Sea-level changes in the Adriatic from tide-gauge data Fabio RaicichAssessing the impact of climate change in Italian coastal areas: tools and methods of risk and vulnerability assessment. Silvia Torresan, Elisa Furlan, Petra dalla Pozza, Diana Derepasko, Andrea Critto, Melania Michetti, Mattia Amadio, Jaroslav Mysiak 35131, Padova, Italy alessandro.fontana@unipd.it, livio.ronchi@gmail.com ANNAMARIA CORREGGIARI CNR-ISMAR Institute of Marine Sciences in BolognaVia Gobetti 101, 40129, Bologna, Italy anna.correggiari@bo.ismar.cnr.it STEFANO FURLANIUniversity of 34128, Trieste, Italy Stefano.furlani@units.it MLADEN JURAČIĆ, IGOR FELJAUniversity of Zagreb -Faculty of Science, Department of Geology Horvatovac 102a, 10000, Zagreb, Croatia mjuracic@geol.pmf.hr, igorfelja@geol.pmf.hr In the last years strong e orts have been done by the scienti c community to reconstruct the post-LGM transgression and describe it through geophysical models that could match with the observed eld data. Notwithstanding, the eustatic curve is still largely unconstrained before 8 ka BP because of the few available data. Northern Adriatic is one of the very few places in the Mediterranean Basin where the sea-level variations occurred between Lateglacial and Early Holocene are recorded. These changes are documented by sediments and landforms, thanks to the gentle slope of the continental shelf and the occurrence of lagoon and paralic environments, which are strongly sensitive even to subtle variations of the sea level. This research considered the large database of CHIRP-Sonar pro les and stratigraphic cores collected by CNR-ISMAR of Bologna, especially through the oceanographic missions carried out on-board of the research vessel Urania. A major issue is the recognition and characterization of the periods of rapid increase of the sea level, which punctuated some phases during the Lateglacial and the rst part of Holocene, which caused the abrupt submersion of large sectors of the coast. In the study area the remnants of a large barrier-island system formed during Younger Dryas and drowned in place soon after are present. Moreover, important information about a sea-level jump occurred around 9.5-9.2 ka BP have been recently documented in the deltaic plain of Po River and in the submerged shelf. This phase of transgression led the Adriatic to enter in the Gulf of Trieste, dramatically transforming the area between Istria and the coast of Friuli. Some key questions, still partly unsolved, are related to the main indexes allowing the identi cations of sea-level jumps and the possible occurrence of sea-level stillstands or the apparent decrease of the marine rise because of the increase in sediment supply.Keywords: transgressive deposits, lagoon environments, submarine landforms We investigated MIS 5.5 fossil tidal notches located in tectonically stable coasts of the central Mediterranean. In these stable areas, the elevation of the base of the MIS 5.5 notch ranges from 2.09 to 12.48 m, with a mean of 5.7 m. Such variability,...

Aims. We investigate the oscillatory properties of the quiet solar chromosphere in relation to the underlying photosphere, with particular regard to the effects of the magnetic topology. Methods. For the first time we perform a Fourier analysis on a sequence of line-of-sight velocities measured simultaneously in a photospheric (Fe I 709.0 nm) and a chromospheric line (Ca II 854.2 nm). The velocities were obtained from full spectroscopic data acquired at high spatial resolution with the Interferometric BIdimensional Spectrometer (IBIS). The field of view encompasses a full supergranular cell, allowing us to discriminate between areas with different magnetic characteristics. Results. We show that waves with frequencies above the acoustic cut-off propagate from the photosphere to upper layers only in restricted areas of the quiet Sun. A large fraction of the quiet chromosphere is in fact occupied by "magnetic shadows", surrounding network regions, that we identify as originating from fibril-like structures observed in the core intensity of the Ca II line. We show that a large fraction of the chromospheric acoustic power at frequencies below the acoustic cut-off, residing in the proximity of the magnetic network elements, directly propagates from the underlying photosphere. This supports recent results arguing that network magnetic elements can channel low-frequency photospheric oscillations into the chromosphere, thus providing a way to input mechanical energy in the upper layers.

On the basis of observations of solar granulation obtained with the New Solar Telescope (NST) of Big Bear Solar Observatory, we explored proper motion of bright points (BPs) in a quiet sun area, a coronal hole, and an active region plage. We automatically detected and traced bright points (BPs) and derived their mean-squared displacements as a function of time (starting from the appearance of each BP) for all available time intervals. In all three magnetic environments, we found the presence of a super-diffusion regime, which is the most pronounced inside the time interval of 10-300 seconds. Super-diffusion, measured via the spectral index, γ, which is the slope of the mean-squared displacement spectrum, increases from the plage area (γ = 1.48) to the quiet sun area (γ = 1.53) to the coronal hole (γ = 1.67). We also found that the coefficient of turbulent diffusion changes in direct proportion to both temporal and spatial scales. For the minimum spatial scale (22 km) and minimum time scale (10 sec), it is 22 and 19 km 2 s −1 for the coronal hole and the quiet sun area, respectively, whereas for the plage area it is about 12 km 2 s −1 for the minimum time scale of 15 seconds. We applied our BP tracking code to 3D MHD model data of solar convection (Stein et al. 2007) and found the super-diffusion with γ = 1.45. An expression for the turbulent diffusion coefficient as a function of scales and γ is obtained.

Context. The chromosphere remains a poorly understood part of the solar atmosphere, as current modeling and observing capabilities are still ill-suited to investigate in depth its fully 3-dimensional nature. In particular, chromospheric observations that can preserve high spatial and temporal resolution while providing spectral information over extended fields of view are still very scarce. Aims. In this paper, we seek to establish the suitability of imaging spectroscopy performed in the Ca II 854.2 nm line as a means to investigate the solar chromosphere at high resolution. Methods. We utilize monochromatic images obtained with the Interferometric BIdimensional Spectrometer (IBIS) at multiple wavelengths within the Ca II 854.2 nm line and over several quiet areas. We analyze both the morphological properties derived from narrow-band monochromatic images and the average spectral properties of distinct solar features such as network points, internetwork areas and fibrils. Results. The spectral properties derived over quiet-Sun targets are in full agreement with earlier results obtained with fixed-slit spectrographic observations, highlighting the reliability of the spectral information obtained with IBIS. Furthermore, the very narrowband IBIS imaging reveals with much clarity the dual nature of the Ca II 854.2 nm line: its outer wings gradually sample the solar photosphere, while the core is a purely chromospheric indicator. The latter displays a wealth of fine structures including bright points, akin to the Ca II H 2V and K 2V grains, as well as fibrils originating from even the smallest magnetic elements. The fibrils occupy a large fraction of the observed field of view even in the quiet regions, and clearly outline atmospheric volumes with different dynamical properties, strongly dependent on the local magnetic topology. This highlights the fact that 1-D models stratified along the vertical direction can provide only a very limited representation of the actual chromospheric physics. Conclusions. Imaging spectroscopy in the Ca II 854.2 nm line currently represents one of the best observational tools to investigate the highly structured and highly dynamical chromospheric environment. A high performance instrument such as IBIS is crucial in order to achieve the necessary spectral purity and stability, spatial resolution, and temporal cadence.

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