Geochemical campaign at McMurdo Dry Valleys (SENECA project) 2023

The geochemical dataset includes: 1. **Soil gas sampling/flux measurements:** Soil gas surveying involves collecting gas samples from the active layer zone to measure the concentrations of various gaseous species in the soil pores. Samples were collected by inserting a steel probe vertically into the soil to a depth ranging from 0.2 m to 0.6 m, depending on the thickness of the active layer. Soil gas samples were taken from the probe using a 60 cc plastic syringe and stored in 15 ml glass vials. The collected gas samples were analyzed with a chromatograph (CP4900 by Varian) to determine the concentrations of the following gaseous species: He, Ne, H2, O2, N2, CH4, C2H2, C2H4, C2H6, CO2, H2S. Radon (222Rn) and Thoron (220Rn) were measured directly in the field using a Durridge RAD7 instrument, performing three or four measurements with a 5-minute integration time. A total of 231 samples were collected during this expedition. Measurements of exhalation flux of CO2 and CH4 from the soil into the atmosphere were conducted using the West System (West Systems TM) accumulation static closed-chamber method. 2. **Continuous monitoring of CO2 concentrations in the active layer:** Continuous monitoring of CO2 concentrations in the bottom of the active layer was recorded. GasPro CO2 Monitoring Probes were designed to measure temperature and CO2 concentration in the unsaturated soil horizon. CO2 concentrations were measured using a Non-Dispersive Infra-Red (NDIR) sensor (model IRCA1 Alphasense). The probes collected one measurement per hour during the period 2020 - 2023 (with gaps) at strategic points within the Taylor and Wright valleys. 3. **Water samples:** We sampled shallow waters from all streams, ponds, and lakes in the studied areas. Physical-chemical parameters such as water temperature, pH, redox potential (Eh), electrical conductivity, and alkalinity were determined in situ. Water samples were collected and stored in high-density polyethylene flasks for laboratory analysis in the following quantities: - 2 flasks of 50 ml for major anions and cations - 1 flask of 50 ml for minor and trace elements - 1 flask of 100 ml for isotopic analyses - 1 serum glass bottle of 155 ml for dissolved gases in the water. Major anions and cations were sampled from filtered and acidified samples, respectively. Minor and trace elements were collected from filtered and acidified samples. An unfiltered sample was collected for the determination of stable isotope analyses (18O, D). The chemical composition analysis of dissolved gases (He, Ne, H2, O2, N2, CH4, CO2), extracted from water samples collected in serum glass bottles and sealed with gas-tight rubber plugs according to the method of Capasso and Inguaggiato (1998), was carried out in the Scott Base Laboratory using an Agilent 4900 CP Micro-gas chromatograph equipped with two TCDs and Ar as carrier gas. The dissolved gas composition (expressed in mmol/L at STP) was calculated from the composition of the exsolved gas phase based on the solubility coefficient of each gas compound (Whitfield, 1978). The analytical error was <5%. A total of 15 water samples were collected during this expedition.

Pelagic ecosystem monitoring of the key species of Middle Trophic Level in the Ross Sea Marine Protected Area

The Middle Trophic Level of the Ross Sea is still not well known but it mainly characterized by two species of Krill: Euphausia superba, Euphausia Crystallorophias. These species are a key food source for a wide variety of marine birds and mammals in the Ross Sea. For this reason, it's necessary to improve the knowledge on abundance and spatial distribution of MTL species, and their interconnection with environmental parameters to understand the main drivers of the reproductive success and migrations of these species. In this project, an acoustic survey, a synoptic net sampling and a CTD/XBT samplings were carried out following the standard protocols indicated by CCAMLR. Acoustic monitoring was performed at five frequencies: 38, 70, 120, 200 and 333 kHz. Targeted net samplings were performed to validate the preliminary species allocation of the aggregations observed on the echosounder screen. Biometric measures of krill samples was made on board and samples were taken for further analysis. CTD and XBT data was collected and elaborated to characterize water masses and to study the possible influences of the distribution of the main oceanographic parameters on MTL species.

UWBRAD 500-2000 MHz brightness temperature measurements during the ISSIUMAX campaign in Terra Nova Bay, Antarctica

The dataset contains 500-2000 MHz brightness temperature measurements gathered by the Ultra-Wideband Software Defined Microwave Radiometer (UWBRAD) during the Ice Sheet and Sea Ice Airborne Microwave eXperiment (ISSIUMAX) in Terra Nova Bay, Antarctica. The published dataset is in ascii format and consists of geolocated nadiral brightness temperature measurements collected over 12 sub-bands whose central frequencies are 560, 660, 820, 900, 1180, 1240, 1370, 1500, 1630, 1740, 1860, and 1950 MHz. Only measurements with a viewing angle within 5 deg with respect to nadir are reported.

Vertically pointing doppler radar profiles (24 GHz Metek MRR-2) at Mario Zucchelli Station, aggregated to 5min, monthly netCDF archive

Vertical profiles along the first kilometre of atmosphere above the ground (from 105 to 1050 m a.g.l.) of equivalent radar reflectivity factor (Ze), Doppler velocity (W) and Doppler spectral width (Sw) from a 24-GHz vertically pointing Micro Rain Radar MRR-2 by METEK GmbH positioned at Mario Zucchelli Station (Antarctica).

Ecomorphological Analysis and development of virtual mobile models of buccal apparatus of notothenioid fish species (EMPHASIS)

The EMPHASIS project focuses on the ecomorphology of the feeding apparatus of Notothenioidea, a suborder of teleost fishes endemic to the Southern Ocean that have colonized available ecological niches and habitats during their adaptive radiation. Ecomorphology is the science that investigates the reciprocal relationship between the environment and the forms of organisms, allowing insights into their evolutionary history, biodiversity, and relationships between form and function. The research activity involves a comparative analysis of the feeding apparatus in species representative of various phyletic lineages, and the study of the relationships between morphology, function and specific performance during feeding. Based on the results of the analysis, three-dimensional digitally supported models of the structures involved in feeding activity was developed.

Microbial colonization of benthic ANTarctic environments: response of microbial abundances, diversity, activities and larval settlement to natural or anthropogenic disturbances and search for secondary metabolites (ANT-Biofilm, PNRA16_00105)

The ANT-Biofilm research project (PNRA16_00105) concerned the study of microbial colonization processes in coastal environments of Terra Nova Bay (Ross Sea), through the analysis of the microbial biofilm (bacteria, microalgae) and macrobenthic settlement on plastic substrates, with the aim of determining their possible variations caused by natural or anthropogenic disturbances (variations in salinity or the presence of contaminants, respectively). Microbial biofilms, which play a key role as a substrate for larval settlement of many species of invertebrates, constitute hot-spots of microbial diversity; and it is also known that the communities a microbial are capable of responding rapidly to changing environmental conditions, acting as potential "sentinels" of natural or anthropic perturbations that recently are threatening the Antarctic biota. During the first year of activity (XXXIII Italian expedition, November 2017) stainless steel structures were fixed on the seabed of Road Bay and Tethys Bay mounting panels of artificial substrates (Polyvinyl Chloride, PVC and PolyEthylene, PE) for colonization, which during the XXXIV expedition (November 2018) were retrieved in order to study the fouling formation processes at different levels of biological complexity (from microbial community including bacteria and microalgae to benthic invertebrates) and to evaluate their evolution in two coastal sites differently exposed to natural or anthropogenic forcings.

Particle size and velocity distributions from a Thies Clima 3D Stereo disdrometer installed at the Casale Calore site in L'Aquila (Italy) for one year of testing, monthly netCDF archive

Disdrometric data from a Thies Clima 3D Stereo with 22 size classes and 20 velocity classes positioned at L'Aquila (Italy, 42.3831 N, 13.3148 E, 683 m a.s.l.), with monthly spectra and ancillary information.

Particle size and velocity distributions from an OTT Parsivel optical disdrometer located at Mario Zucchelli Station, aggregated to 5min, monthly netCDF archive

Disdrometric data from an OTT Parsivel with 32 size classes and 32 velocity classes positioned at Mario Zucchelli Station (Antarctica), with monthly spectra and particle size distributions (PSD).