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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,...

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Earth's climate has oscillated between short-lived interglacial and extended glacial periods for the past million years. Before the last interglacial, absolutely dated markers of sea level become increasingly rare; hence, our knowledge of sea-level change driven by the waxing and waning of continental ice sheets before that time is largely based on proxy records from deep-sea cores [1][2][3] that lack direct age control. Here we present precise U-Th ages for a remarkable collection of submerged speleothems 4,5 from Italy, which record three sealevel highstands during the penultimate interglacial period, Marine Isotope Stage 7, from 245,000 to 190,000 years ago. We find that sea level rose above −18 m (relative to modern sea level) several thousand years before maximum Northern Hemisphere insolation during the first and third highstands. In contrast, the second highstand, Marine Isotope Stage 7.3, is essentially synchronous with the insolation maximum, and sea level during this highstand only peaked at about −18 m, even though the concurrent insolation forcing was the strongest of the three highstands. We attribute the different phasing and amplitude of the Marine Isotope Stage 7.3 highstand to the extensive continental glaciation that preceded it. This finding highlights the significance of cryosphere response time to the climate system.Reconstructions of previous interglacial periods can help elucidate the phasing and causal mechanisms linking temperature, sea level and greenhouse-gas concentrations that are critical to our understanding of climate dynamics during the present interglacial and into the future. Although the penultimate interglacial offers an important test for theories about the timing, duration, magnitude and driving mechanisms of sea-level highstands that have evolved out of studies of the last interglacial and the Holocene, fewer data are available for this period of time. Hence, the additional data presented herein provide an important test for several competing reconstructions of sea level during Marine Isotope Stage (MIS) 7 (refs 2, 3, 6-8) (Fig. 1).A common approach to reconstruct past sea level is to measure the age and elevation of geological archives that formed at a known position relative to the sea surface, such as corals 7 that grow in shallow water, or speleothems 9,10 that grow in caves and serve as an upper limit to sea-level elevation. The strength of this method lies in the degree of confidence afforded by an accurate and precise chronology, such as provided by the U-Th dating technique, and in the ability to precisely measure the elevation relative to present sea level. We have applied this technique to submerged speleothems recovered from Argentarola Cave, Italy, that preserve alternating layers of spelean calcite that grew when the caves were above sea level and biogenic calcite secreted by serpulid worms that colonized the speleothems during sea water submergence 4 . One of the advantages of the speleothem archive relative to corals is that dense spelean calcite is less sus...