Influences of Physical and Biogeochemical Variability of the Central Red Sea During Winter

The Central Red Sea (CRS) has been characterized by significant eddy activity throughout the year. Weakened wintertime stratification contributes to enhanced vertical exchange. In winter 2014–2015, an extended glider time series in CRS captured this variability. Surface cooling and stronger winds resulted deepening of mixed layer (ML) nearly 90 m. distributions density oxygen suggest that ML did not penetrate nutricline. However, mixing events dispersed phytoplankton from deep CHL maximum (DCM) ML, increasing near-surface chlorophyll. Following events, a mesoscale cyclonic (CE) grew intensified, weakening decreasing depth within eddy. Where CE interfaced with adjacent anticyclonic (AE), DCM subducted beneath shallower AE leading local integrated chlorophyll maximum. Low salinity water containing relatively high CDOM concentrations, originating Gulf Aden, appeared late winter. Mesoscale 160 m upward displacement nutricline ?60 m, well euphotic layer. Remote sensing imagery indicates these eddies contribute horizontal dispersion, including exchange between open sea coastal coral reefs. When is distributed through clear diel variability was evident temporal distribution. Because all biogeochemical responses were apparent at surface, sustained observations essential understand spatial scales their impact on processes.