@article{fdi:010046053,
  title = {{P}atterns of variability of sea surface chlorophyll in the {M}ozambique {C}hannel : a quantitative approach},
  author = {{T}ew-{K}ai, {E}. and {M}arsac, {F}rancis},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e analyse the coupling between sea surface chlorophyll concentration ({CC}) and the physical environment in the {M}ozambique {C}hannel ({MZC}) using statistical models. {S}easonal and interannual patterns are studied along with the role of mesoscale dynamics on enhancement and concentration processes for phytoplankton. {W}e use {S}ea{W}ifs data for {CC} and two other remotely sensed data sets, {TMMI} for sea surface temperature ({SST}) and merged altimetry products for sea level anomaly and geostrophic current. {E}mpirical {O}rthogonal {F}unctions ({EOF}) on {SSC} and {SST} show strong seasonality and partition the {MZC} into three distinct sub-areas. {T}he chlorophyll variability is mostly driven by seasonality, but more in the {N}orth (10 degrees {S}-16 degrees {S}) and {S}outh (24 degrees {S}-30 degrees {S}), and explains respectively 64% and 82% of the {CC} variance. {I}n the {C}entral part (16 degrees {S}-24 degrees {S}), the seasonal signal has less influence (60% variance). {T}here, complex {EOF}s on {S}ea {L}evel {A}nomaly ({SLA}) highlight the role of mesoscale activity (i.e. eddies and filament structures) in the spatial distribution of chlorophyll. {F}ive mesoscale descriptors (shear, stretch, vorticity, deformation and eddy kinetic energy) are derived from the altimetry data to quantify the eddies-related physical patterns in the central region of the {MZC}. {W}e use generalized {A}dditive {M}odels to explain the effect of those features on phytoplankton enhancement. {T}he best model fit (r(2) = 0.73) includes shear, stretch, vorticity and the latitude-longitude interaction as eddies are well structured in space. {C}yclonic eddies associated with negative vorticity are conductive to phytoplankton enhancement by the effect of upwelling in the core notably during the spin-up phase. {T}he interaction between eddies generate strong frontal mixing favourable to the production and aggregation of organic matter. {T}he mesoscale activity is also affected by interannual variability with consequences on {CC}. {W}e highlight a substantial reduction of the {SLA} pattern in 2000-2001 when the {SOI} positive phase is peaking ({N}ina-type pattern). {T}he strong relationship between mesoscale eddies and {SOI} suggests that primary productivity in the {MZC} is also under the influence of distant forcing at a basin scale.},
  keywords = {{M}ozambique {C}hannel ; {S}ea {S}urface chlorophyll ; {M}esoscale ; {S}easonal variability ; {C}limate forcing ; {Q}uantitative approach},
  booktitle = {},
  journal = {{J}ournal of {M}arine {S}ystems},
  volume = {77},
  numero = {1-2},
  pages = {77--88},
  ISSN = {0924-7963},
  year = {2009},
  DOI = {10.1016/j.jmarsys.2008.11.007},
  URL = {https://www.documentation.ird.fr/hor/fdi:010046053},
}