ISSN:0035-9009    

DOI:10.1002/qj.49709139002

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractKinetic energy in middle and high latitudes, at levels above 20 km, increases throughout winter until the final warming, which supports the view that frictional dissipation is dynamically unimportant at these levels. A climatology of wave disturbances is presented for the years 1958‐61, little support being found for a special role for bipolarity in instability. Comments are made on the pronounced layer structure shown in the wind profiles and the regular ozone‐sonde records. It is suggested that the next stages of research in stratospheric meteorology should be directed towards the layer struct

ISSN:0035-9009    

DOI:10.1002/qj.49709139003

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

ISSN:0035-9009    

DOI:10.1002/qj.49709139004

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

ISSN:0035-9009    

DOI:10.1002/qj.49709139005

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractIn order to improve the accuracy of the fundamental data required for calculations of the photo‐chemical production of ozone, the intensity of the solar ultraviolet light, λ ≈︁ 2100 Å, which penetrates to the lower stratosphere, has been measured with the sun directly overhead. The radiation was first detected at the 196 mb level where the flux was 2 × 108photons cm−2sec−1and two of three ascents reached the 6 mb level where the flux was 1.2 × 1013ph cm−2sec−1. The results of calculations of the expected intensity at different levels are also presented and adjustments to the data used are found to be necessary in order to obtain agreement with

ISSN:0035-9009    

DOI:10.1002/qj.49709139006

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractWhen pure uniform ice specimens of different temperatures are brought into gentle contact for times ranging from 10−3to 5.10−2sec and are then separated, the charge transfer is a maximum for a contact time of about 7.5 × 10−3sec and is in agreement with the equations of Latham and Mason (1961a). With ice of higher conductivity the maximum charge transfer occurs after smaller contact times.For impact velocities less than about 7.5 cm sec−1the charge transfer is in agreement with the theory but above this value the charge transfer increases linearly with impact velocity. The charge transfer is also enhanced, by as much as an order of magnitude, if the ice specimens are tapered. A tentative conclusion to be drawn from these experiments is that the value of 5 × 10−4e.s.u., measured by Reynolds, Brook and Gourley (1957) for the charge transfer per collision between an ice crystal and a warmer artificial hailstone, which is sufficient to generate charge at a rate required by a tenable theory of thunderstorm electrification, may be explicable in terms of the temperature‐gradient effect.When steady temperature gradients are applied to uniform specimens of pure ice the potentials developed across the ice are unaffected by the pressure to which the ice is subjected. The application of steady temperature gradients to tapered ice specimens produces potentials which are up to an order of magnitude greater than predicted

ISSN:0035-9009    

DOI:10.1002/qj.49709139007

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractEquations are constructed to represent quasi‐stationary mean flow of momentum and heat on a spherical earth, averaged over a long period of time such as a year and over latitude circles. The crucial shearing Reynolds stress associated with meridional transfer of zonal velocity is assumed to depend linearly on a product of the earth's angular velocity, Ω, and the meridional gradient of mean temperature; the shearing stresses associated with vertical transfer of zonal velocity and of meridional velocity are assumed to depend linearly on the vertical gradients of zonal and of meridional mean velocities respectively, and the mean eddy transfer of heat along a meridian is assumed to depend linearly on the mean meridional temperature gradient. All proportionality coefficients are taken to be independent of latitude. Two forms are assumed for the non‐adiabatic atmospheric heat source function,Q, used in the thermodynamic equation. In the first caseQis assumed known (from analyses of observations) as a function of height and latitude. In the second case,Qincorporates a heating term which is partly controlled by the model itself and represents some of the characteristics of sensible and latent heat transfer. A solution of the basic equations is obtained in both cases in the form of double expansions in powers of two parameters, one depending on Ω and the other on ΔT, the mean annual temperature difference between equator and pole. The solution is evaluated using Fourier techniques.The series expansions are found to be reasonably convergent for realistic values of the various parameters involved, three terms only being required in the ΔT expansion and five terms at most in the Ω expansion, but extensive numerical evaluation by digital computer is involved: the region considered is bounded by the tropopause and lies between the equator and 70° latitude. The computed zonal velocity has the characteristic east‐west variation with latitude and a broad band maximum of 19 m sec−1and the meridional velocity the characteristic tricellular structure. A poleward eddy angular momentum flux and polar inversion are predicted.The results, through verification of the postulates, add support to the Rossby view of the general circulation in which the cyclonic‐scale eddies act to release potential energy of the atmosphere to supply their own kinetic energy and form the mean zonal kinetic energy. They further indicate the value of the reconstructed ‘austausch’ approa

ISSN:0035-9009    

DOI:10.1002/qj.49709139008

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractAn attempt is made to obtain a coherent picture of the extent and mode of operation of the ‘southern oscillation.’ This term is used here, following Sir Gilbert Walker, to describe a standing fluctuation of opposed pressure anomalies in both eastern and western hemispheres. The existence of this opposition has been verified, using more recent data, for stations in the Indian and Pacific Ocean regions; results show the oscillation was less marked in recent decades.The representativeness and physical meaning of the index devised by Walker to characterize the state of the oscillation are considered. The geographical extent of the phenomenon is examined using correlation and regression charts of pressures with Walker's index. The temperature and rainfall anomalies associated with it may be derived qualitatively from the pressure anomalies.Recent data are used to verify persistence and lag correlations between station pressures; while there has again been some decline, the lag correlations of elements with previous South America pressures still hold good. The decline in these various quantities is indicative of a minor secular change commencing in the 1920's, which is also evident in a decrease in the variability of pressure.What ‘periodicities’ appear to exist in elements affected by the southern oscillation may well be an outcome of sampling fluctuations in (often persistent) random series. This is suggested by the variety of supposed ‘periods’ reported, and their evanescence in space and time. An example of this evanescence in time is provided from the Darwin pressure record.A mechanism for the oscillation is proposed in terms of variations in a direct toroidal circulation between warmer eastern and cooler western hemispheres. These variations are attributed, (following a model by Palmer of the synoptic climatology of the tropical Pacific) to variations in the south‐east trades in the South Pacific and the consequent variations in cyclonic vortex generation in the West Pacific. The persistence of anomalies is then due to the extent of ocean areas in the south‐east Pacific where the sea temperature is lower than the air temperature. The lag correlations observed may be due to this persistence and to a transmission of anomalies along the trades through air

ISSN:0035-9009    

DOI:10.1002/qj.49709139009

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractAn index is derived for the intensity of turbulence in a sloping baroclinic layer. Preliminary estimates of this index from ordinary meteorological information suggest that the index is proportional to turbulent energy and that it discriminates better between regions of varying intensity than vertical wind shear or Richardson number. An exact test, however, would require more detailed synoptic information than is usually available.

ISSN:0035-9009    

DOI:10.1002/qj.49709139010

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractSome simple transformation properties of the diffusion equation that has been classically used to describe turbulent transport in the atmosphere are briefly examined. The essential tensorial nature of the eddy diffusivity is emphasized and it is concluded that the standard form frequently adopted for the diffusion equation in the meteorological literature cannot be generally valid.

ISSN:0035-9009    

DOI:10.1002/qj.49709139011

出版商:John Wiley&Sons, Ltd    

年代:1965

数据来源: WILEY