1) Reconstructions of ice-berg rafted debris from the Antarctic coast reveal greater variability in Antarctic Ice Sheet discharge during the Holocene than previously assumed, particularly on multi-centennial timescales. 2) Ice sheet modeling shows that small subsurface ocean temperature changes, coupled with ice sheet dynamics, can produce substantial variations in ice discharge at multi-centennial frequencies. 3) Climate model simulations indicate that Antarctic Ice Sheet discharge variations induced changes in Southern Ocean temperatures and deep water formation that affected climate variability on multi-centennial timescales globally through atmospheric teleconnections.