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Atmospheric conditions

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  • Anthropogenic microparticles (AMs) were found for the first time in specimens of Trematomus bernacchii collected in 1998 in the Ross Sea (Antarctica) and stored in the Antarctic Environmental Specimen Bank. Most of the identified AMs were fibers of natural and synthetic origin. The natural AMs were cellulosic, the synthetic ones were polyester, polypropylene, polypropylene/polyester, and cellulose acetate. The presence of dyes in the natural AMs indicates their anthropogenic origin. Five industrial dyes were identified by Raman spectroscopy with Indigo occurring in most of them (55%). Our research not only adds further data to the ongoing knowledge of pollution levels in the Antarctic ecosystem, it provides an interesting snapshot of the past, highlighting that microplastics and anthropogenic fiber pollution had already entered the Antarctic marine food web at the end of the ‘90 s. These findings therefore establish the foundations for understand the changes in marine litter pollution over time.

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    This research addressed a feasibility study for a remote monitoring system based on acoustic tomography to be used in antarctic regions. The analysis of data collected during PNRA oceanographic campaigns provided the environmental scenarios and the oceanographic processes to be successfully monitored by means of acoustic tomography and the appropriate information and data to initialize the tomographic processor. The case studies regarded High Salinity Shelf Water formation process in Terra Nova Bay polynya. The simplified but realistic environmental scenario considered a 1000 m deep area with a flat bottom. The dense water formation area was defined by a strong vertical salinity gradient in the surface, while in the areas outside, temperature and salinity were considered constant in depth leading to an almost linear increasing sound speed profile. At this stage of study, the possible presence of ice layer covering the area is not expected to have any significant effect on the propagation prediction, so it was not considered. Simulations were carried out with a beam model (Bellhop) which is well suited for active sonar modelling and ocean acoustic tomography in a range dependent environment. Each simulation involves the use of an acoustic source and a receiving station (tomographic pair) consisting of a vertical array of hydrophones. By measuring the travel time relative to different scenarios, the analysis aimed at understanding if the detection of the oceanographic phenomenon is feasible. In particular, the study aimed at determining the best compromise between acoustic frequencies, sensors number and geometrical configuration, in order to achieve the desired spatial-temporal resolution useful to detect the presence of dense water masses. An acoustic system configuration consisting of an acoustic source transmitting a pulse with a carrier frequency of 10 kHz, and of a receiving array made of 6 hydrophones resulted to be appropriate, while the minimum size of detectable Dense Water Mass is 0.5 km. In particular, the conducted sensitivity study evidences that the measure of travel time of acoustic rays can be successfully exploited to detect the presence of a dense water mass in a polynya area Acoustic tomography thus provides “images” of wide areas in the inner ocean for long periods and with an high temporal resolution; in addition it permits to reconstruct the sound speed field even in the upper layers where direct measurements cannot be performed as instruments are at risk of damage. It can then be consider a powerful mean of observation that well integrates conventional in situ measurements. Preliminar investigation on the applicability of this methodology in Terranova Bay polynya demonstrated that it is able to resolve the vertical structure of water column with a good precision.

  • Emerging COntaminants in Antarctic Snow: sources and TRAnsport (ECO AS:TRA) Prog. PNRA18_00229 Snow samples

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    The project aims to determine the mass balance components in the Dome C drainage area and to study and monitor local glaciers in Victoria Land. The goal is to define the mass balance of the ice cap through the analysis of its altimetric variation with satellite systems and through the determination of the values of the positive (snow accumulation) and negative (flow of glaciers to the anchor line) components of the balance mass. Trought the study of the snow cores (collected as part of the ITASE project (XVII/XVIII expedition)), was determined the annual stratigraphy and evaluated the snow accumulation, the isotopic temperature and the chemical composition of the snow cores. Moreover analysis of geophysical data (GPR, GPS, RES, spectroradiometry) and remote sensing data were carried out for the study of the variability of snow accumulation, of the dynamics of the ice cap and of the flow of glaciers to the anchor line.

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    The UV spectral measurement at ground it’s a diffuse method to determine the stratospheric ozone content. The main objective of the project was the assembling of the UV filter radiometer (named F-RAD) for the measurements of the Sun global irradiance at the Mario Zucchelli Station (MZS), Terranova Bay, Antarctica. The main parts of the instruments are: the entrance radiation optical system, the filters selecting the wavelength of interest and the control system, hardware and software, governing all the measurement steps. The main requirements were: time resolution of one minute and spectral resolution less than 1 nm. The researchers of the project have been participated at two Antarctica campaign, the XXI campaign, 2005, and the XXV campaign, 2009. - XXI Campaign: the radiometer was tested in the Antarctica environment in order to check the reliability of the different components and the optical stability of the filters. - XXV Campaign: the radiometer F-RAD was definitively placed on the roof of one of the MZS building and connected with the Local Area Network of the base. the UV data were daily downloaded in Italy. The spectral UV data acquired with high time resolution, each wavelength was measured 1430 time per day and high spectral resolution, the filters have a FWHM of 0.5- 0.8 nm. F-RAD was placed in Antarctica in November 2009 and works properly, the different parameters are checked daily.

  • Calibrated (in unit of solar disk brightness) measurements of the sky brightness at DOME C as obtained by the ESCAPE experiment during the campaign 2018-2019

  • Calibrated (in unit of solar disk brightness) measurements of the sky brightness at DOME C as obtained by the ESCAPE experiment during the campaign 2019-2020

  • Surface ozone data, collected through a UV-absorption analyzer (49i or 49c)

  • The knowledge of properties and quantitative measurement of solid precipitation in Antarctica is of fundamental importance as precipitation represents the main input of Antarctic ice sheet mass, the variations of which have a direct and non-negligible effect on the average level of the oceans at global scale. Characterization and quantification of the precipitation is crucial in defining and validating global climate models and numerical weather prediction models, as well as anchoring and validating space-borne remote sensing estimates from missions like CloudSAT and EarthCARE. A snow and cloud microphysics observatory has been set up at the Italian Antarctic station Mario Zucchelli (MZS), integrating the pre-existing instrumentation for weather measurements. In particular, a 24-GHz vertical pointing Doppler radar, the METEK's Micro Rain Radar 2 (MRR-2), and a laser disdrometer, the OTT Parsivel, have been integrated with the advanced weather stations, radiosoundings and the ceilometer already present at MZS. The synergy between the set of instruments allows for characterizing precipitation and studying properties of Antarctic precipitation such as dimension, shape, fall behavior, particle number density, particles size distribution, particles terminal velocity, reflectivity factor and information on their vertical extent. APP started as a four-year project in July 2017, covering the Special Observation Period (SOP) in the Southern Hemisphere of Year of Polar Predicition (YOPP) period. APP can provide specific measurements for precipitation occurring over the Antarctic coast at high temporal resolution, in particular specific snow products such as snow rate, snow depth and their water equivalent. In November 2023 the observatory received an additional instrument, the Thies Clima 3D Stereo imaging disdrometer, which was previously installed for one year in Italy for testing, at the Casale Calore (AQ) meteorological observation site from the University of L'Aquila. The research team of the first two years was coordinated by Nicoletta Roberto, with operational units at the Rome unit of the CNR-ISAC (Luca Baldini, Elisa Adirosi, Stefano Dietrich) and at the Department of Physics and Astronomy of the University of Bologna (Rolando Rizzi, Federico Porcù, Tiziano Maestri, Alessandro Bracci). From 2020 the coordination of the project passed to Luca Baldini (CNR-ISAC) and the work team was extended with the research fellows Giacomo Roversi and Sabina Angeloni.

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    Exploratory study for the development of technologies required for biological, geological and physical-chemical entry and sampling in subglacial lakes under high contamination-free conditions. The proposed activity is part of an international initiative, promoted and sponsored by SCAR and COMNAP in which Italy is also represented. The scientific objective is the development of miniaturized technologies for the execution of chemical-physical-biological measurements and of remoting technologies for the transport of instrumentation to the operational site, possibly enabling "in situ" sampling and material recovery operations.