Abstract

QUETZ-QUE, Santiago J. et al. Seasonal and interannual variability in chlorophyll concentration and primary productivity off Campeche, Gulf of Mexico. Cienc. mar [online]. 2022, vol.48, e3168.  Epub Nov 17, 2023. ISSN 0185-3880.  https://doi.org/10.7773/cm.y2022.3168.

The objective of this work was to characterize the spatiotemporal variability in satellite-derived chlorophyll concentration (Chlsat), primary productivity (PP), sea surface temperature (SST), and sea surface height (SSH) in the Campeche Bank from July 2002 to December 2018. Monthly composites of Chlsat and SST (MODIS-Aqua sensor) and SSH (COPERNICUS) were downloaded. PP compositions were downloaded from the Oregon State University web page. Four transects running perpendicular (T1 to T4) and 1 parallel (T5) to the coast of Campeche were studied. Time series and Hovmöller diagrams were constructed to study the spatial and temporal variations. The Chlsat in T1 to T4 showed a clear separation between an inner zone (0-60 km) and an outer zone (60-200 km). The inner neritic zone showed maximum Chlsat (>2.5 mg·m-3) and PP (>2 g C·m-2·d-1) values in the rainy season and minimum values in the dry season (<2 mg·m-3 and <2 g C·m-2·d-1, respectively) because freshwater input in the inner zone provides nutrients for phytoplankton growth. The outer neritic zone showed the highest Chlsat (>0.6 mg·m-3) and PP (>0.7 g C·m-2·d-1) values during cold fronts and the lowest during the dry season (<0.3 mg·m-3 and <0.4 g C·m-2·d-1) because cold fronts mix the water column and thus carry nutrients into the euphotic zone. SST showed maximum values (>30 °C) during the rainy season and minimum values (<22 °C) during cold fronts; maximum SSH (>0.40 m) occurred during cold fronts, and minimum SSH (<0.25 m) occurred during the dry season.

Keywords : chlorophyll concentration; sea surface temperature; sea surface height; area off Campeche; Gulf of Mexico.