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The drill of the EPICA Dome C ice core has been completed almost 20 years ago. This ice core already provided many reference records for climate and atmospheric greenhouse gase concentrations over the last 800,000 years, hence covering 9 glacial interglacial transitions or glacial terminations. These records combined to records from other archives have already shown the diversity in term of amplitudes and durations of the last 9 glacial terminations occurring in different orbital contexts. Still, the relatively low resolution of the current records hampered a good chronology of the oldest deglaciations as well as the study of the rapid climatic variability at centennial to multi-millennial scale superimposed to the longer term orbital climatic variability.Here, we will present high resolution measurements of water and air isotopes on the EPICA Dome C ice core over the last 800,000 years with a particular focus on glacial terminations. These new data enable to improve the chronology of the EPICA Dome C ice core hence improving the link between orbital forcing and climatic variability, especially for the period between 800,000 years and 200,000 years before present. In addition, our relatively high resolution records (50-300 years) of water and air isotopes enable us to describe on the same chronology the occurrence of millennial scale variability in the low to mid latitudes over the terminations 2, 3, 4 and 5 (occurring between 440,000 and 120,000 years before present) while local climate at the drilling site of EPICA Dome C has a much smoother evolution. &nbsp, The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Ice cores from inner East Antarctica provided some of the longest and most detailed climatic reconstructions and allowed understanding the relationships between atmospheric mineral dust and climate. In this work we present synchrotron radiation X-ray Fluorescence geochemical data of dust from the TALDICE ice core drilled at Talos Dome, a peripheral ice dome of East Antarctica (Western Ross Sea). Results highlight a dominant southern South American origin for dust at TALDICE during the Last Glacial Maximum, similarly to other sites located further inland onto the polar plateau. On the contrary, a different scenario concerns Talos Dome during the Holocene if it is compared to more inner sites. The tight connection between high southern latitudes and Antarctica that characterizes cold climate stages becomes weaker since the onset of the last climatic transition and throughout the Holocene. The net effect of this process at Talos Dome is a modification of the atmospheric and environmental settings, owing to local Antarctic sources of Victoria Land to gain importance and become the dominant ones. At the same time in inner East Antarctica the provenance of dust remains remote also during Holocene, revealing an evolution of the homogeneous scenario observed in glacial periods. The enhanced sensitivity of peripheral ice sheet sites to local dust sources makes Talos Dome an ideal site to assess the climatic and atmospheric changes of the peripheral sectors of East Antarctica during the current interglacial period.Plain Language Summary During the Last Glacial Maximum, about 20,000 years ago, mineral dust from South America was massively transported toward Antarctica as a consequence of impressive environmental and climatic changes. Many ice cores drilled from the inner sectors of the Antarctic ice sheets support this scenario. Little is known when attention is shifted to peripheral areas and to interglacial periods. A new record of mineral particles at Talos Dome, a peripheral area of the East Antarctic ice sheet (Western Ross Sea sector), is here presented to partially close these gaps. Combining the data about concentration, composition, and grain size of the dust deposited at Talos Dome, it was possible to appreciate the influence played by local Antarctic dust sources to the depositional budget of the site. These local sources, corresponding to localized ice-free areas, are extremely important when attention is given to the peripheries of the ice sheets. This is particularly true for interglacial periods, when the transport and the deposition of mineral dust from South America to Antarctica is much reduced.

Questo Rapporto tecnico rappresenta la sintesi dei contributi (abstract) presentati al primo incontro del Gruppo di Lavoro Dinamica del Paleoclima del CNR che si è svolto a Bologna nella sede del CNR dal 17-18 Giugno 2019. Questo incontro ha avuto come focus la storia e la dinamica del clima durante gli ultimi 150 mila anni: dalla penultima glaciazione del MIS 6 attraverso l'ultimo interglaciale, le oscillazioni rapide che scandiscono l'ultima glaciazione, le culminazioni dell'Ultimo Massimo Glaciale e la transizione climatica al presente interglaciale. Di estrema rilevanza sono gli eventi che caratterizzano l'Olocene fino alla storia più recente degli ultimi 2000 anni, che forniscono la prospettiva a lungo termine degli studi sul cambiamento in atto. La sincronizzazione e teleconnessione degli effetti del cambiamento climatico negli ambienti marini e continentali; le oscillazioni del livello del mare e le stime di temperatura utilizzando la vasta gamma di proxies marini e continentali (dai sedimenti marini agli speleotemi, varve, carote di ghiaccio e piante) sono di speciale interesse a tutte le scale geografiche.

Understanding the causes of recent climatic trends and variability in the high-latitude Southern Hemisphere is hampered by a short instrumental record. Here, we analyse recent atmosphere, surface ocean and sea-ice observations in this region and assess their trends in the context of palaeoclimate records and climate model simulations. Over the 36-year satellite era, significant linear trends in annual mean sea-ice extent, surface temperature and sea-level pressure are superimposed on large interannual to decadal variability. However, most observed trends are not unusual when compared with Antarctic paleoclimate records of the past two centuries. With the exception of the positive trend in the Southern Annular Mode, climate model simulations that include anthropogenic forcing are not compatible with the observed trends. This suggests that natural variability likely overwhelms the forced response in the observations, but the models may not fully represent this natural variability or may overestimate the magnitude of the forced response.

The final conclusions of a multidisciplinary study of Earth and Soil Sciences, carried out in the frame of Prin 2007 are presented. The study has dealt with a variety of natural materials, encompassing soils, waters, atmospheric depositions, the vegetation and the bottom sediments of a coastal lagoon, in the territory north of Ravenna, characterized by important agricultural and industrial activities. In particular, by chemical and isotopic methodologies and pedological survey, it has been studied the ecosystem of the San Vitale Pinewood and the Lagoon of Pialassa Baiona, both constituting the southernmost part of the Po river delta Park. The results obtained have shown that the Pinewood is affected by major salinization processes induced by local subsidence and concerning underground water and soils. This jeopardizes the vegetation's health, in particular, the pine trees that are the main characteristic species. Moreover, the proximity of the industrial zone of Ravenna to the Pinewood represents another threat to the environment, as it is a major pollution source by release of particulate matter with stacks. Therefore, potentially toxic elements may fallout onto the soils, waters and vegetation of the Pinewood, arising general concern on the preservation of the forest. The important traffic rolling on the road net contouring the Pinewood-Lagoon ecosystem is a further source of pollution, as indicated by the incoming diffusion of PGE on the topsoils bordering the roads. Lastly, the study of the bottom deposits of the Lagoon at the water-sediment interface has unveiled the diffuse presence of Hg with significant concentrations, derived from industrial wastewaters unloaded in the basin some decades ago. Luckily, Hg occurs in the element form and, thus, its mobility is very reduced, keeping so far the risk factor in the Lagoon low. As a whole, the Pinewood-Lagoon ecosystem is ailing due to incoming salinization processes and, subordinately, moderate pollution proceeding from the industrial zone and the traffic. Therefore, it is recommended to implement a monitoring survey of the study area on the ground of the parameters used in this research. In fact, they have been able to provide the local Administrations with punctual responses to the problem of degradation of the Pinewood-Lagoon ecosystem.

Glaciological and climatological studies in ice-caves of Moncodeno (North Grigna, Province of Lecco, Lombardy). The existence of perennial ice and snow deposits in the karst shafts of the Moncodeno area, at altitudes of about 1800 to 2100 m a.s.1, has long been known. Even so, no detailed study has been formerly carried out. Three ice and snow cores have been drilled in the glaciated cave environment and chemical, isotopical, crystallographical and textural analysis were carried out on them. By linking these observations with the morphology, stratigraphy and internal structures of the deposits, and with the hypogean and epigean climatological records, we were able to identify the accumulation processes and to give one upper and some lower limits to the age of these deposits. The most notable deposit shows a more than 15 m thick succession of clear-ice layers, found at a depth of about 80 m and suspended between two shafts in the cave "Abisso sul margine dell'Alto Bregai". Because of the relative position to the cave entrance, no snow can reach this deposit. The crystallographic and textural features, confirmed by the chemical and isotopical trends, show that this is lake-ice. At present no accumulation can be observed and the top surface is now at least 3 m lower than it was three decades ago. The underlying shaft, deglaciated at some time in the past by the air circulation, drains the water so that hypogean lakes can no more develop. We have found sound stratigraphie and glaciotectonic evidences of at least three accumulation and three ablation phases. When compared to local present precipitations and to the values available from literature , the ice chemical composition and δ180 values show that this ice must be younger than the end of the last ice age, while preceding the beginning of industrial activity related contributions, Studi glaciologici e clima tologici in alcune grotte Ghiacciaie in Moncodeno (Grigna settentrionale, Lecco, Lombardia). La presenza di depositi perenni di ghiaccio e di nevato nei pozzi carsici del Moncodeno, a quote comprese tra 1800 e 2100 m circa, è nota da tempo. Non esistono tuttavia precedenti hvori dettagliati. Lo studio chimico, isotopico, cristallograjïco e tessiturale su tre carote di ghiaccio e nevato estratte in ambiente ipogeo, integrato con i risultati dello studio morfologico, stratigrafico e strutturale dei depositi, e con i dati di climatologia ipogea ed epigea, hafornito le modalite di accumulo e indicato un limite massimo e alcuni limiti minimi all'età dei depositi. Di particolare interesse è un deposito di ghiaccio trasparente stratificato che si trova alla profondità di circa 80 m, spesso piit di 10 m, sospeso tra due pozzi nella grotta "Abisso sul margine dell' Alto Bregai " e in posizione tale da escludere un'alimentazione nevosa. Le caratteristiche cristallografiche e tessiturali, in accordo con i trend chimici e isotopki, indicano che il deposito è formato da strati di ghiaccio di lago. Attualmente non si osservano periodi di accumulo e la superficie si è abbassata di almeno 3 metri nel corso degli ultimi tre decenni. Il pozzo sottostante al deposito, deglaciato dalla circolazione d'aria, drena le acque impedendo oggi la formazione di nuovi laghi ipogei. I rilievi stratigrafici e glaciotettonici permettono di riconoscere con certezza almeno tre fasi di accumulo e tre fasi di ablazione. La composizione chimica e il rapporto isotopico dell'ossigeno nel ghiaccio, confrontati con i valori dette precipitazioni locali attuali e con quelli presenti in letteratura, indicano con certezza un'età più recente delta fine dell'ultima era glaciale e precedente all'inizio di un sensibile apporto legato all'attività industriale., La présence de neige et de glaces pérennes dans les gouffres du Moncodeno est connue depuis longtemps, et pourtant aucune étude détaillée ne leur a jusqu'ici été consacrée. Trois carottes de neige et de glace ont été prélevées dans ces cavités, et des analyses chimiques, isotopiques, cristallographiques ont été menées, ainsi que des études sur leur texture. En croisant ces observations avec les données morphologiques, stratigraphiques et structurelles des accumulations nivo-glaciaires, et avec les enregistrements climatologiques en surface et sous terre, il a été possible de caractériser les processus d'accumulation et de fournir une fourchette (une limite haute et plusieurs limites basses) sur l'âge de ces dépôts. L'échantillon le plus intéressant, prélevé à environ 80 m de profondeur entre deux puits du gouffre "sul margine dell'Alto Bregai" montre, sur plus de 15 m d'épaisseur, une succession de strates de glace transparente. La situation de ce glacier suspendu, éloigné de l'orifice, fait que les chutes de neige ne peuvent l'alimenter. La texture et la cristallographie, associées aux données chimiques et isotopiques, indiquent qu'il s'agit là d'une glace de lac. Mais on n'observe plus aujourd'hui d'accumulation, et le niveau de la glace a baissé d'au moins trois mètres en 30 ans. Le puits sous-jacent, parfois déglacé dans le passé sous l'action des circulations d'air, draine les eaux de fonte si bien que le lac souterrain ne peut plus se former. L'étude de la stratigraphie et de la glacio-tectonique démontre l'existence d'au minimum trois cycles d'accumulation et d'ablation. Si on les compare aux précipitations locales actuelles et aux évolutions publiées dans la littérature, la composition chimique de la glace et les valeurs du δ180 montrent que cette glace doit être postérieure à la dernière période glaciaire mais a dû précéder les débuts de l'activité industrielle., Turri S., Citterio M., Bini Alfredo, Maggi V., Udisti R., Stenni B., Gauchon-Alabeatrix Catherine. Etude glaciologique et climatologique des cavités glacées du Moncodeno (Grigna septentrionale, province de Lecco, Lombardie). In: Karstologia : revue de karstologie et de spéléologie physique, n°42, 2e semestre 2003. Les cavités glaciaires sous le regard des spéléologues. pp. 37-44.