An attempt to detect atmospheric free oscillations by a new array deployment of micro-barometers

网络建设（1）我们将微型气压计系统的10 MHz时钟替换为50 MHz时钟，以提高分辨率，特别是在较高频率方面。我们还开发了一个遥测数据传输系统，使我们能够检索网络数据的PC在手边。(2)我们在关东东海地区的14个网络站点中安装了该系统。，目前正在正常运行。由于系统设计的重大变化，目前可用的数据量没有原先预期的那么大。(3)我们检查了每个站的气压波动噪声频谱，发现了一种奇怪的气动声学震颤行为。我们探测到1- 5 mHz的空气重力波，它以60 m/s的速度自西向东传播。(4)我们总结了2007年初在希腊召开的国际会议上所报告的观测结果。数据分析和理论分析的结果（1）我们建立了一个激发模型，可以解释观测到的地球与大气之间的自由振荡共振现象，在此基础上，对大气自由振荡的压力幅值进行了估计，证明了探测的可行性。(2)通过对IRIS地震图的分析，表明背景自由振荡的激发源位于太平洋。源头季节性移动。这些来源不仅限于浅海，还应延伸到深海平面。(3)我们在日本的倾斜仪网络数据中检测到背景Love波。Love波与Rayleigh波的动能比约为1。海洋-大陆边界的背景波最强，其次是深渊位面，大陆最弱。(4)我们开发了一个激发模型，将背景Love和Rayleigh波归因于亚重力波的地形耦合，有效地产生作用于假定海底地平线的切向应力。

Network Construction(1) We replaced a 10 MHz clock of our micro-barometer system with a 50 MHz clock to increase resolution especially on a higher frequency side. We also developed a telemeter data-transmission system which enabled us to retrieve network data by PC at hand.(2) We installed the system at each of 14 stations of our network in the Kanto-Tokai districts. , which is now in routine operation. The amount of the data now available is not as large as originally anticipated because of the compelling change of the system design.(3) We examined the noise spectrum of air pressure fluctuation at each station and found a strange behavior of aero-acoustic tremor. We detected aero-gravity waves at 1-5mHz propagating from the west to east at a speed of 60 m/s.(4) We summarized the observational results obtained by the beginning of 2007, which were reported at an international conference in Greece.Results from Data Analyses and Theoretical Analyses(1) We developed an excitation model that can explain the observed resonance phenomenon of free oscillations between the solid Earth and the atmosphere, based on which we estimated the pressure amplitudes of atmospheric free oscillations to show that the detection is feasible.(2) We analyzed the IRIS seismograms to show that the excitation source of background free oscillations lies in the Pacific. The source moves seasonally. The sources are not limited to shallow seas but should extend to abyssal planes.(3) We detected background Love waves from tiltmeter network data in Japan. Kinetic energy ratio of Love to Rayleigh waves is approximately one. The background waves are strongest from ocean-continent borders, next from abyssal planes and weakest from continents.(4) We developed an excitation model attributing background Love and Rayleigh waves to topographic coupling of infragravity waves that effectively generates tangential stress acting on the presumed seafloor horizon.