Surface Level Atmospheric Dimethylsulfide Measurements on the Great Barrier Reef
A series of atmospheric dimethylsulfide (DMS) data sets were collected on the Great Barrier Reef (GBR) at intervals between March 2012 and February 2018. These data sets were mainly collected at the Heron Island Research Station on the southern GBR (23.44°S, 151.91°E), although one dataset was collected from the northern GBR at a shore site between Mission and Garners Beach (17.82°S, 146.10°E). The DMS data are accompanied by meteorological data, solar irradiance, tidal predictions and coarse mode (0.5-2.5 µm) aerosol data.
The 2016 and 2018 datasets were collected as part of an internationally supported research project titled “the GBR as a significant source of climatically relevant aerosol particles”, which came about as a result of funding gained from the Australian Research Council (ARC) Discovery Projects (DP150101649). The administering organisation was the Queensland University of Technology. During 2016, field observations included both sea and land based monitoring platforms; these comprised a 31 day voyage of the RV Investigator (Marine National Facility, IN2016_V05) and a coastal ground-based station at Mission Beach (AIR-BOX, LE150100048). These platforms enabled observation of the transformation of air-masses as they travelled either from inland or from the Pacific Ocean over the GBR.
The aim of the Discovery Project was to determine the mechanisms of new particle production from one of the biggest ecosystems in Australia, the GBR, and to establish whether marine aerosol along the Queensland coast is coral-derived. DMS is a metabolic product of marine phytoplankton and coral, and when it is exchanged from the sea to the atmosphere it can generate new aerosol particles that can ultimately affect cloud condensation nuclei concentrations. DMS is, therefore, a climate active compound that has the potential to affect cloud formation, cloud microphysical properties, and the hydrological cycle of the GBR.
The Discovery Project was the first major field program to intensively measure atmospheric composition over the GBR to contribute to understanding the interaction between the atmosphere and the biosphere. Observations acquired to gain a better understanding of the role of atmospheric composition in the GBR region, are currently being processed and collated by the various investigators involved.
Key science questions of the Discovery Project were:
- 1. Do aerosols along the north Queensland coast have a significant signature that is coral-derived?
- 2. How does this aerosol change its physicochemical properties as winds carry it from the reefs to the north Queensland rainforests?
- 3. What is the significance of the GBR ecosystem as a source of aerosol particles?
The data provided in this collection contributes to the investigation of these questions, and questions presented in my PhD thesis.
Acknowledgements: Elisabeth Deschaseaux (SCU) contributed to collection of the Heron Island data by organizing field trips and providing field work assistance. The staff of the Heron Island Research Station (UQ) are also acknowledged for providing logistical assistance to enable successful completion of our field studies.