It has been 11 years since the Senkaku Islands in Okinawa Prefecture were nationalized.
In the surrounding waters, Chinese coast guard vessels are regularly navigating.

NHK analyzed the movements of Coast Guard ships using data transmitted by the AIS = Automatic Identification System onboard the ship and found that activities in the waters north of the Senkaku Islands have increased significantly in recent years.

(Social Affairs Department reporter: Tatsuya Yamashita)

"Northern Deployment Ship" operating north of the Senkaku Islands

In the waters around the Senkaku Islands, last year Chinese coast guard vessels sailed through the contiguous zone just outside territorial waters for a record number of days.

In addition, interviews with officials revealed that the number of confirmed activities of coast guard vessels has increased significantly in the past few years in the waters just north of the contiguous zone.

Until a few years ago, there were days when activity was not confirmed, but recently it has increased, and this year it was confirmed that four ships were sailing at the same time.

These are separate from ships that sail in the contiguous zone, and although they work as close as they are to the north, they do not enter the contiguous zone, so the Japan Coast Guard calls them "northern deployment ships" and analyzes the purpose of navigation and deploys as many ships as possible to respond to them and continues to be vigilant.

According to multiple sources, the "Northern Deployment Vessels" appear to be increasing their activities near the Senkaku Islands by managing Chinese fishing boats passing through the area, as well as to back up vessels sailing in the contiguous zone.

Masahiro Ichijo, who served as the head of the 11th Regional Coast Guard Headquarters in charge of security for the Senkaku Islands until March, points out that vigilance is necessary.

"I think it is an activity with some intention, but I think it is necessary for the Japan Coast Guard not to be misled and continue to respond calmly.

What is happening north of the Senkaku Islands?

NHK analyzed the movements of ships of the China Coast Guard using data transmitted by AIS = Automatic Identification System onboard ships.

AIS is a device that automatically transmits position and speed information via radio waves to prevent collisions, etc., and is usually not operated by Japan Coast Guard ships because it interferes with security operations.

Until now, the vessels of the China Coast Guard have hardly been activated when entering the EEZ = exclusive economic zone of the Japan, but since March, it has been confirmed that they will be activated around the Senkaku Islands and transmit location information, etc., and it is believed that the aim is to appeal their presence in the surrounding waters.

This time, using AIS data, we confirmed the Chinese coast guard vessels sailing just north and northwest of the contiguous zone around the Senkaku Islands in August.

※Click to play the video.

In the analysis, the location information transmitted by 10 ships of the Coast Guard passing in the vicinity for one month in August was plotted on a map.

Light blue is a ship that has entered territorial waters and contiguous zones that the Japan Coast Guard usually announces, and the color is dark, indicating that navigation in the contiguous zone has become normal.

In addition, you can see that there are also a large number of plots such as orange on the north and northwest sides of the contiguous zone.

This is seen as a new move by the Chinese Coast Guard, which is called the "Northern Deployment Ship." The five ships that were moving in this way were colored orange, red, yellow, brown and pink.

The five ships consistently did not enter the contiguous zone and can be seen moving differently from the light blue ships.

Focusing on the orange color, it entered the northwest side of the contiguous zone around the 8th and sailed for a while, and then entered the northern waters around the 1th, going back and forth quite frequently, occasionally sailing along the line of the contiguous zone.

China Coast Guard ship "Coast Guard 2101" moves in July

In addition, red ships were observed to frequently move back and forth in the waters north of the contiguous zone in July.

The activities of the China Coast Guard becoming the norm

In the waters around the Senkaku Islands, Chinese coast guard vessels are spotted almost every day.

According to the Japan Coast Guard, the number of days in which Coast Guard ships were confirmed in the contiguous zone was 2012 days in 91, when it was nationalized, but the number increased significantly to 2013 days in 232.

After that, it temporarily decreased, but in 2019 it was 282 days, in 2020 it was 333 days, and last year it was 336 days, the highest ever.

In addition, the amount of time spent staying in territorial waters has increased, from 1 hours and 12 minutes in December last year to March and April to match the movement of Japan fishing boats, reaching 72 hours and 45 minutes, the longest time since nationalization.

What is the actual situation at the scene where you face the Coast Guard?

We asked Mr. Ichijo, former chief of the 11th Regional Coast Guard Headquarters, about the actual situation at the site.

"When I was serving as general manager, I felt that there was no sudden escalation, but over a long span of about 10 years, I feel that it is gradually and gradually escalating. Since the Coast Guard is not a place to solve diplomatic problems, I used the term "keep a draw" when I was active so that new diplomatic problems should not arise and unforeseen circumstances would not occur. It's about maintaining the status quo."

When he was on active duty, Mr. Ichijo was often asked if the Japan Coast Guard was okay even though the threat was increasing, and each time he explained that there was advanced equipment and a coast guard who could make full use of that equipment, and then told him, "It's okay, so don't worry."
Mr. Ichijo also pointed out that it is important to face the other person calmly and calmly.

The point is not to create an opportunity for something to escalate or something to happen accidentally, and I think it is important to be mentally prepared for when something unexpected happens."