British swimmer Lewis Gordon Pugh, dubbed the "human polar bear," has completed the first-ever swim under an ice sheet in Antarctica. Jeff Semple explains how Pugh did it to raise awareness of climate change, and the dire threat facing Antarctica. For more info, please go to www.globalnews.ca Subscribe to Global News Channel HERE: bit.ly/20fcXDc Like Global News on Facebook HERE: bit.ly/255GMJQ Follow Global News on Twitter HERE: bit.ly/1Toz8mt Follow Global News on Instagram HERE: bit.ly/2QZaZIB #GlobalNews #Antarctica #ClimateChange