Muschinski, AndreasSubramanian Ananthanarayanan, Ganesh Kumar2024-04-262009-08-3120092009-0910.7275/983896https://hdl.handle.net/20.500.14394/47241In this thesis, the performance of absolute quartz-crystal barometers is presented, and their ability to measure, with sub-microbar precision, atmospheric pressure fluctuations with periods as short as a few seconds is demonstrated. The first observations of ocean-generated atmospheric infrasound with periods of about 5 s and sub-microbar amplitudes, called microbaroms, using single absolute barometers are presented. These barometers can measure microbaroms with amplitudes down to 50 nanobars and the 1-h estimates of microbarom amplitudes calculated from data collected independently with three collocated barometers differed by only a few nanobars. The observed microbaroms have amplitudes between 0.2 microbars and 1 microbar with periods between 3 s and 8 s. The relative accuracy between the barometers is of the order of a few pascals. It is concluded that these absolute quartz-crystal barometers can be used effectively for infrasound monitoring.Electrical engineeringMicrobaromsAbsolute barometersUpper atmosphere windsNanobar precisionDiscrete-time bandpass filterAtmospheric SciencesElectrical and ElectronicsMeteorologyOceanographySignal ProcessingAtmosphereThesis (Open Access)