China's sixth Arctic expedition has found the region's sea ice continuing to shrink at an alarming rate.

The ice shrank to an annual low on Sept 15, when its 5.07 million square km was the sixth-smallest coverage since records began in 1979, said Lei Ruibo, a crew member on board Xuelong, which is due to return to Shanghai on Wednesday after 76 days at sea.

"Though the Arctic sea ice area has been comparatively large in the past eight years, it's still far below the average 6.14 million square km since 1979," said Lei. "So we believe the Arctic sea ice is still receding."

One of the key roles of this expedition has been researching how the atmosphere, current and ice of the Arctic interact.

The dramatic receding of the ice has largely affected the Northern Hemisphere in recent years, causing disastrous freezing rain in south China during the 2007-2008 winter, for example.

Xuelong set off from its Shanghai base on July 11 and was expected to travel over 11,000 nautical miles during its voyage.

The expedition team has explored key areas such as the Bering Sea, the Chukchi Sea and the Canada Basin.