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Title: Inertia Influences Pelagic Sargassum Advection and Distribution
Abstract

The effect of inertia (resistance to a change in velocity of buoyant finite‐sized objects) on the advection of pelagicSargassum, a macroalgae, is a function of the size and density of naturalSargassumrafts. Here we present observations ofSargassumdensity and an approach for estimating an effective radius ofSargassumrafts from remote‐sensing observations. This allows the existing theoretical framework for Lagrangian modeling of inertial effects on spherical particles to be applied toSargassum. Accounting for inertia yields up to a 20% increase inSargassumexport from the Sargasso Sea southward and provides a return pathway to the tropics that may be important to maintaining a self‐sustaining population. Resolving inertial effects also leads to increases in retention in the Gulf of Mexico and Caribbean Sea, whereSargassuminundation events are increasingly common. Including inertial effects in models ofSargassumadvection could improve predictions of these events.

 
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PAR ID:
10460679
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
46
Issue:
5
ISSN:
0094-8276
Page Range / eLocation ID:
p. 2610-2618
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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