Inertia‐induced accumulation of flotsam in the subtropical gyres
Abstract
Recent surveys of marine plastic debris density have revealed high levels in the center of the subtropical gyres. Earlier studies have argued that the formation of great garbage patches is due to Ekman convergence in such regions. In this work we report a tendency so far overlooked of drogued and undrogued drifters to accumulate distinctly over the subtropical gyres, with undrogued drifters accumulating in the same areas where plastic debris accumulate. We show that the observed accumulation is too fast for Ekman convergence to explain it. We demonstrate that the accumulation is controlled by finite‐size and buoyancy (i.e., inertial) effects on undrogued drifter motion subjected to ocean current and wind drags. We infer that the motion of flotsam in general is constrained by similar effects. This is done by using a newly proposed Maxey‐Riley equation which models the submerged (surfaced) drifter portion as a sphere of the fractional volume that is submerged (surfaced).
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 15, 2016
- Source ID
- 10.1002/2016gl071443
Entities
People
- Francisco Beron-Vera
- Maria J. Olascoaga
- Rick Lumpkin
Organizations
- Gulf of Mexico Research Initiative
- National Oceanic and Atmospheric Administration
- United States Navy
- University of Miami