| Summary: | Progress Code: completed Statement: Samples were stranded in Antarctic for greater than 12 months but were stored always below -80C. Pigment signatures (HPLC) do not show any signs of degradation. And data quality is ok. However, sampling location x = 70m, y = 64m sampled on 23/11/2015 should be excluded from any further analyses due to unrealistic data in sea ice interior sections. csv copies of some of the spreadsheets have been made, and are available in the download file. Purpose The main objective for the collection of this dataset was to develop algorithms to estimate ice algal biomass from hyperspectral under-ice radiance measurements. Field-based sampling: As part of Australian Antarctic Science project # 4298, a total number of 44 sea ice sites were sampled for bio-optical measurements along 4 transects on land-fast sea ice off Davis Station (Antarctica) during November – December 2015. Measurements included simultaneous hyperspectral down-welling (ice surface) irradiance (triplicate) and under-ice radiance (triplicate) measurements (320 – 900 nm, 3.3 nm resolution) with a TriOS ACC and Trios ARC radiometer, respectively. The radiance measurements were conducted with the TriOS ARC radiometer mounted onto an L-shaped arm (for deployment details see Melbourne-Thomas et al. 2015). Subsequently, snow thickness was measured with a ruler and an ice core was collected directly above the radiometer location. Sea-ice freeboard (tape measure) and ice thickness (ice core length) were also recorded. Ice cores (9 cm internal diameter) were cut into sections, and these were melted in the dark at +4 degrees C, filtered onto GFF filters and then used to measure ice algal pigment content (using High Performance Liquid Chromatography (HPLC) and spectral ice algal absorption coefficients (ap, ad, aph) for entire vertical profiles or for the lower-most 0.1 m of ice cores. The location of the sampling grid had its origin (x=0, y=0) at GPS position: -68.568904, 77.945439. Transects (128m – 512 m in length) started at ...
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