HR: 1340h
AN: SM13A-0312    [Abstracts]
TI: Automated Detection of Pi2 Pulsations by Wavelet Analysis and its Application to Real-time Data From Longitudinal Network of Geomagnetic Observatories
AU: * Nosé, M
EM: nose@kugi.kyoto-u.ac.jp
AF: Data Analysis Center for Geomagnetism and Space Magnetism, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto, 606-8502 Japan
AU: Iyemori, T
SM13A-0312 AF: Data Analysis Center for Geomagnetism and Space Magnetism, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto, 606-8502 Japan
AU: Takeda, M
SM13A-0312 AF: Data Analysis Center for Geomagnetism and Space Magnetism, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto, 606-8502 Japan
AU: Kamei, T
SM13A-0312 AF: Data Analysis Center for Geomagnetism and Space Magnetism, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto, 606-8502 Japan
AU: Honary, F
SM13A-0312 AF: Department of Communications Systems, Lancaster University, South Drive, Lancaster, LA1 4WA United Kingdom
AU: Marple, S
SM13A-0312 AF: Department of Communications Systems, Lancaster University, South Drive, Lancaster, LA1 4WA United Kingdom
AU: Matzka, J
SM13A-0312 AF: Department of Earth and Environmental Sciences, Ludwig-Maximilians University, Ludwigshoehe 8, Fuerstenfeldbruck, 82256 Germany
AU: Ookawa, T
SM13A-0312 AF: Kakioka Magnetic Observatory, 595 Kakioka, Yasato-machi, Niihara-gun, Ibaraki, 315-0116 Japan
AU: Takahashi, K
SM13A-0312 AF: Applied Physics Laboratory, Johns Hopkins University, 11100 Johns Hopkins Road, Laurel, MD 20723-6099 United States
AU: Toth, B
SM13A-0312 AF: Applied Physics Laboratory, Johns Hopkins University, 11100 Johns Hopkins Road, Laurel, MD 20723-6099 United States
AU: Nava, G C
SM13A-0312 AF: UNAM. Instituto de Geofisica, Ciudad Universitaria, Coyoacan, Mexico, D. F., 04510 Mexico
AB: Pi2 pulsations are defined as geomagnetic field variations with a period range of 40-150 s and an irregular waveform. It is generally accepted that Pi2 pulsations appear clearly in mid- or low-latitude ground station on the nightside in a close connection with substorm onsets. Thus nowcasting of substorm onset becomes possible, if we monitor geomagnetic field variations and detect Pi2 pulsations in real-time. We have developed an algorithm to detect Pi2 pulsations with wavelet analysis, which is suitable for investigating waves that are limited in both time and frequency, such as Pi2 pulsations [ Nosé et al., Earth Planet. Space, p. 773-783, 1998]. Using the geomagnetic field data from the Kakioka observatory, we have tested the algorithm and found that detection results by the algorithm on the nightside are fairly consistent with the detection results by visual inspection. Based on this successful test result the algorithm has been applied to real-time geomagnetic field data obtained at the Mineyama and Kakioka observatories in Japan, as well as the York SAMNET station in the U. K. since 1996. We started the Pi2 detection at Fürstenfeldbruck in Germany in July 2005. Detection results are exchanged among these stations via the Internet and are available at our WWW site. We are planning to use the same algorithm to detect Pi2 pulsations at APL (Applied Physics Laboratory) in the United States and Teoloyucan in Mexico. The network of these 6 observatories will result in more reliable detection of Pi2 pulsations, because at least one station is located on the nightside at any given time.
DE: 0520 Data analysis: algorithms and implementation
DE: 2752 MHD waves and instabilities (2149, 6050, 7836)
DE: 2790 Substorms
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005