Key Points

• Mineral dust concentrations from the MERRA-2 atmospheric reanalysis product are investigated at Hawaii’s ocean Station ALOHA back to 1980

• Two semi-annual dust pulses at the site are described and little evidence is seen for long-term shifts in total dust or pulse timing

• Dust concentrations exhibit different periodicities and relationships with precipitation and Pacific Decadal Oscillation index

Plain Language Summary

Dust blown from Earth’s continents fertilizes the oceans with iron and other nutrients needed for plants to grow. This affects ocean ecosystems and is an important control on Earth’s climate. Modern models for the atmosphere report dust very precisely in time and space but rarely address how it affects specific ocean sites over time. We examine these best-available model outputs for a well-studied site at Hawaii to improve our understanding of how dust has varied over the many decades this region has been studied by oceanographic and atmospheric researchers.