TY - JOUR
T1 - Gulf of Mexico Loop Current path variability
AU - Donohue, K. A.
AU - Watts, D. R.
AU - Hamilton, P.
AU - Leben, R.
AU - Kennelly, M.
AU - Lugo-Fernández, A.
N1 - Funding Information:
The principal authors were supported by the Bureau of Ocean Energy Management (BOEM) through contract M08PC20043 with Leidos, Inc. (formerly Science Applications International Corporation, SAIC). The successful deployment and recovery of the array was due to the instrument development and careful preparation and planning by James Singer, Paul Blankanship, E. Sousa, Stuart Bishop, Brian Roderick, Gary Savoie and Cathy Cippolla. R. Leben acknowledges support from BOEM contracts M08PC20043 and M10PC00112 to Leidos Corporation, and NASA Ocean Surface Topography Mission Science Team Grants NNX08AR60G and NNX13AH05G .
Publisher Copyright:
© 2016 Elsevier B.V.
PY - 2016/12/1
Y1 - 2016/12/1
N2 - Loop Current, LC, path variability exhibits a continuum of spatial and temporal scales, all are called meanders in this work. They arise from a variety of processes, including short and long waves, frontal eddies with or without closed cores and developing baroclinic instability. They have been extensively studied with satellite sea surface temperature SST, and height, SSH. Yet, these systems provide an incomplete view into LC meandering: SST measurements are hampered by cloud coverage and low thermal contrast in summer months and SSH measurements by altimeter temporal and spatial resolution. In an effort to resolve LC meander temporal and spatial scales, they are investigated using a mesoscale resolving in situ array deployed in the Gulf of Mexico. The array, which consisted of twenty-five inverted echo sounders with pressure gauges, PIES, and current meter moorings, was deployed April 2009 and recovered in October–November 2011. The broad extent of the array, nominally 89° W to 85° W, 25° N to 27° N, enabled quantitative mapping of the regional circulation. LC meander properties are characterized as a function of spatial distribution of energy, frequency, wavenumber, and phase speed. Dispersion characteristics and meander scales are comparable to those found in the Gulf Stream. Phase speeds increase with frequency and range from 8 to 50 km d−1. Wavelengths associated with each band are as follows: 460 km for the 100 to 40 d band, 350 km for the 40 to 20 d band, 270 km for the 20 to 10 d band and 230 km for the 10 to 3 d band. The strongest variability is in the 100 to 40 d band. Spatially the 100 to 40 d variability is concentrated to east of the Mississippi Fan, growing and propagating downstream along the eastern portion of the LC. Meanders between 40 and 20 d propagate along the full encompassed length of the LC. Their temporal amplitudes peak at the time of LC eddy detachment and separation. Meanders with shorter periods than 20 d do not always propagate along the full encompassed length of the LC, perhaps due to the location of the LC.
AB - Loop Current, LC, path variability exhibits a continuum of spatial and temporal scales, all are called meanders in this work. They arise from a variety of processes, including short and long waves, frontal eddies with or without closed cores and developing baroclinic instability. They have been extensively studied with satellite sea surface temperature SST, and height, SSH. Yet, these systems provide an incomplete view into LC meandering: SST measurements are hampered by cloud coverage and low thermal contrast in summer months and SSH measurements by altimeter temporal and spatial resolution. In an effort to resolve LC meander temporal and spatial scales, they are investigated using a mesoscale resolving in situ array deployed in the Gulf of Mexico. The array, which consisted of twenty-five inverted echo sounders with pressure gauges, PIES, and current meter moorings, was deployed April 2009 and recovered in October–November 2011. The broad extent of the array, nominally 89° W to 85° W, 25° N to 27° N, enabled quantitative mapping of the regional circulation. LC meander properties are characterized as a function of spatial distribution of energy, frequency, wavenumber, and phase speed. Dispersion characteristics and meander scales are comparable to those found in the Gulf Stream. Phase speeds increase with frequency and range from 8 to 50 km d−1. Wavelengths associated with each band are as follows: 460 km for the 100 to 40 d band, 350 km for the 40 to 20 d band, 270 km for the 20 to 10 d band and 230 km for the 10 to 3 d band. The strongest variability is in the 100 to 40 d band. Spatially the 100 to 40 d variability is concentrated to east of the Mississippi Fan, growing and propagating downstream along the eastern portion of the LC. Meanders between 40 and 20 d propagate along the full encompassed length of the LC. Their temporal amplitudes peak at the time of LC eddy detachment and separation. Meanders with shorter periods than 20 d do not always propagate along the full encompassed length of the LC, perhaps due to the location of the LC.
KW - Eddy separation
KW - Loop Current
KW - Meanders
KW - Vertical structure
UR - http://www.scopus.com/inward/record.url?scp=84954287503&partnerID=8YFLogxK
U2 - 10.1016/j.dynatmoce.2015.12.003
DO - 10.1016/j.dynatmoce.2015.12.003
M3 - Article
AN - SCOPUS:84954287503
VL - 76
SP - 174
EP - 194
JO - Dynamics of Atmospheres and Oceans
JF - Dynamics of Atmospheres and Oceans
SN - 0377-0265
ER -