Replacement of the seismic monitoring system at Syowa Station, corresponding to the INTERSAT link

The seismic observation system at Syowa Station, Antarctica, was partially improved in association with introduction of the INTERSAT communication link from February 2004.  The workstation used for acquisition of the seismic signals was replaced by a new one (geotail; IP:133.57.32.60) at the Earth Science Laboratory (ESL). Digital waveform data have been automatically transmitted from a 24-bit A/D converter (Q680; IP:133.57.32.67) to the workstation on TCP/IP protocol by using `Comserv' software. Among several kinds of seismic signals, 20 Hz continuous data of both short-period (HES) and broadband (STS-1) seismometers have been automatically transferred once a day to the National Institute of Polar Research (NIPR) by using the Unix-to-Unix-Copy (UUCP) protocol via the INTERSAT link. Besides remote operations and monitoring data from NIPR to the acquisition system at ESL, Internet access to the observation system at Syowa Station has significantly improved. For instance, network cameras were introduced both in ESL and the Seismological Hut, which provide real-time images for monitoring related instruments, analogue recorders and room temperature measurements, even when nobody can approach the ESL or Hut during severe weather.  The above improvements involving the INTERSAT link have brought several advantages not only to the data transport/communication processes but also to reduce daily maintenance efforts at the Station.  In this report, several topics are demonstrated concerning improvements of seismic monitoring observations associated with the INTERSAT link, followed by introduction of the data archive and publication via the Internet