@article{fdi:010089544,
  title = {{S}patial and temporal variability in mode-1 and mode-2 internal solitary waves from {MODIS}-{T}erra sun glint off the {A}mazon shelf},
  author = {de {M}acedo, {C}. {R}. and {K}och {L}arrouy, {A}riane and da {S}ilva, {J}. {C}. {B}. and {M}agalhaes, {J}. {M}. and {L}entini, {C}. {A}. {D}. and {T}ran, {T}. {K}. and {R}osa, {M}. {C}. {B}. and {V}antrepotte, {V}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he {A}mazon shelf is a key region for intense internal tides ({IT}s) and nonlinear internal solitary wave ({ISW}s) generation associated with them. {T}he region shows well-marked seasonal variability (from {M}arch to {J}uly, {MAMJJ}, and from {A}ugust to {D}ecember, {ASOND}) of the circulation and stratification, which can both induce changes in the {ISW} physical characteristics. {T}he description of the seasonal and neap-spring tidal variability in the {ISW}s off the {A}mazon shelf is performed for the first time using a meaningful data set composed of 140 {MODIS}-{T}erra imagery from 2005 to 2021, where about 500 {ISW} signatures were identified in the sun glint region. {P}revious studies have documented the existence of mode-1 {ISW}s, but the region appears as a newly described hotspot for mode-2 {ISW}s. {ISW} packets separated by typical mode-1 (95-170 km; 2.1-3.8 m s-1) and mode-2 (46-85 km; 1.0-1.9 m s-1) {IT} wavelengths have been identified and mapped coming from different {IT} generation sites. {F}or each {ISW}, a group of waves (3 to 10) is generally follows the largest crest. {T}he intra-packet distance between each wave in the group is about 10 to 20 km. {R}egions of higher occurrence of {ISW}s are spaced by a {IT} mode-1 wavelength. {W}e make the assumption that it might correspond to the {IT} reflection beams at the surface, which may generate newer {ISW}s. {T}he mean mode-1 and mode-2 inter-packet distances do not show significant differences according to their {IT} generation sites. {T}he {ISW} activity is higher (more than 60 % of signatures) during spring tides than neap tides. {I}n the region under the influence of the {N}orth {E}quatorial {C}ounter {C}urrent ({NECC}), {ISW}s are separated by a mean mode-1 {IT} wavelength which is 14.3 % higher during {ASOND} than during {MAMJJ} due to a deeper thermocline and the reinforcement of the {NECC}. {T}hese {ISW}s are also characterized by a wider inter-packet distance distribution (higher standard deviation) that may be related to the stronger eddy kinetic energy ({EKE}) during {ASOND} compared to {MAMJJ}. {T}he mean inter-packet distance of mode-2 {ISW}s remains almost unchanged during the two seasons, but the inter-packet distance distribution is wider in {ASOND} than in {MAMJJ} as for mode 1. {N}ote that these results need to be treated with caution, as only few occurrences of mode-2 waves were found during {MAMJJ}. {I}n the region of the {NECC}, the direction of propagation for all modes is very similar in {MAMJJ} (about 30 circle clockwise from the north), whereas, for {ASOND}, the {ISW}s propagate in a wider pathway (from 0 to 60 circle clockwise from the north), due to a much larger eddy activity. {D}uring {ASOND}, as the background flux goes further east, the inter-packet distances become larger (4 % for mode 1 and 7.8 % for mode 2). {T}hese results show that the reinforcement of the {NECC} in {ASOND} appears to play a role in diverting the waves towards the east, increasing their phase velocities and their eastern traveling direction component when compared to {MAMJJ}. {C}alculations of the {IT} velocities using the {T}aylor-{G}oldstein equation supported our results regarding the presence of {ISW}s associated with mode-2 {IT}s and additionally the {IT} seasonal variability.},
  keywords = {{ATLANTIQUE} ; {BRESIL} ; {AMZONE}},
  booktitle = {},
  journal = {{O}cean {S}cience},
  volume = {19},
  numero = {5},
  pages = {1357--1374},
  ISSN = {1812-0784},
  year = {2023},
  DOI = {10.5194/os-19-1357-2023},
  URL = {https://www.documentation.ird.fr/hor/fdi:010089544},
}