Chief engineer Li Wenming (4th L) speaks after a power loss drill aboard China's research icebreaker Xuelong 2. Currently on China's 41st Antarctic expedition, research icebreakers Xuelong and Xuelong 2, or Snow Dragon and Snow Dragon 2, will begin to plough through the belt of prevailing westerlies, nicknamed the "rolling forties," on Tuesday. (Photo: Xinhua)

First mate Zhu Pengtao (L) and sailor Chen Dongbin adjust the navigation course aboard China's research icebreaker Xuelong 2. Currently on China's 41st Antarctic expedition, research icebreakers Xuelong and Xuelong 2, or Snow Dragon and Snow Dragon 2, will begin to plough through the belt of prevailing westerlies, nicknamed the "rolling forties," on Tuesday. (Photo: Xinhua)

An aerial drone photo shows China's research icebreaker Xuelong 2 sailing in the sea. Currently on China's 41st Antarctic expedition, research icebreakers Xuelong and Xuelong 2, or Snow Dragon and Snow Dragon 2, will begin to plough through the belt of prevailing westerlies, nicknamed the "rolling forties," on Tuesday. (Photo: Xinhua)

Meteorologist Liu Sufang (L) studies weather conditions and plans navigation route aboard China's research icebreakers Xuelong 2. Currently on China's 41st Antarctic expedition, research icebreakers Xuelong and Xuelong 2, or Snow Dragon and Snow Dragon 2, will begin to plough through the belt of prevailing westerlies, nicknamed the "rolling forties," on Tuesday. (Photo: Xinhua)

Helicopter crew member Bi Lingfeng works aboard China's research icebreaker Xuelong 2. Currently on China's 41st Antarctic expedition, research icebreakers Xuelong and Xuelong 2, or Snow Dragon and Snow Dragon 2, will begin to plough through the belt of prevailing westerlies, nicknamed the "rolling forties," on Tuesday. (Photo: Xinhua)