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.
Bibliographical noteFunding Information:
We are grateful for the thorough and constructive comments of Isabel Marín and an anonymous reviewer. We thank Yeala Shaked and Samuel Albani for helpful and constructive discussions. The data sets discussed in this paper are available at http://www.iui-eilat.ac.il/ Research/NMPAbout.aspx (NMP) and http://www.svivaaqm.net/Default.rtl. aspx. Funding was provided by the Schulich Ocean Studies Centre Initiative grant 3 (to S. S. K. and A. T.) and the Israel Science Foundation grant 927/15 (to A. T.).
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- Atmospheric dust
- Oligotrophic oceans
- Primary production
- Red Sea
- Time series