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Glacial extent and mass balance are sensitive climate proxies providing solid information on past climatic conditions. However, series of annual mass-balance measurements of more than 60 years are scarce. To our knowledge, this is the first time the latewood density data (MXD) of the Swiss stone pine (Pinus cembra L.) have been used to reconstruct the summer mass balance (Bs) of an Alpine glacier. The MXD-based Bs well correlates with a Bs reconstruction based on the May to September temperature. Winter precipitation has been used as an independent proxy to infer the winter mass balance and to obtain an annual mass-balance (Bn) estimate dating back to the glaciological year 1811/12. The reconstructed MXD/precipitation-based Bn well correlates with the data both of the Careser and of other Alpine glaciers measured by the glaciological method. A number of critical issues should be considered in both proxies, including non-linear response of glacial mass balance to temperature, bedrock topography, ice thinning and fragmentation, MXD acquisition and standardization methods, and finally the ‘divergence problem’ responsible for the recently reduced sensitivity of the dendrochronological data. Nevertheless, our results highlight the possibility of performing MXD-based dendroglaciological reconstructions using this stable and reliable proxy.

Many surgical approaches have been described for hip hemiarthroplasty (HHA) treating femur neck fractures (FNFs). Direct lateral approach (DLA) is one of the most used. Today, the direct anterior approach (DAA) has become very attractive, but it seems to involve more intra-operative fractures. Our main endpoint was to demonstrate that the DAA may be a valid alternative comparing to the DLA.Patients affected by FNFs and treated with HHA between the years 2016 and 2020 were studied. We divided the treatment of the fractures according to the surgical approach. The analysis was focused on perioperative complications and radiological outcomes.There were a total of 166 patients. The DLA group included patients with an average age of 83.5 years and the DAA group of 83 years. We found similar surgical times (DLA 67 min vs DAA 61 min; p = 0,55), number of transfusions (DLA 3/person vs DAA 4/person; p = 0,91), perioperative complications (fractures: DLA 0 vs DAA 0 - dislocations: DLA 2,50% vs DAA 0) and functional outcomes (HHS: DLA 83 points vs DAA 87 points; p = 0,71). There were no statistical differences comparing diaphyseal filling (Canal Fill Index at the proximal third: DLA 0,79 vs DAA 0,78; p= 0,24), bone loss (Paprosky I: DLA 96,25% vs DAA 91,86%; p = 0,47) and prevalence of heterotopic ossification (Broker low degree: DLA 93,75% vs 95, 34%; p = 0,87).Analysing perioperative complications and studying post-operative radiographic evolution, our results suggest that the DAA is a valid alternative to the DLA in HHA treating FNFs.

The temperature rise at the global level and glacier shrinkage are deemed to induce new dynamics between biotic and abiotic factors, especially in mountain regions. In this work, we aimed to assess: (a) the area made available after glacier retreat since the Little Ice Age (LIA) for the colonization of alpine plants; (b) the ability of 14 alpine and nival species, typically growing on peaks and in deglaciated areas, to migrate and survive at lower elevations in microrefugia across the treeline ecotone. In the Adamello-Presanella Massif (Rhaetian Alps), we collected presence data on 14 alpine species within 3 × 3 or 5 × 5 m plots according to slope landforms and deposits. The analysis of the elevation range of the investigated species across the treeline was performed using Sentinel-2 satellite images to derive the actual position of the upper and lower treeline. The differences in the species elevation ranges across slope landforms, in relation to the treeline elevation and aspect, were detected with linear mixed models. Results showed that glaciers contracted sharply by more than 50% between the LIA and 2006, making large deglaciated areas available (more than 57 km2). All the studied species were found at low altitudes across the treeline ecotone, from about 500 to 1200 m below their typical habitat. Six species (Cardamine resedifolia, Cerastium uniflorum, Leucanthemopsis alpina, Luzula alpinopilosa, Oxyria digyna, Saxifraga oppositifolia) significantly exceeded the upper treeline in correspondence of alpine composite channels (p < 0.001 for all species). One species (Adenostyles leucophylla) exceeded the upper treeline in correspondence of composite slope deposits (p < 0.05). Two species (Ranunculus glacialis and S. oppositifolia) reached the lower treeline in composite channels and slope deposits (p = 0.800, and p = 0.519, respectively). The retreat of the alpine glaciers, coupled with the intensification of paraglacial processes, may favor new habitat opportunities at high elevation and microrefugia at low altitudes for nival and alpine species. The widespread presence of microrefugia for alpine plants downslope during warm periods suggests a low incidence of biodiversity loss in the alpine regions due to climate change.

As a result of climate changes, penguins are predicted to be at risk of losing their breeding habitats. Changes in penguin colony distribution suggest that some colonies have withstood environmental changes better than others, serving as initial post-glacial settlements or refuges in adverse climatic conditions. Here we have synthesized over 200 dates (including 91 new dates) of penguin remains and of guano in 107 ornithogenic profiles from abandoned nests on Inexpressible Island, one of the longest persisting Adélie penguin colonies in Antarctica, to investigate the dynamics of population size and the role of this island in the ecological history of this species. The results indicate that, following the retreat of Ross Ice Shelf, the Adélies first colonized this island at ~8.6 kyr BP, documenting the earliest known breeding site in the Ross Sea since deglaciation. During ~7-3 kyr BP the reconstructed population on Inexpressible Island was generally consistent with the change in pack ice, reaching relative peaks at 5.5-5.0 and 4.0-3.5 kyr BP. After brief decline at 3.5-3.0 kyr, substantial enlargement of the penguin colony occurred between 3.0 and 1.5 kyr BP, attributed to the immigration from the abandoned colonies along the Scott Coast. During this time, the persistent efficiency of Terra Nova Bay polynya offered conditions favourable to the expansion of the penguin population on Inexpressible Island, which probably represented a refuge area under increased coastal sea-ice. This longest-dwelling penguin colony may provide a valuable refuge for the Adélie penguin if the recurrent Terra Nova Bay polynya persists under future climatic and environmental changes, as occurred in the past.

International audience; In this paper, we provide a comprehensive overview of the state-of-knowledge of dust flux and variability in time and space in different sectors of East Antarctica during the Holocene. By integrating the literature data with new evidences, we discuss the dust flux and grain-size variability during the current interglacial and its provenance in the innermost part of the East Antarctic plateau as well as in peripheral regions located close to the Transantarctic Mountains. The local importance of aeolian mineral dust aerosol deflated from low-elevation areas of peripheral East Antarctica is also discussed in the light of new data from several coastal, low-elevation sites.

OBJECTIVE: This article describes the esthetic results in a paradigmatic case of hypomineralized enamel correction on both anterior and posterior teeth to establish a minimal intervention protocol for similar cases. Clinical considerations: The subject was initially provided with casein-calcium-phosphate mineral supplementation. Unpublished laboratory images collected as part of a previously published study depict the results of initial calcium-phosphate supplementation on molar incisor hypomineralization (MIH) molar enamel morphology and indicate that this procedure is mandatory in moderate/severe cases. Prior to defect restoration, in-office bleaching of the anterior segment was conducted with bioactivated Opalescence Boost. Filtek Supreme Ultra Universal Restorative was used as a masking agent, and Filtek A2 enamel was applied as the final layer. CONCLUSION: An 8-year follow-up period is necessary in most moderate/severe MIH cases involving orthodontics and bleaching.

In this paper we present results of the annual glaciological survey (2019) conducted on Italian glaciers. More than 200 volunteers operated in the three Alpine sectors (Piemonte - Valle d'Aosta, Lombardy and Triveneto) and in the Apennines (Calderone Glacier, Gran Sasso Group). Data on the frontal variations measured during the 2019 glaciological survey are reported: 102 glaciers were visited in the Piemonte - Valle d'Aosta sector (54 were measured), 24 in the Lombardy Sector (20 measured), 61 in the Triveneto Sector (54 measured) and 1 in the Apennines. Section on mass balance measurements furnishes data for 21 Italian glaciers monitored during the 2018-2019 hydrological year (4 in the Western Alps, 16 in the Eastern Alps and one in the Central Apennines).

Glacial extent and mass balance are sensitive climate proxies providing solid information on past climatic conditions. However, series of annual mass-balance measurements of more than 60 years are scarce. To our knowledge, this is the first time the latewood density data (MXD) of the Swiss stone pine (Pinus cembra L.) have been used to reconstruct the summer mass balance (B s ) of an Alpine glacier. The MXD-based B s well correlates with a B s reconstruction based on the May to September temperature. Winter precipitation has been used as an independent proxy to infer the winter mass balance and to obtain an annual mass-balance (B n ) estimate dating back to the gla- ciological year 1811/12. The reconstructed MXD/precipitation-based B n well correlates with the data both of the Careser and of other Alpine glaciers measured by the glaciological method. A number of critical issues should be considered in both proxies, including non-linear response of glacial mass balance to temperature, bedrock topography, ice thinning and fragmentation, MXD acquisition and standardization methods, and finally the 'divergence problem' responsible for the recently reduced sensitivity of the dendrochronological data. Nevertheless, our results highlight the possibility of performing MXD-based dendroglaciological reconstructions using this stable and reliable proxy.

In this paper we present results of the annual glaciological survey (2019) conducted on Italian glaciers. More than 200 volunteers operated in the three Alpine sectors (Piemonte - Valle d'Aosta, Lombardy and Triveneto) and in the Apennines (Calderone Glacier, Gran Sasso Group). Data on the frontal variations measured during the 2019 glaciological survey are reported: 102 glaciers were visited in the Piemonte - Valle d'Aosta sector (54 were measured), 24 in the Lombardy Sector (20 measured), 61 in the Triveneto Sector (54 measured) and 1 in the Apennines. Section on mass balance measurements furnishes data for 21 Italian glaciers monitored during the 2018-2019 hydrological year (4 in the Western Alps, 16 in the Eastern Alps and one in the Central Apennines).

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.

BARONI C.,BONDESAN A., CARTURAN L., CHIARLE M., Annual glaciological survey of Italian glaciers (2018). (IT ISSN 0391-9838, 2019).Annual glaciological survey of Italian glaciers is here sum-marized. More than 200 volunteers operated in the three Alpine sectors (Piemonte - Val d'Aosta, Lombardia and Tre Venezie) and in the Apennines (Calderone Glacier, Gran Sasso Group). Data on the frontal variations measured dur-ing the 2018 glaciological survey are reported: 111 glaciers were visited in the Piemonte - Val d'Aosta Sector (60 were measured), 23 in the Lombardy Sector (19 measured), 61 in the Tre Venezie Sector (50 measured) and 1 in the Ap-ennines. Section on mass balance measurements provides data for 20 Italian glaciers monitored during the 2017-2018 hydrological year.

Annual glaciological survey of Italian glaciers is here summarized. More than 200 volunteers operated in the three Alpine sectors (Piemonte - Val d'Aosta, Lombardia and Tre Venezie) and in the Apennines (Calderone Glacier, Gran Sasso Group). Data on the frontal variations measured during the 2018 glaciological survey are reported: 111 glaciers were visited in the Piemonte - Val d'Aosta Sector (60 were measured), 23 in the Lombardy Sector (19 measured), 61 in the Tre Venezie Sector (50 measured) and 1 in the Apennines. Section on mass balance measurements provides data for 20 Italian glaciers monitored during the 2017-2018 hydrological year.

Ongoing climate change strongly affects high-elevation environments in the European Alps, influencing the cryosphere and the biosphere and causing widespread retreat of glaciers and changes in biomes. Nevertheless, high-elevation areas often lack long meteorological series, and global datasets cannot represent local variations well. Thus, proxy data, such as tree rings, provide information on past climatic variations from these remote sites. Although maximum latewood density (MXD) chronologies provide better temperature information than those based on tree-ring width (TRW), MXD series from the European Alps are lacking. To derive high-quality temperature information for the Rhaetian Alps, Pinus cembra L. trees sampled at approximately 2000 m a.s.l. were used to build one MXD chronology spanning from 1647 to 2015. The MXD data were significantly and highly correlated with seasonal May-September mean temperatures. The MXD chronology showed a generally positive trend since the middle of the 19th century, interrupted by short phases of climatic deterioration in the beginning of the 20th century and in the 1970s, conforming with the temperature trends. Our results underline the potential for using Pinus cembra L. MXD to reconstruct mean temperature variations, especially during the onset and latter part of the growing season, providing additional information on parts of the growing season not inferred from TRW. Future studies on MXD for this species will increase the availability of temporal and spatial data, allowing detailed climate reconstructions.

The Late Pleistocene to Holocene transition in the Northern Hemisphere was characterized by abrupt millennial-scale climatic changes testified in the Alpine Chain by proxy records derived from glacial landforms and deposits. A detailed reconstruction of the paleo-glaciers during the deposition of the pre-Little Ice Age (LIA) moraines and newly obtained 10Be exposure ages provide information on the timing of a glacier advance in the Gran Paradiso Group (Western Alps, Italy) related to the regional Egesen stadial as a response to the climatic deterioration at around 12.9–11.7 ka (corresponding to the Younger Dryas in northern Europe and to the Greenland stadial 1 in the INTIMATE event stratigraphy). The study area represents a key site to define the behaviour of the Egesen paleo-glaciers, since they are located in a significant climatic area between the moister Maritime Alps and the Northern Alps. The ELA reconstructions and the comparison with other Alpine sectors provide evidence that current relatively drier conditions in the area postdate the LGM and were already present during the Egesen stadial. Our results support a strong positive YD Arctic Oscillation index, which led to drier conditions in southern Europe and caused negative winter precipitation anomalies., Quaternary Science Reviews, 255, ISSN:0277-3791

A first assessment of the main climatic drivers that modulate the tree-ring width (RW) and maximum latewood density (MXD) along the Italian Peninsula and northeastern Sicily was performed using 27 forest sites, which include conifers (RW and MXD) and broadleaves (only RW). Tree-ring data were compared using the correlation analysis of the monthly and seasonal variables of temperature, precipitation and standardized precipitation index (SPI, used to characterize meteorological droughts) against each species-specific site chronology and against the highly sensitive to climate (HSTC) chronologies (based on selected indexed individual series). We find that climate signals in conifer MXD are stronger and more stable over time than those in conifer and broadleaf RW. In particular, conifer MXD variability is directly influenced by the late summer (August, September) temperature and is inversely influenced by the summer precipitation and droughts (SPI at a timescale of 3 months). The MXD sensitivity to August–September (AS) temperature and to summer drought is mainly driven by the latitudinal gradient of summer precipitation amounts, with sites in the northern Apennines showing stronger climate signals than sites in the south. Conifer RW is influenced by the temperature and drought of the previous summer, whereas broadleaf RW is more influenced by summer precipitation and drought of the current growing season. The reconstruction of the late summer temperatures for the Italian Peninsula for the past 300 years, based on the HSTC chronology of conifer MXD, shows a stable model performance that underlines periods of climatic cooling (and likely also wetter conditions) in 1699, 1740, 1814, 1914 and 1938, and follows well the variability of the instrumental record and of other tree-ring-based reconstructions in the region. Considering a 20-year low-pass-filtered series, the reconstructed temperature record consistently deviates

Upper Pleistocene (MIS 4-2) loess sequences occur in most of continental Europe and in Northern Italy along the Po Plain Loess Basin. Loess is distributed along the flanks of the Po Plain and was deposited on glacial deposits, fluvial terraces, uplifted isolated hills, karst plateaus, slopes and basins of secondary valleys. Loess bodies are generally tiny and affected by pedogenesis, being locally slightly reworked by slope processes and bioturbation. Notwithstanding, loess in the Po Plain is an important archive of paleoenviron-mental record and its mapping provides new insights in paleoenvironmental and palaeoseismic reconstructions of Northern Italy.

This paper concerns the relative sea-level changes associated with the Atlantic Patagonian coast derived from sea-level index points whose elevation was determined by a differential global position system (DGPS). Bio encrustations from outcrops located near Camarones, Chubut, Argentina, consist of autochthonous deposits characterized by Austromegabalanus psittacus (Molina, 1782), encrusting acer vulinid foraminifera, coralline red algae and bryozoans. The association of the different organisms is interpreted as being associated with an intertidal environment, and they have been used as index points to establish the relative sea-level position. The main conclusion is that the relative sea-level between c. 7000 and 5300 cal. yr BP was in the range ofc. 2?4 m a.s.l., with a mean value of c. 3.5 m a.s.l. Our data seem to support the existence of different rates of relative sea-level fall in different sectors of Atlantic Patagonia during the Holocene and highlight the importance of a more precise and accurate relative sea-level estimation by producing new data and revisiting the indicative meaning of most of the indicators so far used in the area., Facultad de Ciencias Naturales y Museo