Journal of the Meteorological Society of Japan. Ser. II
Online ISSN : 2186-9057
Print ISSN : 0026-1165
ISSN-L : 0026-1165
Volume 50, Issue 1
Displaying 1-6 of 6 articles from this issue
  • with special emphasis on the relation among the supply from the sea surface, the convective transfer and the synoptic weather situations
    K. Ninomiya
    1972 Volume 50 Issue 1 Pages 1-17
    Published: 1972
    Released on J-STAGE: May 27, 2008
    JOURNAL FREE ACCESS
    The warm sea current Kuroshio is very strong in the East China Sea. During the winter season the polar-continental air-mass breaks out over the warm sea so that a large amount of sensible heat and water-vapor are supplied from the ocean and produce a remarkable air-mass modification.
    The heat and water-vapor budget over the East China Sea is analysed with special emphasis on the relations among the energy supply, the convective transfer of heat energy and the synoptic weather situations in February of 1968 by using aerological data.
    The heat and moisture supply from the sea surface are also evaluated by using the bulk method basing on marine observation data for the February of 1966, 1967, and 1968.
    The amount of the sensible heat supply and the evaporation are estimated to be 300 ly•day-1 and 10 mm day-1 respectively both by budget calculations and by bulk method.
    During the period of the analyses in February 1968, predominant synoptic-scale disturbances developed with a period of about 4-day over the East China Sea region. The amount of the energy supply from the sea increases remarkably under the situation of the polar-air outbreak.
    The terms concerning the convective transfer of heat and moisture are introduced in the largescale budget equation and the magnitudes of the transfer across various levels are estimated.
    It is shown that the magnitude of the convergence of the horizontal water-vapor flux in the lower layer and that of the convective transfer of heat energy increases remarkably when the cyclone developes in the East China Sea region. It is suggested that the convergence of the water-vapor flux in the lower troposphere would play an important role, as well as the energy supply from the ocean, for the development of the cyclone in the East China Sea region in winter season.
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  • Isao Kubota
    1972 Volume 50 Issue 1 Pages 18-36
    Published: 1972
    Released on J-STAGE: May 27, 2008
    JOURNAL FREE ACCESS
    Each component of both energy budget equations for the atmosphere and for the surface layer of the earth are parameterized by functions of the incident solar radiation at the top of the atmosphere, the temperature at the mid-atmosphere (500mb level) and at the earth surface. The parameterization includes the following two assumptions needful to simplify the model: (1) The condensation heat released into the atmosphere minus the vertically integrated divergence of total energy flux in the atmosphere is constant. (2) Time change of the heat energy stored in the earth surface layer is proportional to time change of the earth surface temperature, where the proportional coefficients are different between the hydrosphere and the lithosphere.
    Simultaneous energy budget equations for the atmosphere and for the earth surface layer yield a non-homogeneous, one-order, linear ordinary differential equation of the temperature at the 500mb level or at the surface with respect to time. A homogeneous term of the equation is a function of the incident solar radiation at the top of the atmosphere. Integrating the equation with respect to time from 0°K for an initial value of the temperature at the 500mb level or the surface, the temperature rises gradually with the date of the year and comes to have seasonal variations after several years integration. Inspite of many rough assumptions, the computed seasonal variation of the temperature shows approximate agreement with the observation at each cases following respective the 500 mb level and the surface over land and over sea.
    The responses of the temperature at the 500mb level and the surface are investigated over sea and over land against variation of cloud amount, surface albedo and sudden rise of the surface albedo, which follows the year's first snow covering over ground.
    The phase lag in the seasonal variation of temperature against outer atmospheric solar radiation is analytically solved. The results show that the phase lag of temperature at the surface against outer atmospheric solar radiation depends on the oceanicity and is independent of the surface albedo. The phase lag at the 500mb level depends on the oceanity and even the surface albedo, which is larger over higher latitudes. Namely, the phase of the 500mb level temperature retards much more over lower latitudes, where the albedo is smaller than over higher latitudes.
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  • Y. Ookochi
    1972 Volume 50 Issue 1 Pages 37-48
    Published: 1972
    Released on J-STAGE: May 27, 2008
    JOURNAL FREE ACCESS
    A finite difference scheme is proposed in performing the numerical time integration over the domain which consists of two different grid systems. The scheme employs the flux method in space and Euler backward method in time.
    In order to examine the proposed scheme, numerical experiments are conducted by applying the primitive equation model to an incompressible, homogeneous atmosphere contained in a channel with the free surface. As the coarse mesh size 600km is taken up and as the fine mesh a half of the coarse grid interval (300km) is adopted. The present scheme combines both grid systems, minimizing the occurrence of noise motions at the boundary between different grid systems.
    Results of the numerical experiment show smooth patterns throughout 96 hours for an initial field consisting of two wave patterns. The main conservative quantities such as mass, total energy, etc. well keep its initial value during the whole computation.
    As far as the present simple experiment is concerned, the combined grid system results in a calculated pattern just like as a composite of the results obtained by using uniformly the coarse grid net alone and the fine grid net alone. Although the present experiment is limited, we may expect the results as a first step towards the nesting of the fine grid subdomain in the coarse grid net.
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  • S.B. Idso, K.R. Cooley
    1972 Volume 50 Issue 1 Pages 49-58
    Published: 1972
    Released on J-STAGE: May 27, 2008
    JOURNAL FREE ACCESS
    An equation was derived to predict the influence upon net radiation measurements of the effects of a net radiometer's shadow upon the underlying surface. The predictions of the equation were verified by two independent experiments. It was found that for a miniature net radiometer (6cm diam.) operated over dry, bare soil on a cloudless day, that the surface induced effects do not become significant until the radiometer is lowered below a height of 20cm. The optimum level of operation in light of this effect and that of the intervening layer of air between the net radiometer and the soil appeared to be 25±5cm.
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  • Shozo Ito
    1972 Volume 50 Issue 1 Pages 59-64
    Published: 1972
    Released on J-STAGE: May 27, 2008
    JOURNAL FREE ACCESS
    The average dispersion rate of atmospheric diffusion from a fixed point can be expressed as a function of the traveling time and the observation time using a spectral representation for the behavior on the smoke plume.
    A spectral form for the eddy diffusivity in the cross-wind direction leads to a conclusion of depending upon the traveling time and the sampling period for a time mean concentration.
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  • Hiroki Kondo, Ryuji Kimura, Sachiko Nishimoto
    1972 Volume 50 Issue 1 Pages 65-69
    Published: 1972
    Released on J-STAGE: May 27, 2008
    JOURNAL FREE ACCESS
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