Generation of Near‐Inertial Currents on the Mid‐Atlantic Bight by Hurricane Arthur (2014)

Abstract

Near‐inertial currents (NICs) were observed on the Mid‐Atlantic Bight (MAB) during the passage of Hurricane Arthur (2014). High‐frequency radars showed that the surface currents were weak near the coast but increased in the offshore direction. The NICs were damped out in 3–4 days in the southern MAB but persisted for up to 10 days in the northern MAB. A Slocum glider deployed on the shelf recorded two‐layer baroclinic currents oscillating at the inertial frequency. A numerical model was developed to interpret the observed spatial and temporal variabilities of the NICs and their vertical modal structure. Energy budget analysis showed that most of the differences in the NICs between the shelf and the deep ocean were determined by the spatial variations in wind energy input. In the southern MAB, energy dissipation quickly balanced the wind energy input, causing a rapid damping of the NICs. In the northern MAB, however, the dissipation lagged the wind energy input such that the NICs persisted. The model further showed that mode‐1 waves dominated throughout the MAB shelf and accounted for over 70% of the current variability in the NICs. Rotary spectrum analyses revealed that the NICs were the largest component of the total kinetic energy except in the southern MAB and the inner shelf regions with strong tides. The NICs were also a major contributor to the shear spectrum over an extensive area of the MAB shelf and thus may play an important role in producing turbulent mixing and cooling of the surface mixed layer.

A Numerical Study of Near Inertial Motions in Mid-Atlantic Bight Area Induced by Hurricane Irene (2011)

“…CC BY 4.0 License. Umlauf and Burchard (2003) for detailed description), a widely employed model that demonstrated good performance in simulating various oceanographic processes (Olabarrieta et al, 2011;Toffoli et al, 2012;Zhang et al, 2018).…”

“…Shown in Figure 3a is the vertical profile of the seawater temperature measured by Glider RU16 launched off the New Jersey Coast. Glider RU16 was an autonomous underwater vehicle of the Slocum glider platform developed by Teledyne-Webb Research (Schofield et al, 2007(Schofield et al, , 2010, which has demonstrated to be advantageous in marine monitoring, particularly under extreme weather conditions (Glenn et al, 2016;Miles et al, 2017;Seroka et al, 2016;Zhang et al, 2018). Glider RU16 can measure not only the vertical profiles of seawater temperature and salinity but also the water depth.…”

“…CC BY 4.0 License. Zhang et al, 2018). The decrease of current velocity in shallow waters may be an effect of the sea-bottom friction as Rayson et al (2015) pointed out.…”

“…Shen et al (2017) investigated five TCs over the Taiwan Strait and identified a rapid decaying rate due to nonlinear interaction between NICs and tides. Zhang et al (2018) studied Hurricane Arthur in Mid-Atlantic Bight and showed that excessive wind input does not necessarily lead to amplification of NICs because intensive wind input is usually accompanied by an even higher rate of energy dissipation. Avila and Cangialosi (2011).…”

Impacts of Hurricane Irma on the Circulation and Transport in Florida Bay and the Charlotte Harbor Estuary

“…In open ocean regions, hurricane impacts include the mixing of deeper water properties into the surface layer, direct air-sea exchange of moisture and heat from the sea surface, and the generation of near-inertial currents and surface and internal waves (e.g., Price 1981;Shay et al 1990Shay et al , 1992Sanford et al 2011;D'Asaro et al 2014;Zhang et al 2016). On continental shelves, hurricanes can cause coastal upwelling (or downwelling) (e.g., Smith 1982), rapid shelf-wide cooling (e.g., Zambon et al 2014;Glenn et al 2016;Seroka et al 2017), and near-inertial currents (e.g., Teague et al 2007;Shen et al 2017;Zhang et al 2018). In nearshore and coastal regions, hurricanes can induce strong currents, waves, and storm surges (e.g., Zheng 2006b, 2008;Dietrich et al 2010;Yang et al 2014;Marsooli and Lin 2018).…”