FN Archimer Export Format
PT J
TI Influence of Tropical Instability Waves on Phytoplankton Biomass near the Marquesas Islands
BT 
AF MARTINEZ, Elodie
   RAAPOTO, Hirohiti
   MAES, Christophe
   MAAMAATUAIHUTAPU, Keitapu
AS 1:1,2;2:2;3:1;4:3;
FF 1:;2:;3:;4:;
C1 Univ Brest, IFREMER, CNRS, IRD,LOPS,IUEM, F-29200 Brest, France.
   IRD, UPF, IFREMER, ILM,EIO, F-98702 Tahiti, French Polynesi, France.
   Univ Polynesie Francaise, Lab Geosci Pacifique Sud, F-98702 Faaa, French Polynesi, Fr Polynesia.
C2 UBO, FRANCE
   IRD, FRANCE
   UNIV POLYNESIE FRANCAISE, FRANCE
UM LOPS
IN DOAJ
IF 4.118
TC 7
UR https://archimer.ifremer.fr/doc/00437/54858/56346.pdf
LA English
DT Article
DE ;tropical instability waves;La Nina;chlorophyll-a concentration variability;ocean colour;island mass effect;Marquesas islands;oceanography;satellite observations
AB The Marquesas form an isolated group of small islands in the Central South Pacific where quasi-permanent biological activity is observed. During La Niña events, this biological activity, shown by a net increase of chlorophyll-a concentration (Chl, a proxy of phytoplankton biomass), is particularly strong. It has been hypothesized that this strong activity is due to iron-rich waters advected from the equatorial region to the Marquesas by tropical instability waves (TIWs). Here we investigate this hypothesis over 18 years by combining satellite observations, re-analyses of ocean data, and Lagrangian diagnostics. Four La Niña events ranging from moderate to strong intensity occurred during this period, and our results show that the Chl plume within the archipelago can be indeed influenced by such equatorial advection, but this was observed during the strong 1998 and 2010 La Niña conditions only. Chl spatio-temporal patterns during the occurrence of other TIWs rather suggest the interaction of large-scale forcing events such as an uplift of the thermocline or the enhancement of coastal upwelling induced by the tropical strengthening of the trades with the islands leading to enhancement of phytoplankton biomass within the surface waters. Overall, whatever the conditions, our analyses suggest that the influence of the TIWs is to disperse, stir, and, therefore, modulate the shape of the existing phytoplankton plume 
PY 2018
PD APR
SO Remote Sensing
SN 2072-4292
PU Mdpi
VL 10
IS 4
UT 000435187500152
DI 10.3390/rs10040640
ID 54858
ER

EF