Temporal‐Scale Analysis of Environmental Controls on Sea Spray Aerosol Production Over the South Pacific Gyre

Abstract

AbstractAn understanding of sea spray aerosol (SSA) production is needed to better assess its influence on climate. Using satellite data, we investigated the production of the coarse mode of aerosol optical depth (AODc), a proxy for SSA, over the pristine South Pacific Gyre. The analysis was done on three time scales: daily, seasonal, and interannual. Scale‐dependent links were shown between the AODc and wind speed (W). AODc and W were positively correlated on both daily and interannual time scales but were significantly anticorrelated on the seasonal time scale. Seasonality of the AODc − W link suggests contribution of other environmental factors. The main variable that could statistically explain trends in AODc on the seasonal time scale was chlorophyll a concentration, which showed a clear negative correlation with AODc. The AODc yield per W unit was clearly reduced when chlorophyll a concentration was high, suggesting a secondary, but important influence of marine biological activity on SSA production.