Photo taken on Feb. 1, 2020 shows icebergs seen from China's polar icebreaker Xuelong 2, or Snow Dragon 2, which is heading to China's Zhongshan Station during China's 36th Antarctic expedition, on the Weddell Sea. (Photos: Xinhua)

Photo taken on Feb. 2, 2020 shows a whale seen from China's polar icebreaker Xuelong 2, or Snow Dragon 2, which is heading to China's Zhongshan Station during China's 36th Antarctic expedition, on the Weddell Sea.

Photo taken on Feb. 1, 2020 shows icebergs seen from China's polar icebreaker Xuelong 2, or Snow Dragon 2, which is heading to China's Zhongshan Station during China's 36th Antarctic expedition, on the Weddell Sea.

Photo taken on Feb. 1, 2020 shows a whale seen from China's polar icebreaker Xuelong 2, or Snow Dragon 2, which is heading to China's Zhongshan Station during China's 36th Antarctic expedition, on the Weddell Sea.

Photo taken on Feb. 5, 2020 shows an iceberg seen from China's polar icebreaker Xuelong 2, or Snow Dragon 2, which is heading to China's Zhongshan Station during China's 36th Antarctic expedition, on the Weddell Sea.

Photo taken on Feb. 1, 2020 shows an iceberg seen from China's polar icebreaker Xuelong 2, or Snow Dragon 2, which is heading to China's Zhongshan Station during China's 36th Antarctic expedition, on the Weddell Sea.

Photo taken on Feb. 2, 2020 shows a whale seen from China's polar icebreaker Xuelong 2, or Snow Dragon 2, which is heading to China's Zhongshan Station during China's 36th Antarctic expedition, on the Weddell Sea.