Australian atmospheric pressure and sea level data during the 2022 Hunga-Tonga Hunga-Ha'apai volcano tsunami.

On January 15, 2022, an ongoing eruption at the Hunga-Tonga Hunga-Ha'apai volcano generated a large explosion which resulted in a globally observed tsunami and atmospheric pressure wave. This paper presents time series observations of the event from Australia including 503 mean sea level pressure (MSLP) sensors and 103 tide gauges. Data is provided in its original format, which varies between data providers, and a post-processed format with consistent file structure and time zone. High-pass filtered variants of the data are also provided to facilitate study of the pressure wave and tsunami. For a minority of tide gauges the raw sea level data cannot be provided, due to licence restrictions, but high-pass filtered data is always provided. The data provides an important historical record of the volcanic pressure wave and tsunami in Australia. It will be useful for research on atmospheric and ocean waves associated with large volcanic eruptions.

Dispersal and dilution of wastewater from an ocean outfall at Davis Station, Antarctica, and resulting environmental contamination.

The Antarctic Treaty permits the discharge of wastewater into Antarctic marine waters providing that conditions exist for initial dilution and rapid dispersal. We investigated the dilution and dispersal of macerated wastewater around Australia's Davis Station in East Antarctica and examined sediments for evidence of contaminants. Methods used to examine hydrodynamic conditions included current meters, dye release experiments and measurement of sewage-associated microbial markers and surfactants in the water column. We measured marine sediments for metals, nutrients, PBDEs, hydrocarbons and faecal sterols. We propose that if there is adequate dilution and dispersal there would be no significant difference in contaminant concentrations in sediments around the outfall compared to distant control sites. Currents were strongly correlated with prevailing wind conditions. Modelling indicated that diffusivity of wastewater had the greatest effect on dilution factors and that neither discharge rates nor local currents had as much effect. During summer conditions of open water, wastewater is likely to be constrained in a narrow plume close to the coast. Concentrations of sewage bacteria were high around the outfall and detected up to 1.5 km away, along with dye. There were significant differences in sediment concentrations of metals, PBDEs, hydrocarbons, nutrients and faecal sterols between sites within 2 km of the outfall and control sites. We conclude that dilution and dispersal conditions at the Davis outfall are insufficient to prevent the accumulation of contaminants in local sediments and that microbial hazards posed by wastewater are an environmental risk to local wildlife.