China has completed a large scale installation of submerged buoys in the west Pacific ocean for the first time, a move essential to continuous observation of the ocean environment.

China's most sophisticated research vessel Kexue, or Science, returned to the eastern port city of Qingdao on Tuesday after wrapping up an 82-day ocean expedition, during which it put 17 sets of submerged buoys in the key marine areas of the west Pacific and retrieved three, according to the Institute of Oceanology, under the Chinese Academy of Sciences (CAS).

It marks the first time that China has put an array of submerged buoys on such a big scale, said Hu Dunxin, a CAS academician.

"The buoys will provide important scientific statistics about ocean circulation and climate," Hu said, adding that the research will help scientists better understand the relation between warm ocean in the Western Pacific and climate change.

The expedition will also improve knowledge about the water and climate conditions of the west Pacific, said Yu Fei, chief scientist of the trip.

Kexue is expected to return to the marine area in mid-November to conduct a deep sea environment project by the CAS.

Weighing 4,711 tonnes, Kexue is 99.8 meters long and 17.8 meters wide. With a cruising capacity of 15,000 nautical miles and a top speed of 15 knots, it can travel with a crew of 80 for 60 days.