Seasonal and diurnal variability of pressure fluctuation in the infrasound frequency range observed in the Czech microbarograph network
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Infrasound environments in the Czech microbarograph network were studied. Reference Fourier amplitude spectra were calculated from data measured at three microbarograph sites of the network in May 2011-April 2012; directional analysis of infrasound arrivals in the frequency band 0.15-0.4 Hz was performed for the microbarograph array at Panská Ves in May 2014-April 2015. Diurnal, seasonal and site-to-site variability of the reference spectra was evaluated. Site-to-site variability is influenced by the location of the respective sensors in the open air and inside the observatory buildings and by local noise phenomena like wind turbines. Diurnal variability is well developed in summer with maximum ambient noise levels during the daytime and minima at night. Seasonal variability is observed at night with maxima in winter and minima in summer. Wind and wind eddies seem to be an important source of ambient noise in measurements in the Czech microbarograph network. A distinct spectral peak occurs near 0.2 Hz with amplitudes by about one order of magnitude higher in winter than in summer. Its seasonal variability is related to seasonal propagation of microbaroms from the source region in the Northern Atlantic.
Keywordsinfrasound environments Czech microbarograph network seasonal and diurnal variability
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- Assink J.D., Waxler R., Smets P. and Evers L.G., 2014. Bidirectional infrasonic ducts associated with sudden stratospheric warming events. J. Geophys. Res., 119, 1040–1153, DOI: 10.1002/2013JD021062.Google Scholar
- Brázdil R, Štekl J., Budíková M., Dobrovolný P., Fišák J., Kolár M., Prošek P., Sokol Z., Štepánek P., Štepánková P. and Zacharov P., 1999. Klimatické pomery Milešovky (Climate on Milešovka). 1st Edition. Academia, Prague, Czech Republic (in Czech).Google Scholar
- Garces M., Willis M. and Le Pichon A., 2010. Infrasonic observations of open ocean swells in the Pacific: Deciphering the song of the sea. In: Le Pichon A., Blanc E. and Hauchecorne A. (Eds.), Infrasound Monitoring for Atmospheric Studies. Springer-Verlag, Berlin, Germany, 29–75.Google Scholar
- Le Pichon A. and Cansi Y., 2003. PMCC for infrasound data processing. InfraMatics, 2, 1–9.Google Scholar
- Le Pichon A., Vergoz J., Blanc E., Guilbert J., Ceranna L., Evers L. and Brachet N., 2009. Assessing the performance of the International Monitoring System’s Infrasound network: Geographical coverage and temporal variabilities. J. Geophys. Res., 114, D08112, DOI: 10.1029/2008JD010907.CrossRefGoogle Scholar
- Nový R., 2009. Hluk a Chvení (Noise and Vibrations). 3rd Edition. Ceské vysoké ucení technické v Praze (Czech Technical University in Prague), Prague, Czech Republic (in Czech).Google Scholar
- Smets P.S.M. and Evers L.G., 2014. The life cycle of a sudden stratospheric warming from infrasonic ambient noise observations. J. Geophys. Res., 119, 12084–12099, DOI: 10.1002/2014JD021905.Google Scholar