Staff members check a helicopter on China's research icebreaker Xuelong, also known as the Snow Dragon, on Nov. 21, 2018. (Photos: Xinhua)

Staff members reinforce the chain on China's research icebreaker Xuelong, also known as the Snow Dragon, on Nov. 21, 2018.

Staff members check a helicopter on China's research icebreaker Xuelong, also known as the Snow Dragon, on Nov. 21, 2018.

China's research icebreaker Xuelong, also known as the Snow Dragon, sails across westerlies on Nov. 20, 2018. The icebreaker is on China's 35th Antarctic research expedition. At 6:22 p.m. Wednesday (local time), Xuelong crossed the stormy westerlies on its way toward China's Zhongshan Station in Antarctic.

Captain of China's research icebreaker Xuelong and meteorological forecasters work on the ship on Nov. 21, 2018. At 6:22 p.m. Wednesday (local time), Xuelong crossed the stormy westerlies on its way toward China's Zhongshan Station in Antarctic.