11:45 AM - 12:00 PM
[SSS05-11] 15 years of the GLISN seismic network in Greenland (1): Observations
Keywords:Greenland, Seismic observation, Ice sheet
Over 80% of Greenland’s surface is covered by the Greenland Ice Sheet (GrIS). In recent years, melting of the GrIS has been a concern, and seismic observations to monitor the melting process have gained attention. However, due to the difficulty of observations in the interior, by 2008, there were only 16 seismic stations, including those on surrounding islands, with just one on the GrIS. Such a situation highlighted the need to expand and reinforce the observation network.
An international project called the Greenland Ice Sheet Monitoring Network (GLISN) was launched in 2009 (Clinton et al., 2014). With the cooperation of 11 countries (Denmark, Canada, Germany, Italy, Japan, Norway, Switzerland, USA, France, Korea, and Poland), efforts had been made to increase the number of stations, and currently, a total of 34 stations are in operation.
A major characteristic of GLISN is the installation of three new stations on the GrIS: DY2G, ICESG, and NEEM (Toyokuni et al., 2014). The installation and maintenance of these stations have been carried out by a joint USA–Japan observation team. The team was dispatched annually from 2011 to 2018 and was involved in maintaining not only the three stations on the GrIS but also three stations on outcrops. At all three newly installed stations on the GrIS, broadband seismometers (Güralp CMG-3T) designed for cold temperatures were equipped, recording three-component seismograms at a sampling rate of 100 Hz. At the DY2G and NEEM stations, borehole seismometers (Güralp CMG-3TB) were also installed at a depth of ~300 m using the vertical shaft of the ice core drilling. Additionally, GPS stations were installed near the seismometers to monitor ice flow and snow accumulation.
Another characteristic of GLISN is the immediate release of data. By using satellite communication, transfer of seismic waveform data (20 sps) from the GrIS was successfully achieved in 2014, which was the first transfer of broadband seismogram from ice sheet. This made it possible to download data from all GLISN observation points in near real-time.
Since 2019, due to budget cuts from the U.S. National Science Foundation and the COVID-19 pandemic, observations on the GrIS have been halted. However, the accumulated data is being actively analyzed. The results will be presented as "15 years of the GLISN seismic network in Greenland (2): Achievements" in the M-TT36 session.
References
Clinton, J. F., Nettles, M., Walter, F., Anderson, K., Dahl-Jensen, T., Giardini, D., Govoni, A., Hanka, W., Lasocki, S., Lee, W. S., McCormack, D., Mykkeltveit, S., Stutzmann, E., Tsuboi, S. (2014) Eos, Trans. AGU, 95(2), 13–14.
Toyokuni, G., Kanao, M., Tono, Y., Himeno, T., Tsuboi, S., Childs, D., Anderson, K., Takenaka, H. (2014) Antarct. Rec., 58(1), 1–18.
An international project called the Greenland Ice Sheet Monitoring Network (GLISN) was launched in 2009 (Clinton et al., 2014). With the cooperation of 11 countries (Denmark, Canada, Germany, Italy, Japan, Norway, Switzerland, USA, France, Korea, and Poland), efforts had been made to increase the number of stations, and currently, a total of 34 stations are in operation.
A major characteristic of GLISN is the installation of three new stations on the GrIS: DY2G, ICESG, and NEEM (Toyokuni et al., 2014). The installation and maintenance of these stations have been carried out by a joint USA–Japan observation team. The team was dispatched annually from 2011 to 2018 and was involved in maintaining not only the three stations on the GrIS but also three stations on outcrops. At all three newly installed stations on the GrIS, broadband seismometers (Güralp CMG-3T) designed for cold temperatures were equipped, recording three-component seismograms at a sampling rate of 100 Hz. At the DY2G and NEEM stations, borehole seismometers (Güralp CMG-3TB) were also installed at a depth of ~300 m using the vertical shaft of the ice core drilling. Additionally, GPS stations were installed near the seismometers to monitor ice flow and snow accumulation.
Another characteristic of GLISN is the immediate release of data. By using satellite communication, transfer of seismic waveform data (20 sps) from the GrIS was successfully achieved in 2014, which was the first transfer of broadband seismogram from ice sheet. This made it possible to download data from all GLISN observation points in near real-time.
Since 2019, due to budget cuts from the U.S. National Science Foundation and the COVID-19 pandemic, observations on the GrIS have been halted. However, the accumulated data is being actively analyzed. The results will be presented as "15 years of the GLISN seismic network in Greenland (2): Achievements" in the M-TT36 session.
References
Clinton, J. F., Nettles, M., Walter, F., Anderson, K., Dahl-Jensen, T., Giardini, D., Govoni, A., Hanka, W., Lasocki, S., Lee, W. S., McCormack, D., Mykkeltveit, S., Stutzmann, E., Tsuboi, S. (2014) Eos, Trans. AGU, 95(2), 13–14.
Toyokuni, G., Kanao, M., Tono, Y., Himeno, T., Tsuboi, S., Childs, D., Anderson, K., Takenaka, H. (2014) Antarct. Rec., 58(1), 1–18.