Short review and recent results on microseisms

Abstract

Abstract. This paper endeavours, mostly in a bibliographical manner, to show the place of meteorological microseims among the whole of geophysics. Relations with swell are mentioned with their theoretical and practical consequences for the properties of both phenomena, and the work of members of the International Commissions on Microseisms is summarized, covering velocity and bearing of the waves, spectral analysis, relation with atmospheric circulation, and world-wide extension of these researches since the I.G.Y. In a recent project, undecennial variation of yearly means of microseismic disturbance, the maximum of which often occurs 2-3 years after sunspot maxima, is investigated using data from several stations. A similar variation is therefore inferred for atmospheric cyclones, and the brightness of other planets seems to vary in the same way. Changes in the solar constant are suggested as the physical influence responsible, and new recording devices are proposed to follow on an absolute scale the future behaviour of such an index of atmospheric disturbances.

Modeling Microseism Generation by Inhomogeneous Ocean Surface Waves in Hurricane Bonnie Using the Non-Linear Wave Equation

“…To determine the microseisms received by a sensor either in the ocean or in the earth's crust, the Green function of Equation (38) must be calculated. It has been shown both theoretically [10,14] and experimentally [4,[33][34][35][36][37] that microseisms propagate as Rayleigh waves along the sea floor.…”

“…It has been shown both theoretically [10,14] and experimentally [4,11,[33][34][35][36][37] that microseisms propagate as Rayleigh waves along the sea floor. Here we develop a normal-mode model for the propagation of Rayleigh waves along the seafloor assuming a water depth that changes with range.…”

Microseismicity, meteorology and the solar cycle

“…Bernard concluded by ascribing the microseismic agitation to the action of the swell at its point of origin [4]. Microseisms consist mostly of Rayleigh waves, which propagate in the crust with a velocity varying from 1 to 3 km/s, while the swell propagates in the ocean with a velocity of about 60 km/ h (or 0.017 km/s) [9].…”