Seasonal variability of chlorophyll a fronts in the Luzon Strait based on satellite observations

摘要

Fronts are important sources of variability in the South China Sea basin, and they play significant roles in controlling bio-physical interactions in the Luzon Strait. We evaluated seasonality of chlorophyll a (chl-a) fronts in the Luzon Strait (LS) based on satellite observations from September 1997 to October 2007. Monthly-mean chl-a concentration at the front was highest in winter (0.8 mg m~(-3)) and lowest in summer (0.3 mg m~(-3)). Additionally, both the probability of frontal occurrence and the seasonal cycle of the gradient between offshore and nearshore chl-a showed that the chl-a front in the LS was the strongest in winter and weakest in summer. Pseudo wind stress played the most important role in shaping the spatial distribution of chl-a concentration, indicating that wind-driven upwelling is the mechanism involved.