Offshore Tsunami Current Meters Using Navigation Records (AIS) from Multiple Unspecified Ships
Abstract
We investigated ship navigation records known as Automatic Identification System (AIS) data near the source region of the 2011 Tohoku, Japan tsunami. AIS data of 16 ships in the offshore navigation could be compiled during about 40 minutes after the tsunami generation. Most of the AIS data showed notable deviation of the ship heading from the course over the ground during the tsunami passage. Using the deviation we calculated ship velocity components in the direction normal to the ship heading and found that these velocity components showed good agreement with simulated tsunami currents in the heading-normal direction. The heading-normal velocity components are contaminated by spike-like changes possibly related to abrupt steering of the ship. Once they are removed using the observed yaw angular velocity of the ship, the corrected ship velocity components agreed better with the simulated tsunami currents. The results indicate that the AIS data will work as offshore tsunami current meters from crowdsourced agents.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMNH31D0865I
- Keywords:
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- 4313 Extreme events;
- NATURAL HAZARDS;
- 4315 Monitoring;
- forecasting;
- prediction;
- NATURAL HAZARDS;
- 7212 Earthquake ground motions and engineering seismology;
- SEISMOLOGY;
- 7223 Earthquake interaction;
- forecasting;
- and prediction;
- SEISMOLOGY