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. (Xinhua/Huang Taoming)