical experiments using a two‐level general circulation model
Authors: Davies D. J. , Davies D. R. 
Published: February 2007

AbstractA two‐level quasi‐geostrophic model, developed to probe into certain large‐scale features of the general circulation of the atmosphere, is discussed together with two main results of particular interest. Firstly, on averaging over longitude and over a typical cycle in eddy kinetic energy, the model indicates a functional dependence of meridional flux of zonal momentum on latitude which is approximately in step with the dependence of meridional temperature gradient on latitude. Although it is known that this type of model is not accurate in describing the motion of very long waves, the result gives some interesting theoretical support for one of the basic premises of the long time period average model of the general circulation discussed by Williams and Davies (1965). Secondly, the significance is clearly demonstrated of the particular functional forms chosen for the initial distribution of perturbation stream function values, as used in the past in a great deal of general circulation work. This is achieved by working from several initial distributions and noting that the ensuing differences in large‐scale characteristics are very clearly stamped on the flow for at least the thirty days of time integration considered in this paper. From the standpoint of calculating a ‘theoretical limit of predictability of the atmosphere’ these results can therefore be interpreted to indicate that the functional form assumed for the distribution of the initial perturbations could appreciably influence a calculation of this limit, although such calculations were not carried out in this paper. Several other results concerning the influence on these large‐scale characteristics of the forms adopted to describe vertical transfer of momentum and of total heating function are also discussed, together with the effects of introducing certain alternative computing schemes.
Momentum transport by gravity waves
Authors: Bretherton F. P. 
Published: February 2007

AbstractA review of theories concerning the propagation of internal gravity waves in a horizontally uniform shear flow concludes that an upward transport of horizontal momentum inevitably accompanies the generation of such waves in the atmosphere, the mean flow being affected only at precisely those levels where the waves are dissipated. If the mean wind depends on horizontal position there may be a continuous transfer of momentum from the waves to the mean flow during propagation. In the absence of intense clear air turbulence or a critical level where the intrinsic frequency vanishes, many waves propagate upwards to great heights, even if the mean wind is time dependent. Computations of the wave drag in a 19 m s−1 gradient wind over hilly terrain in north Wales show that on that occasion it amounted to 4 dyne cm−2, of which 3 dyne cm−2 probably acted on the atmosphere above 20 km.
The effects of spectral resolution on total ozone measurements
Authors: Vanier J. , Wardle D. I. 
Published: February 2007

AbstractThe effect of the finite width of the wavelength bands passed by spectrophotometers used to measure the total ozone overhead is discussed. For a Dobson spectrophotometer the effect is negligible. For a spectro‐photometer with wide slits, designed for use on a star, the effect is significant. For a filter instrument the effect is so large as to represent a serious obstacle to the use of the instrument, particularly if allowance is made for the effects of haze.
The spreading of accreted droplets
Authors: Macklin W. C. , Payne G. S. 
Published: February 2007

AbstractMeasurements of the spreading factor of accreted droplets (the ratio of the final radius to the initial radius) have been determined over a wide range of impact speeds and ice deposit temperatures for ambient temperatures of −11 and −22°C and droplet radii of 17 and 54μ. The spreading factors vary from 2 to 6 and depend primarily on the impact speed and deposit temperature.
An alternative procedure for the evaluation of a balanced wind
Authors: Woodroffe A. 
Published: February 2007

AbstractA numerical procedure is described for determining, in a barotropic model, the horizontal wind (V) from the field of geopotential height, based on the approximation d2 V/dt2 = 0. The technique used to solve the resultant simultaneous equations is outlined and some of the problems which were encountered in their solution are also mentioned. The approximation permits the evaluation of the geopotential height tendency and a comparison is made between barotropic forecasts based on this condition and on conventional barotropic and baroclinic numerical integrations.
Profile relationships: The log‐linear range, and extension to strong stability
Authors: Webb E. K. 
Published: February 2007

AbstractThe diabatic mean profile forms in the surface layer are studied, by applying analysis methods having high resolving power to data from O'Neill, U.S.A. (heights up to 6.4 m) and from Kerang and Hay, Australia (heights mostly up to 16 m).It is found, concordantly from the O'Neill and Australian data, that the log‐linear law is valid for z/L values between — 0.03 and + 1, which includes a small range of unstable and a surprisingly wide range of stable conditions. For all quantities studied (wind, potential temperature, and specific humidity), it is concluded that the Monin‐Obukhov coefficient α is near 4.5 in unstable and 5.2 in stable conditions, within a standard error of about 10 per cent. The ratios KH/KM and KW/KM evidently remain constant, equal to unity, over the whole of the log‐linear range (and somewhat beyond).In stable conditions, the log‐linear law implies that Ri approaches a critical value α−1, approximately 0.2, as z/L → ∞. However, at z/L a second régime sets in, in which the profiles are only quasi‐determinate, approximating, on the average, a simple logarithmic form (gradients proportional to z−1); this régime covers the range approximately 1 < z/L < (α + 1), i.e. (α + 1)−1 < Ri < 1. A third range of extreme stability, Ri > 1, is practically unrepresented in the data examined.The major part of the unstable range, for z/L < − 0.03, will be discussed in a later paper.
Transfer properties of the large‐scale eddies and the general circulation of the atmosphere
Authors: Green J. S. A. 
Published: February 2007

AbstractThe transfer of heat and momentum by motion on the scale of cyclone waves and long waves is deduced from a knowledge of their mechanics. The law of horizontal transfer of entropy is independent of notions of mixing but is similar to that for non‐isotropic diffusion. The law accurately represents the annual variation of heat‐flux in the Northern Hemisphere. Perturbation theory suggests realistic spatial variations for the transfer and provides a rational basis for calculating transfer coefficients which can then be used to find the flux of other conservative quantities. Most importantly the Equatorward flux of potential vorticity is well defined and is shown to determine the horizontal flux of momentum uv. The mean surface winds, and the mean meridional circulation (which is seen to be frictionally driven) are then determined. A model of the general circulation is defined by these properties, and this is integrated analytically for a simplified case and compared with motion observed in the Gulf Stream, the mesosphere, and dishpan experiments as well as the troposphere.
Fluctuations of horizontal wind speed near the ground in convective conditions
Authors: Coulman C. E. 
Published: February 2007

AbstractSimultaneous records of temperature fluctuations and wind speed at several heights have been obtained with instruments suspended from captive balloons flying 225 m above level, uniform land.Variations in the horizontal wind speed near the ground appear to be associated with bursts of temperature fluctuation at heights of more than about 100 m in a way which suggests that convective plumes, or ‘thermals,’ become organized within the lowest few metres of the atmosphere.
Electrification accompanying the freezing of water
Authors: Dawson R. , Hutchinson W. C. A. 
Published: February 2007

Abstract75‐ml samples of de‐ionized, distilled water were frozen and electric potential differences between similar electrodes in the ice and water respectively were measured as functions of time, rate of freezing and temperature differences within the ice layer. The charge separation at the ice/water interface caused by selective rejection of ions always exceeded that due to temperature gradients within the ice at freezing rates greater than 10 μm s−1.
The variation of the electric field after lightning and the conductivity within thunderclouds
Authors: Illingworth A. J. 
Published: February 2007

AbstractIt has been found that the rate of growth of field following a close lightning discharge is explicable in terms of the regeneration of the dipole by a constant current and a charge loss governed by the fair weather conductivity at the height of the charge. The recovery may be influenced by local point discharge after large field‐changes, but the presence of a core of high conductivity within the cloud need not be invoked. The recovery curves from close flashes are found to be rather irregular and no really useful information concerning the currents generating the dipole of the thunderstorm can be derived from them. As the distance of the storm increases then the recoveries become much more rapid and of reproducible shape. It is suggested that after the discharge the re‐arrangement of the space charge existing because of the conductivity gradient in the atmosphere is responsible for the change of the field observed. Some numerical work gives fair agreement with the observed functional dependence of the initial rate of recovery on the size of the field change. These distant recoveries are the response of the conducting atmosphere to the field change, and can give no useful information about the thunderstorm itself.
Measurements of submillimetre wavelength radiation emitted by the stratosphere
Authors: Harries J. E. , Burroughs W. J. 
Published: February 2007

AbstractObservations have been made of the submillimetre wavelength radiation emitted by the lower stratosphere, using techniques of Fourier transform spectroscopy, while flying in a Comet 2E aircraft. Using the method of phase‐modulation high quality spectra have been obtained at several altitudes over the spectral range 20 to 66 cm−1, and these have enabled identification of many emission lines due to O2 and O3, in addition to those of H2O. Also several unidentified emission lines have been observed. The meteorological applications of this spectroscopic technique are considered. In particular, a direct method of comparing the emission of ‘strong’ water‐vapour and oxygen lines enables a calculation of mixing ratio of water vapour in the stratosphere to be made, and a value of (2.1 ± 0.3) × 10−6 g/g is derived above an altitude of 12.2 km. A similar comparison for ozone has given an integrated concentration of 0.35 ± 0.10 cm atm in the vertical path above the observer. The merits of these observations in measuring stratospheric mixing ratios are discussed with respect to alternative techniques, in particular with reference to balloon‐borne studies.
The albedo of a pine forest
Authors: Stewart J. B. 
Published: February 2007

AbstractThe albedo of a pine forest was measured for a total of 243 hours during the summer of 1970 by pairs of Kipp solarimeters whose output was recorded by a computer controlled data acquisition system. It was found that the mean albedo was 9.1 per cent. On cloudless days there was a pronounced dependence of albedo on solar zenith angle; however, on cloudy days there was little variation. The effect on the albedo of the wetness of the canopy was less than one per cent except at large solar zenith angles. The mean albedos for June and December were calculated and found to be 8.9 and 11.7 per cent respectively.
The surface drag contribution to the depth of Atlantic, and European, depressions
Authors: Dodds I. 
Published: February 2007

AbstractEstimates are made of the forced ωF‐components arising from surface frictional inflow within the circulation of an ‘average’ Atlantic and an ‘average’ European depression. When allowance is made for the high curvature flow by the inclusion of a centripetal acceleration term in the equation of motion, it is found that the ωF‐contribution at the top of the boundary layer, is much the same in each case. The quasi‐geostrophic ω‐equation is solved to obtain the three‐dimensional ωF‐field accompanying the average depression. This gives a value of ∂ωF/∂p at the centre of the depression, and using this in the geostrophic vorticity equation it is found that surface friction makes a positive contribution of about 4 mb day−1 to the central pressure tendency in each case.
The stability of charged drops in uniform electric fields
Authors: Brazier‐Smith P. R. 
Published: February 2007

AbstractStability criteria of charged drops levitated by uniform electric fields are determined by assuming that the drops possess spheroidal equilibrium shapes and that the equations of equilibrium are satisfied at the two poles and the equator. The stability criteria were also determined by the more precise method prescribed by Brazier‐Smith (1971). Comparison of the results of the two methods indicates that the spheroidal assumption, which was applied with considerable success to study the stability of uncharged drops, cannot be applied to cases in which the drops are charged.
The vertical propagation of angular momentum in the west wind belts
Authors: Clarke R. H. 
Published: February 2007

AbstractBoundary layer data from the Wangara expedition show that, at a point in the mean winter west wind belt (but near its equatorward limit), eddies on the synoptic scale (periods greater than a day) transferred westerly momentum upward. Except in the lowest 500 m, this upward tranfer predominated over downward fluxes due to micro‐scale (periods less than 2 hours) and meso‐scale (2 ‐ 24 hours) eddies, the latter transfers being very small. The effect of ageostrophic motions, due to accelerations, on this transfer was negligibly small.A characteristic circulation, relative to synoptic systems, in a vertical zonal plane, performing the vertical transfer of westerly momentum, has been deduced.The eddy flux of angular momentum, in the middle latitude boundary layer between 500 and 1,700 m appears to be directed up the angular momentum gradient, both horizontally and vertically, and, at all levels, down the horizontal gradient of angular velocity.An argument is presented to show that the intensity of circulation in the Ferrel cell may be greater than is usually estimated, the maximum absolute value of the stream function (except for the Northern Hemisphere in summer), being normally at least about 30 × 1012 g s−1.
Aircraft measurements of dissipation of turbulent kinetic energy
Authors: Taylor R. J. 
Published: February 2007

AbstractFifty values of the rate of dissipation of turbulent kinetic energy, ε, deduced from spectra of vertical air velocity component made from an aircraft are presented. While generally in the range of values found by other authors the distribution of ε with height shows a good deal of scatter. This can in large measure be resolved by grouping the observations according to site roughness, season and wind speed, thus allowing for the varying contributions to ε of the wind‐shear and buoyancy‐force terms.The characteristic decay time of the turbulence (defined as the variance of vertical velocity divided by ε) increases consistently as the square root of height.
Diurnal variation of temperature and wind in the equatorial stratosphere
Authors: Hamilton R. A. , Shearman R. J. 
Published: February 2007

AbstractRocket soundings were made at Gan (0°41′S, 73°09′E) after sunset and before sunrise to determine the change of temperature and wind during the night. The soundings showed that the change of temperature varied with height, being positive around 54 km, negative around 44 km, and mainly positive between 30 and 40 km, in general agreement with Lindzen's tidal theory. The zonal wind also showed a tidal variation. An analysis of day and night rocket soundings at Ascension Island (07°59′S, 14°25′W) indicates that the winds show a tidal variation, but the heights of the isobaric surface in the stratosphere are always a maximum around noon, suggesting an error in the temperature measurements due to solar radiation.