The Antarctic Ice Sheet has lost mass between 1992 and 2017 (very high confidence), with an increasing mass-loss rate over this period (medium confidence).At sustained warming levels between 1.5°C and 2°C, the ice sheets will continue to lose mass (high confidence); on time scales of multiple centuries, the Greenland and West Antarctic ice sheets will partially be lost (medium confidence); there is limited evidence that the Greenland and West Antarctic ice sheets will be lost almost completely and irreversibly over multiple millennia; at sustained warming levels between 2°C and 3°C, there is limited evidence that the Greenland and West Antarctic ice sheets will be lost almost completely and irreversibly over multiple millennia, and high confidence in increasing risk of complete loss and increasing rate of mass loss for higher warming; At sustained warming levels between 3°C and 5°C, near- complete loss of the Greenland Ice Sheet and complete loss of the West Antarctic Ice Sheet will occur irreversibly over multiple millennia (medium confidence); substantial parts or all of Wilkes Subglacial Basin in East Antarctica will be lost over multiple millennia