This metadata record is the parent umbrella under which data from the 2008/09, 2013/14 and 2014/15 summer will be housed. See the child records for access to the data. Manmade CO2 has increased ocean acidity by 30% and it is projected to rise 300% by 2100. Antarctic waters will be amongst the earliest and most severely affected by this increase. Microbes are the base of the marine food chain and primary drivers of the biological pump. This project will incubate natural communities of Antarctic marine microbes in minicosms at a range of CO2 concentrations to quantify changes in their structure and function, the physiological responses that drive these changes, and provide input to models that predict effects on biogeochemical cycles and Antarctic food webs

Colonisation of Lake Fletcher, a hypersaline, meromictic lake in the Vestfold Hills, Antarctica, by the calanoid copepod Drepanopus bispinosus, the cyclopoid copepod Oncea curvata and an undescribed cydippid ctenophore is discussed. In 1978, salinity direstly under the ice was 66 ppt and repeated net hauls found no zooplankton. In 1983, adults of D. bispinosus were found, and in 1984, a reproductively active population of this species. Surface water salinity in 1984 was 56 ppt. During winter 1986, surface salinity was 54 ppt and three zooplankton species (D. bispinosus, O curvata and an undescribed cydippid ctenophore) had established populations in the lake. In 1986/87, high tides caused nearby Taynaya Bay to flood into the lake, and three further species (the calanoid, Paralabidocera antarctica, and two harpacticoids, Harpacticus furcatus and Idomene sp.) were found in the lake. It appears that periodic flooding after 1978 caused a salinity decrease in the lake from 66 to 54 ppt, and this enabled some invertebrate species to maintain year-round populations, whereas others require marine incursions to re-establish summer only populations. The fields in this dataset are: Date Salinity Record Species

The distribution and abundance of ice-associated copepods in the fast ice of the Australian Antarctic Territory were investigated over a distance of approximately 650 km between October and December 1995. The six sites where collections were made were: offshore from Mawson station, Larsemann Hills (including Nella Bay), Rauer Islands (ice edge near Filla Is), O'Gorman Rocks and Bluff Island near Davis Station, and Murphy Rocks in the northern Vestfold Hills. Ice cores were obtained using SIPRE ice augers. Five to ten cores were collected along transects several km in length. Thickness of sea ice and snow cover were measured at each sampling site. Chlorophyll a concentrations were determined for each core. Copepods were isolated from the melted core water and identified and counted. Zooplankton tows were also made at each site where cores were collected. Nine species of copepods were identified from the cores. However, of these, only three were recorded regularly: Paralabidocera antarctica, Drescheriella glacialis and Stephos longipes. The abundance of copepods ranged between 0 and 147/L. The highest densities were recorded at the Larsemann Hills and the lowest at Murphy Rocks. Within the cores, the highest abundances were found in the bottom 10 cm of ice, irrespective of the species. Chlorophyll a concentrations ranged between 0.9 and 373 mg/m3. Data available: excel files containing sampling dates, sampling sites and abundances (number per L) of three dominant sea ice copepods, Paralabidocera antarctica, Drescheriella glacialis, Stephos longipes. Data are presented for developmental stages (nauplii, copepodites and adults) where available. Totals are also provided. Vertical distribution in some cores is also provided. Chlorophyll a concentrations (ug/L) provided for most sites. Detailed information about each of the spreadsheets is provided below: The chlorophyll spreadsheet shows chlorophyll concentrations for 5 sites in the AAT. The column headings are: core - reference number of the core collected subsection - depth in the core in cm volume - vol of melted core water volume added - 1 L of filtered seawater for melting % original - amount of total that core water represents (i.e. minus the 1L added) aliquot - volume subsampled for chlorophyll analysis acetone - amount added (mL) for extraction 750, 664, 647, 630 - wavelengths where absorbance was measured chloro a - amount of chlorophyll a in the sample ug/L - chloro a expressed as a concentration The spatial spreadsheet shows species abundances of three copepods at 4 sites N1 to NVI - nauplius stage 1 to 6 of a species CI to CVI - copepodite stage 1 to 6 of a species F or M - female or male of copepodite stage 5 or 6 1,1 etc - cores 1 and 2 from site 1 within a major location (e.g. 2 cores close together in the Larsemann Hills) The temporal spreadsheet shows abundances over time at 2 sites (O'Gorman Rocks, Bluff Is) near Davis and two species (Paralabidocera antarctica and Drescheriella glacialis) on several sampling dates N1 to N3 - total nauplii in each of three cores (i.e. not separated into stages as above) C1 to C3 - total copepodites A1 to A3 - total adults Then at the bottom are the means of each three cores.

Large volumes of water (200 - 500 L) were filtered and fractionated by size for various planktonic components: eukaryotic phytoplankton, prokaryotic picoplankton, and marine viruses. Sample sites were chosen to generate the widest diversity, and included planktonic blooms, oligotrophic zones, small polynyas near sea ice, nearshore areas, and Antarctic bottom water from coastal, canyon and deepwater areas. Half of each sample will be used for DNA library construction, and the other half will be used for meta-proteomic analysis. Random shotgun sequencing of the marine genomic libraries should produce a metagenomic snapshot of planktonic life in a variety of marine habitats. This work was completed as part of ASAC project 2899 (ASAC_2899).