Observed Gravity Change at Syowa Station Induced by Antarctic Ice Sheet Mass Change

Continuous observations with superconducting gravimeters (SG) TT-70 #016 and CT#043 have been on-going since 1993 to monitor Earth tides and Earth’s free oscillations at a gravity observation hut in Syowa Station, Antarctica. We obtained gravity residuals from the SG CT#043 data by subtracting Earth tides, effects of atmospheric pressure changes and polar motion, and instrumental drift from the original record. The smoothed gravity residuals obtained by taking a running mean of 33 days reveal variations from –5 to +5 μgal (10–8m/s2).