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The transport and delivery of low‐abundance, bioactive trace elements to the surface ocean by aerosol mineral dust is a major planetary control over marine primary production and hence the global carbon cycle. Variations in the concentration of atmospheric dust have established links to global climate over geologic timescales and to regional biogeographic shifts over seasonal timescales. Constraining atmospheric dust variability is thus of high value to understanding oceanographic systems, especially vast, constitutively low‐nutrient subtropical gyre ecosystems and high‐nutrient/low‐chlorophyll ecosystems where availability of the trace element iron is a dominant ecological control. Here we leverage the MERRA‐2 reanalysis product to examine over four decades of surface‐level atmospheric mineral dust concentrations in a domain of the subtropical North Pacific centered at Ocean Station ALOHA. This study region has been sampled regularly since the mid‐1980s and was the site of the Hawaii Aerosol Time‐Series (HATS) project in 2022–2023. Two unequal semi‐annual periods of elevated dust evident in the long‐term results are described and constrained. We look for evidence of shifts in total and seasonal atmospheric dust abundances or in the timing of the onset of the dominant spring/summer dusty period, finding year‐to‐year variations but little evidence for long‐term trends. We observe significant but complex relationships between the Pacific Decadal Oscillation (PDO) index and both dust and precipitation. The 2022 calendar year was among the dustiest years for the study domain in the preceding two decades and, by contrast, 2023 exhibited a significant early spring lull in dust. 

The Arecibo Pisces Perseus Supercluster Survey (APPSS) is an HI survey measuring galaxy infall into the filament and clusters. Galaxies were selected for HI observations based on their location within the Pisces Perseus supercluster and SDSS and GALEX colors predictive of cold gas content. Most of the HI observations were conducted at Arecibo using the L Band Wide receiver, with some high-declination coverage provided by Green Bank. The observations provide increased sensitivity compared to ALFALFA blind survey data. For this project, we investigated a subset of 132 APPSS galaxies with declinations near 27 degrees. Using custom data reduction and analysis tools developed for the Undergraduate ALFALFA Team, we determined the following information for galaxies in our subset: systemic velocity, line width, integrated flux density, HI mass, and gas fraction (or corresponding limits for non-detections). We calculate our HI detection fraction and mean gas fraction as a function of stellar mass and compare to previous results. We investigate the distribution of systemic velocities for our galaxies with their location on the sky. Finally, we discuss several interesting sources from our subset of APPSS galaxies. This work has been supported by NSF grants AST-1211005, AST-1637299, and AST-1637339