Global observations of ocean-bottom subinertial current dissipation

Abstract

Quadratic bottom boundary layer drag is a potentially significant source of energy dissipation in the deep ocean. This study presents a new estimate of the energy dissipated by this process, using results from the world's largest archive of ocean current meter time series and focusing strongly upon the potential uncertainties in this calculation. Two methods are used, one based on a simple division of the World Ocean into a series of regular grids and the other based on a more sophisticated analysis using a hierarchical clustering mechanism assisted by estimates from the Hybrid Coordinate Ocean Model (HYCOM) model. From these analyses, the authors estimate a globally integrated bottom boundary layer dissipation of 0.65 ± 0.15 (statistical uncertainty) ± 0.15 (methodological uncertainty) TW. © 2013 American Meteorological Society.