81 research outputs found
TEMPORAL EVOLUTION OF THERMAL STRUCTURES AND WINTER HEAT CONTENT CHANGE FROM VOS-XBT DATA IN THE CENTRAL MEDITERRANEAN SEA
Seasonal and year-to-year time evolution of the
thermal structure, including the heat content change in the
upper water column and its relationship with the surface net
heat fluxes, have been studied at five locations in the central
Mediterranean Sea. The study is based on temperature
profiles collected during XBT surveys (eXpendable Bathy-
Thermograph) carried out on ships of opportunity, in the
framework of the MFSPP (Mediterranean Forecasting System
Pilot Project), between September 1999 and May 2001.
The five investigated zones are located in the southern Adriatic,
NW Ionian, southern and northern Tyrrhenian, and Ligurian
Sea. Gradual erosion of the thermocline in autumn,
formation of a mixed layer in winter, and the onset of the
stratification in spring, are common properties of the temporal
evolution of thermal structures at all five locations. Moreover,
in the southern Adriatic, a deep convection took place
down to about 600m in winter 1999/2000. On the other
hand, mild climatic conditions and small surface heat loss
in autumn and winter 2000/2001 drastically reduced a mixing/
convection depth which hardly reached 200 m. Simultaneously,
the NW Ionian remained slightly stratified throughout
the winter period. The heat storage rate in the upper portion
of the water column (down to 450 m) is compared with
the air-sea net heat flux at a monthly scale. A heat content
decrease is determined by the surface heat loss, and the processes
such as lateral advection, or upwelling of the colder
waters through the base of the water column (for example,
in the southern Adriatic and Ionian Seas). Elsewhere (for
example, in the northern Tyrrhenian and Ligurian Seas), the
upwelling does not contribute significantly to the heat balance
within the water column, since the vertical temperature
gradients in deeper layers are negligible
A Network of X-Band Meteorological Radars to Support the Motorway System (Campania Region Meteorological Radar Network Project)
he transport sector and road infrastructures are very sensitive to the issues connected to the atmospheric conditions. The latter constitute a source of relevant risk, especially for roads running in mountainous areas, where a wide spectrum of meteorological phenomena, such as rain showers, snow, hail, wind gusts and ice, threatens driversâ safety. In such contexts, to face out critical situations it is essential to develop a monitoring system that is able to capillary surveil specific sectors or very small basins, providing real time information that may be crucial to preserve lives and assets. In this work, we present the results of the âCampania Region Meteorological Radar Networkâ, which is focused on the development of X-band radar-based meteorological products that can support highway traffic management and maintenance. The X-band measurements provided by two single-polarization systems, properly integrated with the observations supplied by disdrometers and conventional automatic weather stations, were involved in the following main tasks: (i) the development of a radar composite product; (ii) the devise of a probability of hail index; (iii) the real time discrimination of precipitation type (rain, mixed and snow); (iv) the development of a snowfall rate estimator. The performance of these products was assessed for two case studies, related to a relevant summer hailstorm (which occurred on 1 August 2020) and to a winter precipitation event (which occurred on 13 February 2021). In both cases, the X-band radar-based tools proved to be useful for the stakeholders involved in the management of highway traffic, providing a reliable characterization of precipitation events and of the fast-changing vertical structure of convective cells
The influence of the Drygalski Ice Tongue on the local ocean
ABSTRACT
The Drygalski Ice Tongue presents an ~80 km long floating obstacle to alongshore flows in the Victoria Land coastal ocean region of the Western Ross Sea. Here we use oceanographic data from near to the tongue to explore the interplay between the floating glacier and the local currents and stratification. A vessel-based circuit of the glacier, recording ocean temperature and salinity profiles, reveals the southwest corner to be the coldest and most complex in terms of vertical structure. The southwest corner structure beneath the surface warm, salty layer sustains a block of very cold water extending to 200 m depth. In this same location there was a distinct layer at 370 m not seen anywhere else of water at ~â1.93°C. The new observations broadly, but not directly, support the presence of a coherent Victoria Land Coastal Current. The data suggest the northward moving coastal current turns against the Coriolis force and works its way anticlockwise around the glacier, but with leakage beneath the glacier through the highly 'rippled' underside, resulting in a spatially heterogeneous supply to the Terra Nova Bay Polynya region â an important location for the formation of high-salinity shelf water
The ARGO Project: assessing NA-TECH risks on offshore oil platforms
Abstract Analysis of natural and anthRopoGenic risks on Offshore platforms (ARGO) is a 3-years project, funded by the Italian Ministry of Economic Development. The project, coordinated by AMRA, a permanent Research Centre for the development of innovative technologies applied to environmental problems, aims at providing technical-support for the analysis of natural and anthropogenic risks on offshore oil-platforms. ARGO has developed methodologies for the probabilistic analysis of industrial accidents triggered by natural events (NA-TECH) on offshore platforms. The final analysis of the ARGO Project suggest a constant monitoring of exploitation activity, fluids re-injection and storage using high technology networks
results of the first wave glider experiment in the southern tyrrhenian sea
A wave-propelled autonomous vehicle (Wave Glider) instrumented with a variety of oceanographic and meteorological sensors was launched from Gulf of Naples on the 12th of September 2012 for a two-week mission in the Southern Tyrrhenian Sea. The main objective of the mission was a preliminary evaluation of the potential of commercial autonomous platforms to provide reliable measurements of sea surface parameters which can complement existing satellite based products moving from the local to the synoptic scale. To this aim Wave Glider measurements were compared to equivalent, or near-equivalent, satellite products achieved from MODIS (Moderate Resolution Imaging Spectroradiometer) sensors onboard the EOS (Earth Observing System) satellite platforms and from AVISO (Archiving Validation and Interpretation of Satellite Oceanographic Data). Level-3 near real time and Level-4 reprocessed sea surface foundation temperature products provided by the CMEMS (Copernicus Marine Environment Monitoring Service) were also included in this study as well as high resolution model output supplied by NEMO (Nucleus for European Modelling of the Ocean). The Wave Glider was equipped with sensors to measure temperature, salinity, currents, as well as Colored Dissolved Organic Matter (CDOM), turbidity and refined fuels fluorescence. The achieved results confirmed the emerging value of Wave Gliders in the framework of multiplatform monitoring systems of the ocean surface parameters. In particular, they showed that Wave Glider measurements captured the southern Tyrrhenian Sea major surface oceanographic features, including the coast to open sea haline gradient and the presence of a cyclone-anticyclone system in the southeastern sub-region. The Wave Glider also had the capability to monitor upper ocean currents at finer spatial and temporal scales than satellite altimetric observations and model outputs. Nonetheless, results stressed the existence of several limits in the combined use of satellite and Wave Glider observations and the necessity of further analyses concerning the monitoring of the ocean optical properties. In fact, Wave Glider and satellite-based products agree in terms of sea surface temperature and currents patterns, while bio-optical properties turned out to be less well correlated. No significant traces of refined fuels have been detected along the WG track.</p
A New Orbiting Deployable System for Small Satellite Observations for Ecology and Earth Observation
In this paper, we present several study cases focused on marine, oceanographic, and
atmospheric environments, which would greatly benefit from the use of a deployable system for
small satellite observations. As opposed to the large standard ones, small satellites have become an
effective and affordable alternative access to space, owing to their lower costs, innovative design
and technology, and higher revisiting times, when launched in a constellation configuration. One
of the biggest challenges is created by the small satellite instrumentation working in the visible
(VIS), infrared (IR), and microwave (MW) spectral ranges, for which the resolution of the acquired
data depends on the physical dimension of the telescope and the antenna collecting the signal. In
this respect, a deployable payload, fitting the limited size and mass imposed by the small satellite
architecture, once unfolded in space, can reach performances similar to those of larger satellites.
In this study, we show how ecology and Earth Observations can benefit from data acquired by
small satellites, and how they can be further improved thanks to deployable payloads. We focus on
DORAâDeployable Optics for Remote sensing Applicationsâin the VIS to TIR spectral range, and
on a planned application in the MW spectral range, and we carry out a radiometric analysis to verify
its performances for Earth Observation studies
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