No Correlation Between Atmospheric Dust and Surface Ocean Chlorophyll-a in the Oligotrophic Gulf of Aqaba, Northern Red Sea

High-resolution records of daily surface chlorophyll-a (chl-a) concentrations and hourly atmospheric dust concentrations in the Gulf of Aqaba, northern Red Sea, are compared between 2012 and 2016 in order to examine the interplay between atmospheric dust input and surface productivity in this subtropic, nutrient-poor marine ecosystem. Given that lags of days to weeks may occur between the dust input and phytoplankton response, and because of potential biases associated with differences in the sampling resolution, temporal offsets of 1–10 days between the dust and chl-a are examined using smoothing windows between 3 and 31 days. The results suggest that there is no significant positive (or negative) correlation between dust and chl-a surface concentrations, even when allowing for temporal offsets between the two records. This observation pertains to the seasonal as well as the daily time scale (i.e., abrupt dust storms). It is concluded that the role of atmospheric dust as a control on productivity in the Gulf of Aqaba and possibly other oligotrophic regions may have been previously overestimated.