Papers in Meteorology and Geophysics
Online ISSN : 1880-6643
Print ISSN : 0031-126X
ISSN-L : 0031-126X
Volume 35, Issue 4
Displaying 1-3 of 3 articles from this issue
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  • Part 2: in Continuous Form
    Motohki Ikawa
    1984 Volume 35 Issue 4 Pages 169-180
    Published: 1984
    Released on J-STAGE: March 09, 2007
       A method of statistical objective analysis in discrete form (Ikawa, 1984b) is extended to a method in continuous form. Analysis equations are integro-differential equations, where their integral kernels are inverse covariance matrices.
       Comparison between the method and conventional variational objective analysis is made. Analysis equations of variational objective analysis are differential equations, while those of the method in this paper are integro-differential equations. If the method uses diagonal covariance matrices with no correlation with data on other locations, analysis equations of the method reduce to those of variational objective analysis.
       The spectral representation of analysis equations is presented. The response function of the analysis scheme as a linear filter is expressed in terms of spectral representations of linear constraint and covariance matrices. Some examples of application of spectral representation of analysis equations are shown. The roles of linear constraint and covariance matrix is made clear in the wave number domain.
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  • Takayo Matsuo
    1984 Volume 35 Issue 4 Pages 181-197
    Published: 1984
    Released on J-STAGE: March 09, 2007
       The periodical oscillations contained in time variations of meteorological elements at five weather stations in the extratropical and subtropical regions of Japan were examined by spectrum analyses. The meteorological elements were air temperature, pressure, wind, total cloud amount, and flux of global solar radiation in 1977. The analyses showed that about 30-day and 50-day period mode oscillations, and about 40-day period mode oscillation appeared persistently in the time variations in the extratropical and the subtropical region, respectively. In addition, about 70-day period mode oscillation was sometimes seen in both regions, but we cannot determine from the present analyses whether or not a disturbance with a period of about 70 days is definitely existent. Comparison of time variations among the elements at a station indicated that the time variations were associated with each other and the phenomenon was concurrent. It is suggested that the time variations are accompanied by some large-scale tropospheric oscillation. The present study gives a positive support to the existence of about 30 to 50-day period oscillation around Japan.
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  • Akio Yoshida, Shin-ichi Nihei, Kanefusa Ohta, Shinji Susukida
    1984 Volume 35 Issue 4 Pages 199-207
    Published: 1984
    Released on J-STAGE: March 09, 2007
       The relationship between the ground strain change and the water level variation in the bore-hole of the volumetric strain meter is investigated. At Shizuoka, the strain appears in the dilatational sense with rise of water level, whereas at Aziro, uplift of the groundwater table results in contraction.
       The latter sense of correlation can be attributed to the increase of groundwater loading on the local rocks. On the other hand, the correlation as observed at Shizuoka is explained by the increase of pore pressure due to rising of groundwater level, which decreases stress in the rock surrounding the strainmeter and causes volumetric strain expansion.
       The theoretical correction of the observed strain for variation of the underground water table is difficult, because the water level in the bore-hole does not necessarily represent the water table which controls the local stress affecting the strainmeter.
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