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Initiated by the SCAR scientific research programme “Antarctic Thresholds – Ecosystem Resilience and Adaptation” (AnT-ERA, 2013-2021), 26 experts synthesized knowledge on impacts and risks of climate-change on biological processes and ecosystem functions in the Antarctic. The ten main scientific messages that emerged addressed (1) accelerating marine and terrestrial biogeochemical cycles, (2) response to ocean acidification, (3) ecological changes in climate change hot spots, (4) unexpected dynamism of marine seafloor communities, (5) biodiversity shifts, (6) low temperature limitation of protein synthesis, (7) life intrinsically linked to changing sea ice conditions, (8) pollution, (9) genetically distinct terrestrial populations under threat, and (10) newly discovered habitats. Two-thirds of the literature included in this synthesis was published between 2010 and 2020 and only one-third was published earlier. The fast mounting, recent decadal evidence indicates various Antarctic biological communities now experience climate stress, or will experience such stress in the coming decades. The responses of organisms, ecosystem functions and services to environmental changes are complex and varied. Key knowledge gaps remain and need addressing to adequately assess future prospects for life in the Antarctic.

The mid-Tyrrhenian coast is the most complex volcano-tectonic sector in the Mediterranean basin. Here the vertical ground movements (VGMs) due to the interaction between extensive tectonic processes and volcano-tectonic activities have a significant impact on both past and future sea-level evolution. This area represents the youngest basin of the western Mediterranean and it hosts one of the most active volcanic districts, formed by the Campi Flegrei and Vesuvius volcanoes, which are worldwide known for the vertical ground movements accompanying their volcanic activity since the https://dist.altervista.org/seaproxy/ ). This includes newly produced sea-level data from recent marine surveys, which were coupled to previously available data standardized according to the recent international guidelines for RSL studies. This allowed producing a multiproxy dataset composed of depositional, erosional, biological, and archaeological sea-level markers, in this very complex Mediterranean area. The collected sea-level data were further

The timing, duration and evolution of sea level during the Marine Isotope Stage 5e (MIS 5e) highstand is a subject of intense debate. A major problem in resolving this debate is the difficulty of chronologically constraining the sea level fall that followed the peak of the highstand. This was mainly controlled by ice-sheet dynamics, the understanding of which is relevant for assessing future sea-level behavior due to global warming. Here we use stratigraphical and geochoronological (U/Th dating and tephra fingerprinting) evidence from the Infreschi archaeological cave (Marina di Camerota, Southern Italy) to constrain relative sea level (RSL) evolution during the MIS 5e highstand and younger stages. Uranium-thorium dating of speleothem deposition phases places the maximum highstand RSL at 8.90 ± 0.6m a.s.l., as indicated by the near-horizontal upper limit of Lithophaga boreholes measured for along a ∼3.5 km coastal cliff section. Geochronological data show that RSL fell more than 6 m before ∼120 ka, suggesting a duration of the Last Interglacial highstand significantly shorter than proposed in some previous studies. Modelling shows that the RSL trend predicted by the ICE-5G and ICE-6G ice-sheet simulations is consistent with our data, but requires an additional significant reduction of both Greenland and Antarctic ice sheets to match the height of the local maximum highstand if no correction for tectonics is applied. Reconciling field data and models requires an earlier and likely shorter duration of the MIS 5e highstand. This suggests that our new data can constrain global ice-volume variations during the penultimate deglaciation, as well as glacial inception at the end of the Last Interglacial. According to our chronology, there is no local evidence of higher-than-present-day sea levels after 120 ka.

We produced a new suite of sea-level data which allowed assessing the Holocene evolution of the Bonifacio Strait, a key coastal sector of the Mediterranean Sea which experienced significant morphological changes since the Last Glacial Maximum. Squeezed between Corsica and Sardinia islands, this strait connects the two major basins of the western Mediterranean. Due to its peculiar geographic and morphological setting, the Bonifacio Strait is affected by extreme meteomarine conditions characterized by severe winds, waves, and currents.The millennial sea-level changes were reconstructed through multiproxy investigations made of sediment coring and underwater beachrock sampling carried out on both sides of the strait. These data provided fresh insights into the timing of the progressive opening of the Bonifacio Strait which followed the Last Glacial Maximum when Corsica and Sardinia were connected forming the largest Mediterranean island. Major palaeogeographic changes occurred before ~7 ka BP. Since that period, the significant decrease of the northern ice-sheet melting triggered a significant sea-level stabilization which induced only minor modifications in the palaeogeography of the strait. In the late Holocene, the isostatic-related subsidence became the dominant factor controlling the sea-level changes which rose with rates ≤0.35 mm a−1 in the last four millennia.Our data have also an important archaeological implication because they indicate that the Bonifacio Strait has not represented a significant geographical barrier along the early Neolithic migration path which connected mainland Italy to northern Corsica and finally to Sardinia. This further confirms the ability of early Neolithic communities to navigate not also across large sea stretches but also maritime areas characterized by extremely complex meteomarine conditions.

We assembled a database of Holocene relative sea-level index points (n = 213) and marine (n = 211) and terrestrial (n = 122) limiting points for the broader South and Southeast Asian region including the Maldives, India and Sri Lanka. The standardized review of published age-elevation information from corals, deltaic, estuarine and mangrove deposits, beachrocks and tidal notches, yielded a new suite of relative sea-level index and limiting points produced according to a standardized protocol. Expected spatial variability in Holocene relative sea-level change due to glacial isostatic adjustment was accounted for, by first subdividing the study area into ten geographic sub-regions from the Central Indian Ocean to the Western Tropical Pacific, and second by comparing sub-regional relative sea-level data to model predictions of glacial isostatic adjustment. Results show that some of the regionally constrained relative sea-level data are characterized by significant inconsistencies that cannot be explained by glacial isostatic adjustment. Such inconsistencies of standardized relative sea-level data become particularly obvious in areas around the Red River Delta in Vietnam, the Gulf of Thailand, the northwest coast of Malaysia and the Spermonde Archipelago in Indonesia. Based on a critical evaluation of the reviewed relative sea-level indicators, we discuss possible sources of local divergence and identify regions where data are currently insufficient to constrain glacial isostatic adjustment predictions. The remaining quality-controlled and consistent relative sea-level data show that glacial isostatic adjustment and syn-/post-formational influences such as tectonic uplift, subsidence and compaction were the dominant local drivers of Holocene relative sea-level change. Collectively, the results of this review suggest that Holocene sea levels in South and Southeast Asia and surrounding regions have been controlled by a variety of global and local drivers and imply that ad