| Summary: | Progress Code: completed Statement: The values provided in temporal and spatial coverage are approximate only. Taken from the 2008-2009 Progress Report: Variations to work plan or objectives: 1. to accelerate our development program, we deployed two Pulse test moorings instead of one. Both designs were successful in terms of surviving the high seas, and we are currently evaluating mooring accelerometer data to choose the best design in terms of minimising stresses on instruments. 2. we moved the deep sediment trap mooring from its usual site (near 47 S, 140 E) to a site closer to Tasmania (near 45 S, 146 E). We did this for logistical reasons - to allow for deployment from the Marine Trials voyage, but we also expect scientific gains because this site is in the region where waters from the East Australian Current extension pass westward south of Tasmania, and thus we will be able to compare sinking particle fluxes from these waters with those from the more southerly, cooler Subantarctic waters studied previously. This is particularly advantageous because these warmer westerly flows are expected to increase in future as a result of climate warming, and thus this work gets us an early look at possible ecosystem and carbon cycling responses. Field work: Three moorings were deployed from the Aurora Australis marine science trials voyage, 3-12 Oct 2008. Mooring 'SAZ 45-11' was deployed at 44.8 deg S, 145 deg E and is due to be recovered in September 2009. It was instrumented with 3 Mclane time series sediment traps, 2 Indented Rotating Sphere sediment traps in settling velocity mode, and 1 current meter. The two PULSE engineering test moorings were deployed at PULSE5-Light - 44.2 deg S, 146.4 deg E. PULSE5-Heavy - 44.2 deg S, 146.5 deg E. and recovered in April 2009 with Marine National Facility support. Laboratory activity/analysis: A method to analyse the sediment trap samples for silicon and aluminium with micro x-ray fluorescence (uXRF) has been evaluated, and samples are currently being analysed. This will ...
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