Paroscientific Poster Presentation EarthScope 2007 National Meeting - PowerPoint PPT Presentation

Paroscientific Poster Presentation EarthScope 2007 National Meeting Paroscientific, Inc. Tel: (425) 883-8700 4500 148th Ave. N.E. Fax: (425) 867-5407 Redmond, WA 98052 E-Mail:support@paroscientific.com http://www.paroscientific.com

Mitigating Seismic Noise Caused by Atmospheric Pressure Changes With Collocated, High-resolution, Broadband Barometers Local atmospheric pressure fluctuations are significant sources of noise in seismic data. Pressure changes associated with common atmospheric phenomena such as frontal passages, jet-stream passages, boundary-layer convection, and gravity waves can deform the ground that surrounds a seismometer to cause significant horizontal tilt noise. Other atmospheric influences include the gravitational effects of a variable weight of the column of air above the seismometer, vertical ground deformations, and possible buoyancy effects. The reconstruction and elimination, in real time or post facto , of these atmospheric effects requires the monitoring of local pressure changes with collocated high-resolution, broadband barometers. The pressure-induced noise can be deterministically removed from the seismometer, strainmeter, and tiltmeter data to substantially increase the overall performance of an entire sensor network such as EARTHSCOPE. High-resolution barometers can also improve the analysis of the Earth’s free oscillations by measuring and correcting for atmospheric effects. The enhanced instrumentation can also provide multi-use, cross-disciplinary benefits for the atmospheric sciences community including Infrasound Studies, GPS-Meteorology, Airport Applications, and Hazardous Material Detection. We present and describe a state-of-the-art, high-resolution, broadband barometer and wind-insensitive pressure port that are well suited for the mitigation of seismic noise caused by pressure changes as well as atmospheric applications. Table of Contents Chart Number Mitigation of Pressure-induced Seismic Noise 1 Summary from W. Zurn and E. Wielandt, “On the minimum of vertical seismic noise near 3 mHz” 2 Abstract from Holger Steffen, “The importance of instrument location on barometric pressure-induced noise” and Abstract from H. Steffen, S. Kuhlmannb, T. Jahrc, & C. Kronerc, “Numerical modelling of the barometric pressure-induced noise in horizontal components for the observatories Moxa and Schiltach” Free Oscillations of the Earth 3 Summary from K. Nishida, Y. Fukao, S. Watada, N. Kobayashi, M. Tahira, N. Suda & K. Nawa, “ Array observation of background atmospheric waves in the seismic band from 1 mHz to 0.5 Hz” Atmospheric Applications for Broadband Barometers 4 Abstract from Eric Calais & J. Bernard Minster, “GPS, earthquakes, the ionosphere, and the Space Shuttle” 5 Hazardous Material Detection & Airport Applications 6 GPS Meteorology & Infrasonic Applications Resonant Quartz Sensor 7 Construction & Operation 8 Barometer Performance 9 High Performance Pressure Port Quartz Strong Motion Sensor 10 QSMS Design and Performance AtmoScope 11 Interdisciplinary Research Using Broadband Barometers Collocated with EarthScope Seismometers