During the 2007–08 Spanish Antarctic campaign, two moorings of bottom pressure sensors were carried out over a ten week period. This paper presents the results of the tidal analysis from sea level records obtained at Deception and Livingston islands (South Shetland Islands, Antarctica). The main objective of this paper is to present a detailed study of the tidal characteristics at these two islands, for which statistical and harmonic analysis techniques are applied to the tidal records. A geodetic network was used to reference the pressure sensors. Geometric levelling, with an accuracy of 1 mm, allowed us to link the tidal marks with geodetic vertices located on Livingston and Deception islands. The amplitudes and phase lags obtained by harmonic analysis are compared to the harmonic constants of several coastal stations and co-tidal and co-range charts. Results show an evident influence of tides in the sea level signal, with a clear mixed semi-diurnal behaviour and a daily inequality between high and low waters. Measurements of salinity and temperature were made using electronic sensors. Results from this study showed that salinity and temperature were strongly influenced by tides. Seawater temperature varied in a manner that was consistent with the time series of residual bottom pressure.

A detailed study is presented of the tidal constituents for Livingston and Deception Islands (Antarctica) obtained at the LIVMAR and DECMAR tide gauge stations. Data were acquired with tide gauge pressure sensors, and calculated from a long time series of 798 days of data-logging, using the least-squares harmonic estimation method. The results show an improvement over previous results in the region. Seventy tidal constituents were obtained, of which 19 were the most representative with amplitudes greater than 1 cm and a contribution of 93% of the wave energy. In both stations, it was confirmed that the tides are mixed, with a semi-diurnal behavior. The tidal gauge benchmarks (TGBMs) were linked to vertical and horizontal Antarctic Geodetic Networks, which provides a very important contribution for geodetic, oceanographic and hydrographic studies in the area.

A methodology to determine the full energy peak efficiency (FEPE) for precise gamma spectrometry measurements of environmental samples with high-purity germanium (HPGe) detector, valid when this efficiency depends on the energy of the radiation E, the height of the cylindrical sample H, and its density ρ, is introduced. The methodology consists of an initial calibration as a function of E and H and the application of a self-attenuation factor, depending on the density of the sample ρ, in order to correct for the different attenuation of the generic sample in relation to the measured standard. The obtained efficiency can be used in the whole range of interest studied, E = 120–2000 keV, H = 1–5 cm, and ρ = 0.8–1.7 g/cm³, being its uncertainty below 5%. The efficiency has been checked by the measurement of standards, resulting in a good agreement between experimental and expected activities. The described methodology can be extended to similar situations when samples show geometric and compaction differences.