Numerical simulations of debris drift from the Great Japan Tsunami of 2011 and their verification with observational reports

MARINE POLLUTION BULLETIN

卷:132

Article

Maximenko, Nikolai¹  Hafner, Jan¹  Kamachi, Masafumi²  MacFadyen, Amy³ 

[1] Univ Hawaii Manoa, Sch Ocean & Earth Sci & Technol, Int Pacific Res Ctr, Honolulu, HI 96822 USA

[2] Japan Agcy Marine Earth Sci & Technol, Yokosuka, Kanagawa, Japan

[3] US Natl Ocean & Atmospher Adm, Off Response & Restorat, Emergency Response Div, Silver Spring, MD USA

关键词: Numerical modeling;    Data analysis;    Ocean surface circulation;    Marine debris drift;    Tsunami debris;    Debris pathways;    Sensitivity to windage;    Debris reports;    Model calibration/validation;    Model-data comparison;    New methods;   

DOI  :  10.1016/j.marpolbul.2018.03.056

来源: Elsevier

【 摘 要 】

A suite of five ocean models is used to simulate the movement of floating debris generated by the Great Japan Tsunami of 2011. This debris was subject to differential wind and wave-induced motion relative to the ambient current (often termed windage) which is a function of the shape, size, and buoyancy of the individual debris items. Model solutions suggest that during the eastward drift across the North Pacific the debris became stratified by the wind so that objects with different windages took different paths: high windage items reached North America in large numbers the first year, medium windage items recirculated southwest toward Hawaii and Asia, and low windage items collected in the Subtropical Gyre, primarily in the so-called garbage patch area located northeast of Hawaii and known for high concentrations of microplastics. Numerous boats lost during the tsunami were later observed at sea and/or found on the west coast of North America: these observations are used to determine optimal windage values for scaling the model solutions. The initial number of boats set adrift during the tsunami is estimated at about 1000, while about 100 boats are projected to still float in year 2018 with an e-folding decay of 2 to 8 years.

【 授权许可】

Free