The GreenLand Ice Sheet Monitoring Network (GLISN): Japanese-American Cooperative Field Operations and Preliminary Data Analyses

Melting of the Greenland ice sheet is now in progress accompanying the global climate change. Recently, a new type of seismic event called "glacial earthquakes", which are generated by the movement of a large mass of ice within the glacial terminus, has been realized as a new way to monitor current ice sheet dynamics. In 2009, the multinational GreenLand Ice Sheet monitoring Network (GLISN), a large broadband seismological network in and around Greenland was initiated to monitor these events. Japan, a partner country of the GLISN project has been sending a field team each year since 2011. The joint U.S. and Japanese team first constructed a dual seismic/GPS station (station code: ICESG-GLS2) on the Greenland ice sheet. In 2012 and 2013 same team contributed to the maintenance of ICESG as well as DY2G-GLS1 and NUUK. This presentation summarizes our field activities on the GLISN project for three years, and shows accuracy of long-period seismic waveform data from the above stations. Data quality has been checked by comparing the observations with global synthetic seismograms. The result indicates that the data from the three stations does not contain fluctuation related to the installation status, and the quality is consistent. We intend to continue our activities in order to obtain the highest quality data as is possible from the GLISN seismograph network. Our activity is supported by JSPS KAKENHI 24403006.