Chinese icebreaker Xuelong (Snow Dragon) sailed for home on Tuesday after completing its fourth scientific expedition in the Arctic Ocean.

Since its arrival in the Arctic Ocean on July 20, the Chinese expedition team has completed a comprehensive oceanographic survey of more than 130 marine stations, short-term and long-term ice stations, breaking many records in the history of China's Arctic expedition and navigation.

The arrival point at 88.22 degrees north latitude and 177.20 degrees west longitude marked the farthest north the researchers had ever been.

With the help of ice observations, ice buoys, airborne remote sensing, and other technology, the team obtained over 8 million groups of data with respect to aerology, oceanography, hydrology and ecology.

Numerous water samples, biological samples and 192 samples from the ice core with a length of 300 meters were also collected during the expedition.

On Aug. 20, a group of Chinese scientists reached the North Pole, extending their research in the Arctic Ocean to the earth's northernmost point.

The scientists carried out a series of research activities at the Pole, including collecting sea ice and seawater samples and ecological observation.