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IT/PNRA

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

  • Permafrost hosts a potentially large pool of microorganisms, which is supposed to be the only life forms known to have retained viability over geological time. Thawing of the permafrost renews their physiological activity and exposes ancient life to modern ecosystems (Gilichinsky et al, 2008). The adaptation mechanisms of microorganisms, at species or population level, make them susceptible to extreme environmental conditions. The survival of microorganisms in permafrost raises the question of what constitutes the limit for microbial life (Steven et al., 2006; Wagner 2008).

  • Characterization of effective precipitation that occurs at ground of Antarctica region, plays a crucial rules in defining and validating global climate models and numerical weather prediction model. The observatory is designed to be set up at the Italian Antarctic station Mario Zucchelli integrating the current instrumentation for weather measurements with other instruments specific for precipitation observations. In particular, a 24-GHz vertical pointing radar, Micro Rain Radar, and an optical disdrometer, Parsivel will be integrated with the advanced weather stations, radiosoundings and the ceilometer. The synergetic use of the set of instruments allows for characterizing precipitation and studying properties of Antarctic precipitation such as dimension, shapes, fall behavior, density of particles, particles size distribution, particles terminal velocity, reflectivity factor and including some information on their vertical extent. The project is for four years, it started in July 2017 and will be active until July 2020, covering the Special Observation Period (SOP) in the Southern Hemisphere of Year of Polar Predicition (YOPP) period. APP can be 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.

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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.

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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.

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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.

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    BIOROSS will explore these unique benthic ecosystems of the Ross Sea focusing on bryozoan, coralline algae, cold-water coral and calcifying sponge bioconstructions and their associated communities in order to build vulnerability maps related to global threats (ocean acidification and global warming). To understand the distribution and extent of the Ross Sea bioconstructions, the international team of BIOROSS will study the Antarctic material already available from PNRA and NIWA collections and take part to a new seabed exploration and collection in the Ross Sea on board of R/V Tangaroa. The multidisciplinary approach will address questions on the structure and functioning of builder species and associated communities by means of a suite of cutting-edge instrumentation for offshore survey and sampling, and state-of-the-art analytical facilities and methods, including multibeam echosounders, towed camera, DNA-barcoding, electron microscopy, computed tomography and mass spectrometry.

  • During Austral Summer1991-92 the National Institute of Oceanography and Applied Geophysics - OGS conducted marine geological and geophysical surveys over the Antarctic Peninsular and the Bransfield Strait. During this cruise approximately 3407 km of 30-fold multichannel seismic reflection (MCS) data were collected in the Antarctic Peninsular and the Bransfield Strait between longitudes 50 and 78 degrees West, and latitudes 60 and 68 degrees South. The surveys were carried out by the research vessel OGS Explora. The digital MCS data were recorded on a SERCEL SN 358 DMX system. The source consisted of an airgun array with a total volume of 71.96 litres fired approximately every 50 meters into a 3000 m cable consisting of 120 hydrophone groups towed at an average depth of 12 m. A GPS + TRANSIT satellite receiver system was used for the navigation. Processing of the data generally followed a conventional sequence: Reformat, Trace-sum with differential NMO, Quality control, Amplitude recovery, Deconvolution, Velocity analysis, NMO corrections, Mute, Trace weighting, Stack, Mixing, Filter, Balance.

  • During Austral Summer1991-92 the National Institute of Oceanography and Applied Geophysics - OGS conducted marine geological and geophysical surveys over the Antarctic Peninsular and the Bransfield Strait. During this cruise approximately 3407 km of 30-fold multichannel seismic reflection (MCS) data were collected in the Antarctic Peninsular and the Bransfield Strait between longitudes 50 and 78 degrees West, and latitudes 60 and 68 degrees South. The surveys were carried out by the research vessel OGS Explora. The digital MCS data were recorded on a SERCEL SN 358 DMX system. The source consisted of an airgun array with a total volume of 71.96 litres fired approximately every 50 meters into a 3000 m cable consisting of 120 hydrophone groups towed at an average depth of 12 m. A GPS + TRANSIT satellite receiver system was used for the navigation. Processing of the data generally followed a conventional sequence: Reformat, Trace-sum with differential NMO, Quality control, Amplitude recovery, Deconvolution, Velocity analysis, NMO corrections, Mute, Trace weighting, Stack, Mixing, Filter, Balance.

  • During Austral Summer1991-92 the National Institute of Oceanography and Applied Geophysics - OGS conducted marine geological and geophysical surveys over the Antarctic Peninsular and the Bransfield Strait. During this cruise approximately 3407 km of 30-fold multichannel seismic reflection (MCS) data were collected in the Antarctic Peninsular and the Bransfield Strait between longitudes 50 and 78 degrees West, and latitudes 60 and 68 degrees South. The surveys were carried out by the research vessel OGS Explora. The digital MCS data were recorded on a SERCEL SN 358 DMX system. The source consisted of an airgun array with a total volume of 71.96 litres fired approximately every 50 meters into a 3000 m cable consisting of 120 hydrophone groups towed at an average depth of 12 m. A GPS + TRANSIT satellite receiver system was used for the navigation. Processing of the data generally followed a conventional sequence: Reformat, Trace-sum with differential NMO, Quality control, Amplitude recovery, Deconvolution, Velocity analysis, NMO corrections, Mute, Trace weighting, Stack, Mixing, Filter, Balance.