The Hawaii Dust Regime: Patterns and Variability in Aerosol Mineral Dust from MERRA‐2 at Station ALOHA and the Hawaii Aerosol Time‐Series

Dust deposition impacts the biogeochemistry of the surface ocean. Utilising the Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) reanalysis product, Ohnemus and colleagues from the Hawaii Aerosol Time Series (HATS) project examine patterns in surface dust concentrations and precipitation at the Hawaii Ocean Time-series station ALOHA and the surrounding North Pacific. While most dust is present during the spring-summer dusty period associated with Asian outflow, a regular period of fall-winter dustiness is also observed. Time-series analyses show that dust concentrations exhibit little periodicity on multi-year timescales compared to precipitation, indicating that dust’s links with climate indices like Pacific Decadal Oscillatio (PDO) and its effects on upper ocean biogeochemistry in the region may be driven by wet deposition. Forthcoming field results from the HATS project will characterise the dust in 2022 and 2023 and the postdeposition effects on the upper ocean.

Reference: Ohnemus, D.C., Kollman, C., Marsay, C.M., et al. (2025). The
Hawaii dust regime: Patterns and variability in aerosol mineral dust from MERRA‐2 at station ALOHA and the Hawaii aerosol time‐series. J. Geophys. Res.: Atmos., 130, e2024JD041860. https://doi.org/10.1029/2024JD041860