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Stratigraphic data from salt marshes provide accurate reconstructions of Holocene relative sea-level (RSL) change and necessary constraints to models of glacial isostatic adjustment (GIA), which is the dominant cause of Late-Holocene RSL rise along the U.S. mid-Atlantic coast. Here, we produce a new Mid- to Late-Holocene RSL record from a salt marsh bordering Great Bay in southern New Jersey using basal peats. We use a multi-proxy approach (foraminifera and geochemistry) to identify the indicative meaning of the basal peats and produce sea-level index points (SLIPs) that include a vertical uncertainty for tidal range change and sediment compaction and a temporal uncertainty based on high precision Accelerator Mass Spectrometry radiocarbon dating of salt-marsh plant macrofossils. The 14 basal SLIPs range from 1211 ± 56 years BP to 4414 ± 112 years BP, which we combine with published RSL data from southern New Jersey and use with a spatiotemporal statistical model to show that RSL rose 8.6 m at an average rate of 1.7 ± 0.1 mm/year (1σ) from 5000 years BP to present. We compare the RSL changes with an ensemble of 1D (laterally homogenous) and site-specific 3D (laterally heterogeneous) GIA models, which tend to overestimate the magnitude of RSL rise over the last 5000 years. The continued discrepancy between RSL data and GIA models highlights the importance of using a wide array of ice model and viscosity model parameters to more precisely fit site-specific RSL data along the U.S. mid-Atlantic coast. Ministry of Education (MOE) National Research Foundation (NRF) Published version The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: JSW was funded by the David and Arleen McGlade Foundation and a Cushman Foundation for Foraminiferal Research Student Research Award. JSW and REK were also supported by US National Science Foundation awards OCE-1804999 and OCE-2002437. BPH, TL, and TS are supported by the Singapore Ministry of Education Academic Research Fund MOE2019-T3-1-004 and MOE-T2EP50120-0007, the National Research Foundation Singapore, and the Singapore Ministry of Education, under the Research Centres of Excellence initiative. NC is supported by the A4 project. A4 (Grant-Aid Agreement no. PBA/CC/18/01) is carried out with the support of the Marine Institute under the Marine Research Programme funded by the Irish Government. DCB receives support from the H.F. Alderfer Fund for Environmental Studies at Bryn Mawr College.

The southeastern China coast is a region of special interest in the study of past and present relative sea-level change, given its distal location from giant ice sheets (far-field regions). During the past decades, a large number of biological, geological, and archaeological sea-level indicators have been retrieved from the Fujian coastal region which allows for recalibration and recalculation of sea-level index points (SLIPs). This study constructs a database of Holocene relative sea-level (RSL) observations for the Fujian coast, southeastern China. The database contains 59 quality-controlled SLIPs which show that RSL for the Fujian coast did not exceed present (0 m) during the Holocene, except potentially during 7.5–5.5 cal. kyr BP and 1.8–0.7 cal. kyr BP. Rates of RSL change were highest during the early Holocene and have decreased over time, due to the diminishing response of the Earth's mantle to glacial isostatic adjustment (GIA) and reduction of meltwater input. A series of sea-level oscillations were recorded in our SLIPs-based reconstructions which might correspond to global climate warming or cooling events. We assessed the spatial variability of RSL histories and compared these with the ICE-6G_C and ANU-ICE GIA model predictions. Substantial misfits between GIA predictions and regional RSL reconstructions were recognized: (1) the deceleration of the early-Holocene sea-level rise ended about one millennia earlier in the ICE-6G_C model than in the SLIPs-based reconstructions; (2) GIA model predictions show a mid-Holocene sea-level highstand of 1–3 m which is absent from our SLIPs-based reconstructions; and (3) all GIA model predicted a gradual RSL fall to 0 m since the middle Holocene, while our reconstruction displays significant RSL oscillations. It is presently unknown whether these misfits are caused by uncertainties in regional tectonic movement estimation or parameters used in the GIA models. Future applications of spatiotemporal statistical techniques are required to better quantify the gradient of the isostatic contribution and to provide improved context for the assessment of the ongoing acceleration of sea-level rise. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version This work was financially supported by the National Natural Science Foundation of China (Grant No. 42076207 to Fengling Yu); the Funda- mental Research Funds for the Central Universities of Xiamen University (Grant No. 20720190096 to Fengling Yu); the China Postdoctoral Sci- ence Foundation (Grant No. 2021M691862 to Nannan Li); the Singapore Ministry of Education Academic Research Fund MOE2019-T3-1-004 and MOE-T2EP50120-0007, the National Research Foundation Singapore, and the Singapore Ministry of Education, under the Research Centers of Excellence initiative (to Tanghua Li).

We present an attempt to estimate the long-term changes in Relative Sea Level (RSL), in addition to the different factors contributing to such trends on a local and regional scale, using a statistical linear model. The time series analysis corresponded to 17 tide-gauges, grouped in three different areas: the northern and western Atlantic coasts of the Iberian Peninsula, the Canary Islands, and the southern and eastern coasts of the Iberian Peninsula and Balearic Islands. The analysis was performed for two periods: 1948–2019, using tide-gauge data; and 1993–2019, using both tide-gauge and altimetry data for comparison. The trends for the period 1948–2019 ranged between 1.09 ± 0.14 (Canary Islands) and 2.05 ± 0.21 mm/yr for the northern and western Atlantic Iberian Peninsula. Altimetry data during the period 1993–2019 yielded quite homogeneous results for all the locations and regions, ranging between 2.7 ± 0.4 and 3.0 ± 0.3 mm/yr. In contrast, the results obtained from tide-gauge data for this recent period showed a large dispersion, very likely due to local effects, or perhaps even to levelling or instrumental errors. Nevertheless, when the results were averaged for each area, the observed trends were comparable to the altimetry results, with values of 2.3 ± 0.8, 2.7 ± 0.5, and 2.8 ± 0.8 mm/yr for the three regions of study. A stepwise forward linear regression was used to relate the observed RSL variability to the atmospheric forcing and the thermosteric and halosteric components of the sea level. Surprisingly, the thermosteric and halosteric contributions were not significantly correlated to the observed RSL in many cases; consequently, the steric, the total addition of mass, the mass of salt, and the freshwater contributions to the observed sea level trends could not be reliably estimated. This result seems to have been the consequence of the scarcity of temperature and salinity data; this hypothesis was confirmed, with the exception of the tide-gauge data for L’Estartit. This location is close to a well sampled region. In this case, the atmospheric variables and the thermosteric and halosteric terms accounted for 80% of the observed RSL variance, and the contributions of these terms could be estimated. The freshwater contribution for this location was between 1.3 and 1.4 mm/yr, consistent with recent estimations of the contributions of glaciers and Greenland and Antarctica Ice Sheets. These results highlight the importance of monitoring programs and routine sampling for the determination of the different factors contributing to the sea level variability.

На юго-восточном побережье Унской губы, в районе д. Уны (Летний берег Белого моря) выполнены геоморфологические, георадиолокационные, палеолимнологические и геоархеологические исследования, а также дешифрирование детальных космических снимков. Восстановлены условия развития юго-восточных берегов Унской губы и их заселение представителями Беломорской культуры в голоцене. Задокументированы прерывистые фрагменты древних береговых линий на высотах, не превышающих 6-7 метров, фиксирующие верхний предел уровня моря в позднем голоцене., We present new data that were generated by intensive field surveys and comprehensive geological-geomorphological, geophysical and archaeological studies within the southeastern coast of the Unskaya Bay of the White Sea (Una village area; Arhangelsk region). The study is based on the results of geomorphological and ground-penetrating radar (GPR) profiling, interpretation of detailed space images and archaeological survey of the territory. As a result, we reconstructed relative sea level (RSL) changes within the southeastern coast of the Unskaya Bay and its initial settlement by pre-historic humans in the Holocene. We have documented discontinuous fragments of ancient coastlines at heights not exceeding 6-7 meters, which fix the position of the Late Holocene Sea.

In spite of the recent advances and the current perspectives of satellite radar altimetry to reach the coastline and monitor coastal sea level changes, this space-borne technology remains geocentric by essence. In contrast, the quantity that matters for coastal management and society is relative sea level. That is, the sea level relative to the land, as measured by conventional tide gauges. However, two important issues are associated with the use of tide gauges. First, supplemental information is required to separate vertical land motion from ocean climate signals in tide gauge records, and hence to understand the causes of future coastal sea level changes and their relative importance. This can be provided by space-borne geodetic techniques, for instance installing a permanent Global Positioning System (GPS) antenna at the tide gauge. Second, vertical land motion can show local spatial patterns, which limits the spatial validity of the point-wise information at the GPS station. Using Interferometry Synthetic Aperture Radar (InSAR) and high-precision GPS data, the above-mentioned limitations were addressed in the case study of Brest (France). Our findings show that, over the past decades, Brest and its surroundings are overall stable, in agreement with the geological setting, except for the embankment areas of the commercial and military harbours. The GPS-calibrated InSAR results were then further combined with geocentric satellite radar altimetry data to obtain relative sea level trends along the Brest coastline with an unprecedented high-spatial resolution of 200 m. Our approach is applicable beyond the case study of Brest, especially in coastal areas where tide gauge data are not available, provided satellite data are., Cyril Poitevin acknowledges a Ph.-D. grant from the French Research Ministry. This work benefited from the financial support of CNES (French space agency) through a TOSCA funding. Universitat de les Illes Balears provided a visiting professor grant for G. Wöppelmann. M. Marcos acknowledges support from the European INSeaPTION project (ERA4CS). G. Le Cozannet and D. Raucoules were supported by an internal BRGM grant. The SAR images from ERS-1/2 and Envisat satellite missions were downloaded freely with the support of ESA (European Space Agency) through the project Cat-1/19372. The Brest tide gauge and GPS data were obtained from SONEL (www.sonel.org).

This article reports on the dataset gathered following the census of 83 present-day Infralittoral Prograding Wedges (IPWs), surveyed on the inner continental shelf of the Central-Eastern Tyrrhenian Sea. The purpose of the census was to explore their bathymetric range and assess the observational laws governing this variability. The ensued dataset (Campania Region IPW Dataset, CRID) includes geographic, topographic and morpho-bathymetric indices, descriptive of each IPW and more, the exposure of each IPW to wave forcing (Geographical fetch, Effective fetch and extreme significant wave height, HS). In this work, histograms contribute to describe all the variables and highlight the dominant features of each IPW. Location maps univocally links the geographic position of each IPW to the appropriate attribute record in the dataset. Further, thematic maps illustrate eight wave fields obtained by offshore-to-nearshore transformation by as many sea states scenarios with 200-year return period. Such wave fields are used as sources for significant wave height representing wave conditions over each IPW. This dataset could be implemented with new measures at a broader scale, by following analogue procedures for measurements, to enlarge the observational scale on IPWs and improve the numerical models which might eventually derive by the analysis of this dataset.

A paucity of detailed relative sea-level (RSL) reconstructions from low latitudes hinders efforts to understand the global, regional, and local processes that cause RSL change. We reconstruct RSL change during the past ~5 ka using cores of mangrove peat at two sites (Snipe Key and Swan Key) in the Florida Keys. Remote sensing and field surveys established the relationship between peat-forming mangroves and tidal elevation in South Florida. Core chronologies are developed from age-depth models applied to 72 radiocarbon dates (39 mangrove wood macrofossils and 33 fine-fraction bulk peat). RSL rose 3.7 m at Snipe Key and 5.0 m at Swan Key in the past 5 ka, with both sites recording the fastest century-scale rate of RSL rise since ~1900 CE (~2.1 mm/a). We demonstrate that it is feasible to produce near-continuous reconstructions of RSL from mangrove peat in regions with a microtidal regime and accommodation space created by millennial-scale RSL rise. Decomposition of RSL trends from a network of reconstructions across South Florida using a spatio-temporal model suggests that Snipe Key was representative of regional RSL trends, but Swan Key was influenced by an additional local-scale process acting over at least the past five millennia. Geotechnical analysis of modern and buried mangrove peat indicates that sediment compaction is not the local-scale process responsible for the exaggerated RSL rise at Swan Key. The substantial difference in RSL between two nearby sites highlights the critical need for within-region replication of RSL reconstructions to avoid misattribution of sea-level trends, which could also have implications for geophysical modeling studies using RSL data for model tuning and validation. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version Authors were supported by National Science Foundation Awards (OCE-1702587, OCE-1831450, and OCE-2002437 to Kopp and Ashe; OCE-2002431, OCE-1458921, OCE-1831382, and OCE-1942563 to Kemp; OCE-1458903 to Engelhart). RPM is supported by the US Fish and Wildlife Service’s State Wildlife Grants Program (#F13AF00982). BPH is supported by the Singapore Ministry of Education Academic Research Fund MOE2019-T3-1-004 and MOE-T2EP50120-0007, the National Research Foundation Singapore, the Singapore Ministry of Education under the Research Centers of Excellence Initiative.

Fil: Beresford-Jones, David G. University of Cambridge; Reino Unido. Fil: Beresford-Jones, David G. University of Bonn; Alemania Fil: Friesem, David E. University of Haifa; Israel Fil: Fraser, Sturt. University of Southampton; Reino Unido Fil: Pullen, Alexander. Pre-construct Archaeology; Reino Unido Fil: Chauca, George. Universidad Nacional Mayor de San Marcos; Perú Fil: Moat, Justin. Royal Botanic Gardens; Reino Unido Fil: Gorriti, Manuel. Proyecto Especial Arqueológico Caral-Supe; Perú Fil: Maita, Patricia K. Museo Nacional de Arqueología, Antropología e Historia del Perú; Perú Fil: Joly, Delphine. University of York; Reino Unido Fil: Huaman Oros, Oliver. Universidad Nacional Mayor de San Marcos; Perú Fil: Lane, Kevin John. Consejo Nacional de Investigaciones Científicas y Técnicas. Universidad de Buenos Aires. Instituto de las Culturas; Argentina Fil: French, Charles. University of Cambridge; Reino Unido Shell middens are conspicuous manifestations of the exploitation of rich, sustainable, easily seen and harvested marine resources that, worldwide, enabled hunter-gatherers to reduce mobility and increase population and social complexity. Globally, known sites tend to cluster chronologically around 6 k BP, after slowing eustatic sea-level rise, although the Pacific coast of South America offers some rare earlier exceptions. We report investigations of La Yerba II, a Middle Preceramic shell matrix site on the Río Ica estuary, south coast Peru. These show how, beginning around 7000 Cal BP, over 4.5 m of stratigraphy accumulated in less than 500 years. Consisting of prepared surfaces, indurated floors and the ashy interiors of wind shelters and their associated midden deposits, alternating with phases of abandonment, this was the outcome of an intense rhythm of repeated occupations by logistically mobile marine hunter-gatherers. Final phases, dominated by Mesodesma surf clams, mark change towards more task-specific activities. La Yerba II's topographic position and well-preserved cultural and environmental markers provide insight into the local history of relative sea level change and changing marine hunter-gatherer lifestyles during a period critical to the transition to sedentism and the formation of new estuarine and beach habitats following the stabilisation of eustatic sea-levels. Beresford-Jones, D. G, Friesem, D. E., Fraser, S., Pullen, A., Chauca, G., Moat, J., Gorriti, M., Maita, P, K., Joly, D., Oliver, H., Lane, K. J. y French, C. (2022). Insights into changing coastlines, environments and marine hunter-gatherer lifestyles on the Pacific coast of South America from the La Yerba II shell midden, Río Ica estuary, Peru. Quaternary Science Reviews, 285, 107509.

The Sibari Plain (northeastern Calabria) shows a well-developed stair of late Quaternary marine/coastal terraces resulting from the interaction between sea level fluctuations and tectonic uplift. This paper (i) provides a stratigraphic description of terraced deposits between the Raganello and Coscile rivers, (ii) assesses the relative controls of eustacy and uplift on the staircase formation, and (iii) unravels the Quaternary morphosedimentary evolution of the study area. A geomorphological approach was coupled with stratigraphic field surveys. Photo interpretation, topographic map analyses, and field surveys allowed us to map ten orders of terraces forming telescopically incised valley-fills. Based on the uppermost position of foreshore deposits on inner margins and an average uplift rate of ~1 mm/y, inferred from the Marine Isotope Stage (MIS) 5.5, terraces were correlated with highstands. Sedimentological and stratigraphic analyses allowed us to recognize four assemblages of genetically associated sedimentary facies related to superimposed and juxtaposed coastal and alluvial systems, showing a seaward-stepping architecture. Based on stratal geometry and facies association, we argue that alluvial/fluvial sediments and coastal depositional systems formed contemporaneously along the same terrace. Terrace arrangement resulted from repeated cycles of valley incision (sea level fall) and aggradational to progradational stacking pattern (sea level rise and highstands) in a framework of sustained uplift.

Beachrocks are well known as significant proxies for paleoenvironmental analysis as they indicate the coastal evolution. The combination of geomorphological and archaeological sea level indicators has a significant contribution to the coastal paleogeographic reconstruction. In this study, we studied a beachrock from the Diolkos area (West Corinth canal, Greece) and remnants of Diolkos slipway to reconstruct the coastal evolution before Diolkos construction until today. We conducted detailed mapping of Diolkos beachrock using DGPS-GNSS, as well as mineralogical analysis and OSL dating of beachrock samples. The results showed that a beachrock slab was preserved before the construction of Diolkos below it, followed by its submergence by a co-seismic event after Diolkos abandonment during 146 B.C. Consequently, a new beachrock was developed on top of the submerged Diolkos around 120 ± 14 A.D. The RSL was stable until 1596 ± 57 A.D. when the beachrock developed even closer to the present-day coastline. After 1596 A.D., it was uplifted by 12 cm until it reached today’s condition.

The growth and decay of ocean-island volcanoes are intrinsically linked to vertical movements. While the causes for subsidence are better understood, uplift mechanisms remain enigmatic. Santa Maria Island in the Azores Archipelago is an ocean-island volcano resting on top of young lithosphere, barely 480 km away from the Mid-Atlantic Ridge. Like most other Azorean islands, Santa Maria should be experiencing subsidence. Yet, several features indicate an uplift trend instead. In this paper, we reconstruct the evolutionary history of Santa Maria with respect to the timing and magnitude of its vertical movements, using detailed field work and 40Ar/39Ar geochronology. Our investigations revealed a complex evolutionary history spanning ∼6 m.y., with subsidence up to ca. 3.5 Ma followed by uplift extending to the present day. The fact that an island located in young lithosphere experienced a pronounced uplift trend is remarkable and raises important questions concerning possible uplift mechanisms. Localized uplift in response to the tectonic regime affecting the southeastern tip of the Azores Plateau is unlikely, since the area is under transtension. Our analysis shows that the only viable mechanism able to explain the uplift is crustal thickening by basal intrusions, suggesting that intrusive processes play a significant role even on islands standing on young lithosphere, such as in the Azores.

Sea level changes can be driven by either variations in the masses or volume of the oceans, or by changes of the land with respect to the sea surface. In the first case, a sea level change is defined ‘eustatic’; otherwise, it is defined ‘relative’. Several techniques can be used to observe changes in sea level, from satellite data to tide gauges to geological or archeological proxies. Regardless of the technique used, ‘eustasy’ cannot be measured directly, but only calculated after perturbing factors of different origins are taken into account. In this paper, we review the meaning and main processes that contribute to eustatic and relative sea level changes, and we give an overview of the different techniques used to observe them.

The sea and land change elevation spatially and temporally from a multitude of processes, so it is necessary to constrain the movement of both to evaluate how coastlines will evolve and how those evolving coastlines will impact the natural and built environment over time. We combine land movement observations from global navigation satellite systems (GNSSs), leveling of geodetic monuments, and tide gauge records with a tectonic model of the Cascadia subduction zone to constrain absolute rates of vertical land movement in coastal Washington. We infer rates of vertical land movement in areas lacking direct observations by interpolating high-quality land movement observations and a discretely sampled interseismic locking model. Here we present a model of absolute vertical land movement that is combined with sea level rise estimates to inform local relative sea level projections on a community-scale. The most rapid vertical uplift (~3.5 mm/year) of the land is found across the northwest Olympic Peninsula, which currently outpaces sea level rise. Conversely, some areas, including a stretch of the northern Pacific Ocean coast from La Push to Kalaloch and the southern Puget Sound, are found to be subsiding at 0.5&ndash, 1.0 mm/year, exacerbating the rate of relative sea level rise and thereby increasing the vulnerability of coastal communities.

Land subsidence has played and is still playing a significant role in coastal wetlands worldwide and in palaeogeographical reconstructions of such wetlands. The varying thickness of compaction-prone sediments over a stable subsurface is a key factor in determining its magnitude and in locating the most affected areas. In the coastal low-lying Agro Pontino (Lazio, Italy), subsidence of the past 90 years has been mapped using historical elevation data. Due to the fortunate preservation of distal Avellino tephra (AV-tephra, ca. 1900 cal. BCE) within its marshy strata, discovered a decade ago, detailed palaeogeographical reconstruction of the landscape in preparation for an assessment of its land use suitability in the Early Bronze Age (EBA) was possible. Current altitude variations of water-lain tephra in lake areas assumed to be connected necessitated a closer look at its original deposition altitude and the role of post-depositional subsidence. Recent subsidence patterns proved very useful for distinguishing stable from subsidence-prone areas. Two different EBA palaeo lake environments are distinguished: an inland and a near-coastal lake. The AV-tephra altitude variation within these lakes partly marks differential post-depositional subsidence within these lakes. Calculation of initial ripening of tephra-bearing lake deposits on top of shallowly buried Pleistocene ridges allowed for an estimation of original tephra deposition altitudes and associated lake levels. For the inland lake, a wide lake edge zone between 0.5 and 2 m above current sea level (m asl) was reconstructed, where EBA habitation or land use was possible. At the near-coastal lake, a water level of −1.5 to −1.3 m asl at the time of AV-tephra deposition was constrained. Because tephra deposition occurred here just after marine influence ceased, this altitude range is proposed to be a Relative Sea Level (RSL) index point at the time of AV-tephra deposition. The altitude range is in agreement with RSL models for tectonically stable areas in this region. The importance of subsidence in palaeogeographical, water level and RSL reconstructions in the region is stressed.

Relative sea-level (RSL) reconstructions are essential to answer a variety of scientific questions, ranging from the investigation of crustal movements to the calibration of earth rheology models and ice sheet reconstructions. It is generally assumed that most Cycladic islands (Aegean Sea, Greece) are affected by a gradual subsidence, attributed to the crustal thinning and to hydro-isostatic processes that accompanied the post-glacial rise in sea level. In this paper, we produce new RSL data from sedimentary records on Paros Island. We compare and contrast these RSL data with published data from the nearby island of Naxos. Our results are further compared with sea-level predictions from two different GIA models in an attempt to better quantify the tectonic regime of the wider study area. Our results suggest average tectonic subsidence rates close to 1.0 ± 0.4 mm/yr since 5500 cal BP. These rates are not linear in time and have increased since 2500 cal BP.

Rising global sea level caused by melting ice sheets poses a major challenge ina persistently warming climate. The Greenland Ice Sheet (GrIS) is among the maincontributors, and in order to make accurate predictions of future ice retreat and sealevel rise, it is imperative to understand how the ice sheet responded to global warming in the past. Reconstructions of relative sea level (RSL) are a key constraint in models of past ice sheet fluctuations, however, high-precision data has until now been sparse in North Greenland. In this study, we present a RSL reconstruction for Finderup Land, North Greenland based on five isolation lakes located between 19.6 and 81.2 m a.s.l. The transition between marine and lacustrine sediments has been identified using XRF, lithological interpretation, and foraminiferal analysis. Age constraints are based on 14C dating of foraminifera and paleomagnetic age correlation. Our results show that Finderup Land was ice free by 10.8 0.2 cal ka BP with a subsequent rapid RSL fall occurring from 9.5 0.2 to 8.0 cal ka BP, at which point the RSL started to approach present level. Furthermore, we establish the marine limit to be minimum at 81.2 m a.s.l. We compare our data to modeled RSL predictions for the area and our results indicate a faster RSL fall, which in turn reflects that the ice retreat was more rapid than estimated and possibly, that the ice sheet in North and Northeast Greenland was larger than previous estimates suggest.

A contribution to the PAGES' PALSEA2 Working Group. ABSTRACT: This paper presents new Holocene relative sea level (RSL) data collected from isolation basins close to the town of Paamiut in south west Greenland. The data shows a rapid fall from a marine limit of c. 52masl at c. 10.9cal.ka BP to close to present by c. 9.5cal.ka BP at rates of up to c. 32mm/yr falling below present for the majority of the Holocene before rising to present in the last 2000 years. The elevation of the RSL lowstand is not well constrained but was at least below 3m. This pattern of rapid RSL fall during the early Holocene matches the pattern seen at other southern Greenland locations suggesting rapid largely simultaneous ice retreat from the area surrounding the Qassimiut Lobe at the start of the Holocene occurring c. 2000 years after the initial deglaciation of the extreme southern tip of Greenland. The RSL histories from this and other southern Greenland locations are distinct to those recorded further north along the west coast and are in broad agreement with a pattern of vertical land motion and RSL predicted by the Huy2 model (Simpson etal. 2009) which predicts an 80m drop in the contribution of vertical land motion to RSL at 10cal.ka BP between Sisimiut and Paamiut on the west coast. Despite this broad scale spatial agreement between the RSL data and the Huy2 model it fails to satisfactorily predict the Holocene RSL histories at Paamiut and other southern Greenland locations. Sensitivity tests indicate that the data model misfits are most likely due to an over estimate of the forcing during the Holocene Thermal Maximum (or the response to this forcing) in southern Greenland and error in the North American ice sheets component of the background deglaciation model. Our new data suggests that much of the southern part of the ice sheet acted differently to the area further north. However RSL changes at Paamiut are also largely impacted by regional and larger scale processes including a bulls eye of uplift centred on the west the impact of the Holocene Thermal Maximum and the influence of the collapse of the North American ice sheets. © 2013 Elsevier Ltd.

We present relative sea level (RSL) curves in Antarctica derived from glacial isostatic adjustment (GIA) predictions based on the melting scenarios of the Antarctic ice sheet since the Last Glacial Maximum (LGM) given in previous works. Simultaneously, Holocene-age RSL observations obtained at the raised beaches along the coast of Antarctica are shown to be in agreement with the GIA predictions. The differences from previously published ice-loading models regarding the spatial distribution and total mass change of the melted ice are significant. These models were also derived from GIA modelling; the variations can be attributed to the lack of geological and geographical evidence regarding the history of crustal movement due to ice sheet evolution. Next, we summarise the previously published ice load models and demonstrate the RSL curves based on combinations of different ice and earth models. The RSL curves calculated by GIA models indicate that the model dependence of both the ice and earth models is significantly large at several sites where RSL observations were obtained. In particular, GIA predictions based on the thin lithospheric thickness show the spatial distributions that are dependent on the melted ice thickness at each sites. These characteristics result from the short-wavelength deformation of the Earth. However, our predictions strongly suggest that it is possible to find the average ice model despite the use of the different models of lithospheric thickness. By sea level and crustal movement observations, we can deduce the geometry of the post-LGM ice sheets in detail and remove the GIA contribution from the crustal deformation and gravity change observed by space geodetic techniques, such as GPS and GRACE, for the estimation of the Antarctic ice mass change associated with recent global warming.

New data on the ancient landscape of Naples (southern Italy) during the middle and late Holocene from geo-archaeological excavations associated with public transport works were used to reconstruct the hill and coastal environment to the west of the ancient Graeco-Roman polis, where remains of human settlements date to the late Neolithic. The rich stratigraphic and archaeological records that emerged from the digs and from previous boreholes were measured and analysed by combining sedimentary facies analysis, tephrostratigraphy and archaeological data. Between the 5th and 4th millennia BP, a rocky profile with a wave-cut platform cutting across pyroclastites emplaced from the surrounding volcanoes was predominant in the coastal landscape. During the 3rd millennium BP, this rocky coast was progressively replaced by a sandy littoral environment primarily due to marine deposition, with a coastline located some hundred meters inland with respect to the modern one. The sedimentary record of the Greek and Roman periods indicates short-term fluctuations of the coastline, leading to the establishment of a backshore environment towards the end of the 6th century AD, when prograding river mouths and lobes of debris flows contributed to the advancing trend of the shoreline. The frequent archaeological remains from these periods indicate a stable settled area since Roman times. The shoreline was still subject to short-lived fluctuations between the 12th and 16th centuries, and attained its present position during the modern era with man-made reshaping of its profile. The construction of Relative Sea Level curves for two coastal sites reveals that the persistence of the foreshore environment in the Naples coastal strip during the 5th and 4th millennia BP was controlled by the counterbalancing effect of either the concurrent eustatic sea level rise or subsidence. On the other hand, the morpho-stratigraphic record for the last two millennia shows a significant correlation between sedimentation rate and settlement history, accounting for the dominant role of the anthropogenic forcing-factor in late Holocene landscape history. In particular, land mismanagement during Late Antiquity seems to have triggered a slope disequilibrium phase, exacerbating soil erosion and increasing the sediment accumulation rate in both foothill and coastal areas. Nonetheless, the environmental changes of the Chiaia coast during the last 2000 years clearly show volcanic–tectonic perturbations influencing coastline development up to the modern era.

This paper presents new evidence regarding relative sea-level (RSL) changes and vertical land motions at three sites in Greenland since 1300 A.D., a time interval that spans the later part of the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA). We observe RSL rise at two sites in central west Greenland from c. − 0.80 ± 0.20 m at c. 1300 A.D. to c. − 0.20 m ± 0.25 m at c. 1600 A.D., after which RSL slowed and then stabilised. At a third site in south Greenland, we observe RSL rise from c. − 1.40 ± 0.20 m at c. 1400 A.D. until c. 1750 A.D., after which RSL slowed and was stable during at least the latter part of the 20th century. The c. 1600 A.D. RSL slow-down seen at the two former sites is surprising because it occurs during the LIA when one might expect the ice sheet to be gaining mass and causing RSL to rise. We interpret this RSL slowdown to indicate a period of enhanced regional mass loss from central west Greenland since c. 1600 A.D. and propose two hypotheses for this loss: first, a reduction in precipitation during cold and dry conditions and second, higher air temperatures and increased peripheral surface melt of the ice sheet from this date onwards. The latter hypothesis is compatible with a well-established temperature seesaw between western Greenland and northern Europe and, potentially, a previously identified shift from a positive to generally more negative NAO conditions around 1400 to 1600 A.D. Our study shows how RSL data from Greenland can provide constraints on the timing of ice sheet fluctuations in the last millennium and challenges the notion that during cold periods in northern Europe the ice sheet in west Greenland gained mass.

A 2.73 m long sediment sequence from Loon Lake, located at 18m a.s.l. on outer Geographical Society Ø, East Greenland, was investigated for its chronology and changes in physical and biogeochemical properties, macrofossils, and grain-size distribution. The predominance of marine fossils throughout the sequence, dated by 14C AMS to between 8630 and 7535 cal. yr BP, shows that the Loon Lake at that time was a marine basin, which according to existing sea-level curves was about 15-35 m deep. The sequence mainly consists of fine grained homogeneous sediments, which are interrupted by a 0.72 m thick sandy horizon with erosive basis and distinct fluctuations in the grain-size distribution and in the physical and biogeochemical properties. According to the radiocarbon dates, this sandy horizon was deposited after 8500-8300 cal. yr BP and is interpreted as originating from the Storegga tsunami. The record from Loon Lake provides the first indication of Storegga tsunami deposits from East Greenland. Copyright © 2006 John Wiley & Sons, Ltd.

Holocene sea-level reconstructions exist from many locations in the Indo-Pacific region. Despite being a large geographical region, the nature of Holocene sea-level change is broadly similar in all locations. Differences do exist, however, in the timing and magnitude of the Mid-Holocene High Stand (MHHS) and the nature of late Holocene sea level fall across the region. When the Indo-Pacific is subdivided into smaller regions, these discrepancies do not disappear, and in some cases the discrepancies are large within a single coastline. It is clear from this analysis that the fundamental criteria to produce accurate local relative sea-level curves are hardly ever met. There are serious problems associated with the correct interpretation of sea-level indicators and their relationship to mean sea level, and with the quality of age determinations. A consistent methodology throughout the Indo-Pacific for the analysis of sea level data is lacking. Future sea-level analysis from far field locations must involve the application of a consistent methodology in order to allow meaningful comparison between studies. This should help to resolve the ongoing debate about the magnitude and timing of the Mid-Holocene High Stand, and the nature of late Holocene sea-level fall across the region.

Έπειτα από την ανακάλυψη ενός πλατύ λιθόστρωτου δρόμου, του οποίου η διεύθυνση είναι από νοτιοδυτικά προς βορειοανατολικά και διακόπτεται απότομα από τη σημερινή ακτογραμμή, Ελληνιστικής περιόδου γεννήθηκε η υποψία από τους υπεύθυνους αρχαιολόγους της ανασκαφής ότι στην ευρύτερη περιοχή θα μπορούσε να υπήρχε κάποιο αρχαίο λιμάνι. Για τον έλεγχο της υπόθεσης αυτής έγινε μια συντονισμένη γεωμορφολογική έρευνα στο ρηχό θαλάσσιο και στο παράκτιο τμήμα του Όρμου Μεγάλου Καβουρίου. Ο θαλάσσιος πυθμέναςερευνήθηκε με μονοδεσμικό βυθόμετρο, ηχοβολιστή πλευρικής σάρωσης και ελεύθερες καταδύσεις. Από τα συλλεχθέντα στοιχεία προέκυψαν ένας βαθυμετρικός χάρτης, ένας χάρτης με τους τύπους υποθαλάσσιου αναγλύφου, πλήθος γεωαναφερμένων επίγειων και υποβρύχιων φωτογραφιών, και ένας γεωμορφολογικός χάρτης της παράκτιας περιοχής. Από αξιολόγηση των αποτελεσμάτων εντοπίστηκε ένας υποθαλάσσιος χώρος, στα νοτιοδυτικά της περιοχής μελέτης, ο οποίος συγκεντρώνει τις κατάλληλες προϋποθέσειςγια να χαρακτηριστεί ως πιθανή θέση ασφαλούς αγκυροβολίου ή λιμενισμού σκαφών στο παρελθόν., The discovery of a paved Hellenistic road, which was ended at the shoreline of the Megalo Kavouri bay in Attica, Greece, led the archaeologists to hypothesize that an ancient harbour would be located somewhere at the adjacent submarine area. For the identification of the position of this harbour, a joint submarine and littoral geomorphological survey was carried out. The oceanographic mission was conducted in order to map the underwater landforms. A variety of geomorphological characteristics, types of substrate and habitats (i.e., rocky outcrops, boulder or gravel accumulations etc.) and anthropogenic objects (i.e., debris of recent construction material) were identified in the shallow water seabed of the Kavouri Bay. The littoral geomorphological survey was carried out to determine the natural processes affecting the continental part of the area and map the coastal landscape features. Data derived by both submarine and littoral geomorphological investigations indicate that the most probable location of the harbour could be situated in the southern part of the study area.

The study area corresponds to the coastal plain neighboring the Ribeira de Iguape river mouth in the Sao Paulo State littoral, where the Iguape, Cananeia and Ilha Comprida municipalities are situated. This coastal plain exhibits an area of more than 1,500 km². It has been interpreted as a consequence of shallow marine sedimentation of Pleistocene and Holocene, attributable to Cananeia and Santos transgressions, occurred during the last two interglacial stades named Sangamon and Holocene, intercalated by the last glacial stade named the Wisconsin according to the North-American nomenclature. However, without any scientific fully justifiable evidence, it has been hypothetically postulated that this coastal plain could represent an oceanic delta associated with the Ribeira de Iguape river mouth, which is the most important drainage along the Sao Paulo State coastline flowing to the Atlantic Ocean. This article has presented the data obtained by essentially sedimentological studies, based on grain size and heavy mineral analyses, which brought important subsidies for a negative response to the question: "is there a true delta at the Ribeira de Iguape river mouth (Sao Paulo State, Brazil)?".

cited By 8; International audience; By means of a stratified viscoelastic Earth model we study the effect of sinking slabs on the dynamic topography, the non-hydrostatic geoid and the long-term sea level variations. Sea level fluctuations due to subduction are found to be sensitive to the nature of the 670 km seismic discontinuity and to the rheological layering of the mantle. The response of our model to both a single subduction and a realistic distribution of slabs is studied by a numerical simulation based on a simplified approach. Consistent with previous results, we find that an upper bound to relative sea level time variations associated with the initiation of a new subduction in the upper mantle is ∼ 0.1 mm/yr. Relative sea level changes driven by the dynamic readjustment of internal mass heterogeneities may thus be comparable with those attributed to other changes in the tectonic regime on a large scale. This confirms the relevance of subduction as an important contributor to long-term sea level fluctuations. Copyright 1997 by the American Geophysical Union.