Japan spots Chinese sea research vessel

A Chinese oceanic research vessel was spotted by the Japan Coast Guard in Japan's claimed exclusive economic zone (EEZ) while Chinese authorities confirmed Monday that they have not received any warning and research continues in the area.

"The mission is for ordinary scientific purposes, nothing special. The institute has not received any response or protest from Japan and the vessel is still conducting its mission in the West Pacific Ocean according to its schedule," an official from the Institute of Oceanology under the Chinese Academy of Sciences told the Global Times on Monday.

The official said that it was the first scientific research mission in the West Pacific Ocean carried out by the vessel Kexue, China's most sophisticated research vessel, since April 8. Its research will focus on Pacific currents, regional climate and deep-sea ecology in the Okinawa Trough area.

The official's comments came after Japanese Kyodo News reported its coast guard headquarters in Okinawa said Kexueappeared in its EEZ off Kume Island on Saturday and Sunday.

An officer from the 11th district of Japanese Coast Guard in Naha told the Global Times that a Japanese jet discovered the Chinese vessel at 4:21 pm Saturday afternoon. The Japanese side immediately sent out warning signals in three languages, Japanese, English and Chinese, to the Chinese vessel and demanded it stop all investigation activities.

When the vessel failed to oblige, the Japanese side did not take further action, the Japanese official said.

The Japanese Coast Guard said that Kexuedropped what appeared to be a wire into the sea and the Japanese authorities will not accept any research in its EEZ without approved notification, according to Japanese Jiji Press on Saturday.

Japan's EEZ has caused tensions between Japan and China in the East China Sea, due to over 100,000 square kilometers of disputed waters, including the Diaoyu Islands.

Hu Lingyuan, a Japanese Studies professor from Fudan University, told the Global Times on Monday that the Okinawa Trough lies in the heart of the demarcation of the continental shelf in the East China Sea.

"China believes that the Okinawa Trough serves as the boundary between the continental shelves of China and Japan and the geophysical factors should be taken into consideration legally in the demarcation between the two countries," said Hu.

In August 2013, China did a presentation to the Commission on the Limits of the Continental Shelf under UN Convention on the Law of the Sea (UNCLOS). The presentation provided scientific evidence that China's continental shelf in the East China Sea naturally extends to the Okinawa Trough, which was over 200 nautical miles away from the mainland baseline.

"As the coasts between the two countries are less than 400 nautical miles, Japan unilaterally uses the median line to divide the two states but according to UNCLOS, the waters near the Okinawa Trough do not belong to Japan as the trough constitutes a fundamental discontinuity between the natural prolongation of China and Japan," Hu said.