ISSN:0035-9009    

DOI:10.1002/qj.49708335702

出版商:John Wiley&Sons, Ltd    

年代:1957

数据来源: WILEY

摘要:

AbstractSurface‐wind observations in the Northern Hemisphere are analysed and fields of mean meridional and zonal motion obtained. From these, profiles of mean meridional motion as a function of latitude are deduced. The results are consistent with a direct meridional circulation in low latitudes and an indirect circulation in mid‐latitudes, both attaining speeds of 1 to 2 m/sec at the surface. This scheme is found to be consistent with a decrease of upward flux of westerly momentum with height (convergence) in the surface layers in low latitudes and a decrease of downward flux in mid‐lati

ISSN:0035-9009    

DOI:10.1002/qj.49708335703

出版商:John Wiley&Sons, Ltd    

年代:1957

数据来源: WILEY

摘要:

AbstractThe paper gives an account of Disturbance Lines (D/Ls) observed on the charts of the forecasting office of the Ghana Meteorological Department at Accra in 1955. The progress of one of the larger D/Ls is shown to indicate the extensive area affected in some cases. The origins of D/Ls, their movement, distribution, and other characteristics, are described. The importance of the phenomenon in the local weather is shown by the proportion of the monthly rainfall due to D/Ls at four Ghana stations. Emphasis is placed on the nature of the D/L as a disturbance which moves through the atmosphere, transferring convective energy to other forms, notably horizontal kinetic energy, in an ordered manner.

ISSN:0035-9009    

DOI:10.1002/qj.49708335704

出版商:John Wiley&Sons, Ltd    

年代:1957

数据来源: WILEY

摘要:

AbstractAn account is given of laboratory measurements of absorption by the 9.6 μ band of ozone using dry air as the foreign gas. The experimental results for the band area, Ar, are tabulated for ozone amounts up to 1.5 cm STP and pressures from 10 to 760 mm Hg at a temperature of 20°C; the slit width is 6.5 cm−1. An empirical formula for Aris given. The best fit is obtained with slightly modified values of the ultra‐violet absorption coefficients determined by Vigroux (1953), when the standard error in band area is 2.4 per

ISSN:0035-9009    

DOI:10.1002/qj.49708335705

出版商:John Wiley&Sons, Ltd    

年代:1957

数据来源: WILEY

摘要:

AbstractDew formation on short grass has been studied with a balance, recording weight of condensation, and with filter papers to absorb moisture. Three regimes are distinguished: in the first, daytime evaporation continues and the grass remains dry; in the second, the surface continues to lose weight but the grass becomes wet owing to the partial condensation of water vapour evaporating from the soil; in the third, this loss of weight ceases or there is an increase in weight attributed to condensation of atmospheric water vapour. A distinction is therefore made between ‘distillation’ of water vapour from soil to grass (1–2 mg cm−2hr−1) occurring on very calm nights through a laminar layer with a transfer coefficient approaching the molecular value; and ‘dewfall,’ the turbulent transfer of water vapour from the atmosphere, negligible when the wind at 2 m falls below 0.5 m/sec but reaching 3–4 mg cm−2hr−1with stronger winds. This distinction is supported by analysis of the surface heat‐budget. On windless nights, since heat flux from the soil and net radiative loss were almost equal, the transfers of sensible and latent heat from the atmosphere were negligible and distillation was of much greater importance than dewfall. Implications for taller crops and warmer climates a

ISSN:0035-9009    

DOI:10.1002/qj.49708335706

出版商:John Wiley&Sons, Ltd    

年代:1957

数据来源: WILEY

摘要:

AbstractThe temperature attained in the reversible and pseudo‐adiabatic expansion of air saturated with respect to liquid water is taken as a reference; the temperatures attained in the following expansions from the same initial state are then compared with it: (a) the ice‐saturation pseudo‐adiabatic process (b) the water‐saturation adiabatic process (c) the ice‐saturation adiabatic process.The results of these comparisons are summarized in Figs. 1 to 5 of this paper.Similarly, the cloud virtual temperature, the virtual temperature adjusted for the weight of suspended particles, attained in water‐saturation adiabatic expansion, is compared with that attained in water‐saturation pseudo‐adiabatic expansion; Fig. 6.The implications of these calculations for the properties and behaviour of cumulus are

ISSN:0035-9009    

DOI:10.1002/qj.49708335707

出版商:John Wiley&Sons, Ltd    

年代:1957

数据来源: WILEY

摘要:

AbstractWaves recorded in the decay area by a ship‐borne wave recorder on o.w.s.Weather Explorerare compared with estimates of waves in the generating area. By restricting attention to the wave energy contained within one‐second wave period intervals, it is possible to eliminate the effect of dispersion and to study the decrease in height due to loss of wave energy and the broadening of the wave front. While it is not possible to give an accurate assessment of the relative magnitude of these effects, the formula obtained in the case of calm conditions or following winds in the decay area isHT/H °T= (300/R)1/2, whereRis the distance of the recording point from the centre of the generating area. This formula does not depend on wave period and following wind speed, and suggests that the effect of broadening the wave front is the more important. It has been used successfully in predicting wave heights and periods at Casa

ISSN:0035-9009    

DOI:10.1002/qj.49708335708

出版商:John Wiley&Sons, Ltd    

年代:1957

数据来源: WILEY

摘要:

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 calcul

ISSN:0035-9009    

DOI:10.1002/qj.49708335709

出版商:John Wiley&Sons, Ltd    

年代:1957

数据来源: WILEY

摘要:

AbstractA new determination of the absolute value of the absorption coefficient of ozone at 3021 Å is described. The value obtained for the decimal absorption coefficient, measured at 20°C, is 3.310 ± 0.009 (cm STP)−1. This figure is in excellent agreement with the value for this wavelength obtained by Vigroux (1953) and may be used with confidence in meteorological applicat

ISSN:0035-9009    

DOI:10.1002/qj.49708335710

出版商:John Wiley&Sons, Ltd    

年代:1957

数据来源: WILEY

摘要:

AbstractThe information of the vertical distribution of atmospheric ozone obtainable from measurements of scattered sunlight received from various directions in the sky is considered. It is shown that observations in a particular direction in the sky could replace, but would not supplement the customary zenith sky observations, except in high latitudes at certain seasons of the year. Observations in various directions in the sky would be equivalent to zenith sky observations made throughout the day.

ISSN:0035-9009    

DOI:10.1002/qj.49708335711

出版商:John Wiley&Sons, Ltd    

年代:1957

数据来源: WILEY