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Understanding deformation in ice shelves is necessary to evaluate the response of ice shelves to thinning. We study microseismicity associated with ice shelf deformation using nine broadband seismographs deployed near a rift on the Ross Ice Shelf. From December 2014 to November 2016, we detect 5,948 icequakes generated by rift deformation. Locations were determined for 2,515 events using a least squares grid‐search and double‐difference algorithms. Ocean swell, infragravity waves, and a significant tsunami arrival do not affect seismicity. Instead, seismicity correlates with tidal phase on diurnal time scales and inversely correlates with air temperature on multiday and seasonal time scales. Spatial variability in tidal elevation tilts the ice shelf, and seismicity is concentrated while the shelf slopes downward toward the ice front. During especially cold periods, thermal stress and embrittlement enhance fracture along the rift. We propose that thermal stress and tidally driven gravitational stress produce rift seismicity with peak activity in the winter. Plain Language Summary: In Antarctica, large bodies of floating ice called ice shelves help prevent ice on land from sliding into the ocean. To predict how Antarctica might respond to climate change, we need to understand how ice shelves interact with the environment, including the atmosphere and the ocean. The largest ice shelf, the Ross Ice Shelf, is over 500,000 km2 in area, making it the largest body of floating ice in the world. In this study, we deployed nine seismographs, the same instruments used to study earthquakes, to monitor vibrations and cracking within the Ross Ice Shelf over a 2‐year period. During that time, the instruments detected nearly 6,000 fracture events along a 120‐km‐long crack in the ice shelf. We compared the timing of the cracking to air temperature data, ocean wave activity, and tides to see whether these factors influenced the crack's behavior. We found that fracture occurs most frequently just after high tide during winter and when the air is very cold. We also found that fracture at the rift is not triggered by ocean waves. This work demonstrates that Antarctic ice shelves are very sensitive to the environment and highlights the need to continue studying them. Key Points: 2,515 icequakes associated with rift deformation on the Ross Ice Shelf are located using a double‐difference location algorithmIcequake timing correlates with tidal phase diurnally and inversely correlates with air temperature on multiday and seasonal time scalesOcean swell, infragravity waves, and a significant tsunami arrival are not correlated with increased rift activity [ABSTRACT FROM AUTHOR]

Focuses on the developments in digital stations of the Global Seismograph Network located in Antarctica, as of December 1995. Efforts of the stations in recording seismic data for over 30 years; Information on a training undergone by technicians in system maintenance and seismogram interpretation; Plan for the relocation of the South Pole seismic station several kilometers from the present habitation.