Press Releases

May 11, 2007
The Japan Agency for Marine-Earth Science and Technology

Drift of TRITON Buoy No.4

TRITON Buoy(Fig.1.2) No.4 belongs to the Japan Agency for Marine-Earth Science and Technology (JAMSTEC; Yasuhiro Kato, President) has been confirmed drifting away from its mooring spot today.

1. Current condition

At 14:43, May 11 (Japan Time), the buoy is drifting eastward at a speed of 1.3km/h from deployed spot of 156E on the equator. With its satellite communication device, we are continuing to determine the buoy’s location.

2. Possible cause

Last May, it had moved 9km from deployed location because it was pulled by a ship or vessel, it did not drift away at that time. We consider that the same way happened in the current case, it was pulled by force of a ship or vessel and the mooring rope (nylon) was cut off (Fig.1)and it drifted this time.

3. Future plan

Location of the drifting buoy has been determined and we are continuing to observe it. And we have asked the Japan Coast Guard to warn ships and vessels around about it. Recovering method and time are now under consideration.

TRITON Buoy is the oceanographic observation buoy deployed mainly around the equator by JAMSTEC.
It observes sea water temperature, salt density up to 750m depth at regular intervals. It also observes wind, atmospheric temperature, humidity, precipitation, insolation and current. Observed data is provided through satellite; and contribute to the study of El Nino and Dipole Phenomenon, and the accuracy of climate prediction such as typhoon onset.


Mr. Ishihara or Mr. Yamaguchi
Long-term Observation Group, Department of Applied Ocean Engineering
Marine Technology Center (MARITEC)
Mr. Shinji Oshima, email;
Manager, Planning Department, Press Office