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Graphical abstract Highlights • Sediment grain sizes of a South China Sea core reveal paleoenvironment change from 36 kyr BP. • High sea levels promoted (impeded) the ∼0–2 μm (∼15–100 μm) component. • Low sea level and favorable topography close to estuary caused a layer of turbidite. • The ∼2–10 μm component records climate changes dominated by the East Asian monsoon. Abstract Sediment grain size is an important proxy to detect sedimentary process and record paleoenvironmental variations in continental slopes. Grain size measurements were performed for 298 samples of the 5.96-m-long core PC338 spanning the past 36 kyr recovered from the northern South China Sea (SCS). Results show that sea level and climatic influences on grain size distributions are crucial. A turbidite formed during the Last Glacial Maximum (LGM) is ascribed to the favorable topography close to the Red River estuary induced by the low sea level. Four end-member (EM) components for the normal sediment layers were unmixed using a lognormal parametric end member modeling (EMM). With the sea level decreasing, more EM4 (∼15–100 μm) and less EM1 (∼0–2 μm) supplied the SCS slope. Because EM2 (∼2–10 μm) consisted of fluvial suspension is dominated by the East Asian summer monsoon (EASM) precipitation, it has the potential to substitute for the EASM intensity. EM2 varied in-phase with many south China paleoclimate records and the 30°N July insolation over the past 36 kyr, and cooling climate events (including the LGM, Heinrich events H1 and H3, Younger Dryas, 8.2 ka and 10.3 ka) lowered the EM2 content. Our results further confirm the synchronous EASM evolution in the South China continent mainly forced by the Northern Hemisphere summer insolation. [ABSTRACT FROM AUTHOR]

Abstract A primary goal of geomorphology is to infer from topographic form the processes that drive landscape evolution. Often implicit is the assumption that orogen-scale (> 10 10 m2 planform area) transient landscape changes on Earth are driven by equally large-scale transient tectonics, climate, or sea level. Here we argue that meso-scale (105–1010 m2) uplift perturbations may affect landscapes on scales that far exceed their size and duration. We study the consequences of transient variations in uniform surface uplift that are localized in space, such as may occur in volcanic landscapes or during landslide emplacement. These localized uplift perturbations define a class of landforms that are larger than typical hillslope lengths but smaller than orogens, and grow at rates that are rapid compared to fluvial bedrock erosion. We use 1D and 2D landscape evolution models to show that uplift perturbations drive transient lateral migration and vertical amplification of nearby ridges, sometimes generating a spatially distributed imbalance between uplift and erosion that causes plateau-like topography. Relaxation to steady-state conditions, in which erosion balances uplift everywhere, depends on the degree to which wave-like adjustment within channels or of ridges dominates subsequent landscape erosion. We find that the spatial structure and timescales of landscape response are predictable given uplift perturbation parameters. In 2D models, localized uplift generates a radial pattern of channel network and drainage divide reorganization that remains long after the perturbation is eroded. The spatial pattern of ridges and channels in a landscape thus may record both the scale and pace of perturbations to the uplift field. Highlights • Transient, localized uplift perturbations drive large-scale landscape response. • Nearby ridges are focused towards localized uplift and are transiently amplified. • Distributed erosion imbalances drive transient plateau formation and drainage capture. • Topographic steady state is easily and permanently disrupted by uplift perturbations. • Transient divide migration speed depends both on hillslope and fluvial processes. [ABSTRACT FROM AUTHOR]

Abstract Grain size, clay mineralogy, 87Sr/86Sr, εNd, and AMS14C analyses of deep-sea sediments cored in the central Bay of Bengal are used to reconstruct the evolution of provenances and climate control since the last glacial period. Clay minerals, 87Sr/86Sr ratios and εNd values indicate a mixture of sediment from the Himalaya source, Indian Peninsula and Indo-Burman Ranges/Irrawaddy River. These analyses show that the Himalaya Mountains and Indo-Burman Ranges/Irrawaddy River are the main suppliers before the Holocene period, while the inputs of erosion materials from the Indo-Gangetic floodplain and the Indian Peninsula increase during the Holocene period, accompanied by reduced inputs of the Indo-Burman Ranges and Irrawaddy sediments. The regional "source-sink" process is significantly controlled by the climate. Warm and wet climate conditions and enhanced Indian monsoon intensity during the Holocene period are responsible for the increase of sediment input from the Indo-Gangetic Plain and the Indian Peninsula by improving erosion in the source area, input from the floodplain to the river channel and the intensity of the southwest monsoon current. In contrast, due to the decrease of the northeast monsoon current during the Holocene period, sediment input from the Irrawaddy and Indo-Burman Ranges are constrained. Deposition center transition between the submarine fan and shelf during the last glacial period and the Holocene period occurs in response to the sea level change, which controls the sedimentary mode and thus significantly influences the transportation and deposition processes in the Bay of Bengal (BoB). [ABSTRACT FROM AUTHOR]

Inner shelf to shelf-margin delta and slope-fan deposits in the Cenozoic Pearl River Mouth Basin in the northern continental margin of the South China Sea comprise the most important petroleum reservoirs in the basin and their evolution reflects a changing interplay of tectonics, sea level change and sediment supply. Integrated analysis of 3D seismic, well logs and core data allows interpretation of depositional architecture and evolution of the delta systems as they responded to the major controls. Inner shelf-delta systems, sited on the landward reaches of the continental margin, are characterized by thickly stacked distributary channel, thin (20-40 m) but relatively coarse delta-front and thin, fine-grained, distal delta to prodelta deposits. In contrast, outer shelf to shelf-margin deltaic systems formed 200 m (merging outwards to 1000 m) high clinoforms with steep slopes imaged on 3D seismic profiles as S-shape or tangential progradational reflections. Slumps and debris flow as well as sandy turbidite slope-fan deposits are common on the slopes of the clinoforms. Basinward and landward, cross-shelf transits of the delta systems are evident, as they formed some 18–20 stacked, high-frequency transgressive-regressive deltaic cycles (0.8–3 Myr) and five megacycles (3 to 10 Myr). Development of the deltaic cycles is interpreted as the result of high-amplitude sea level falls and rises related to glacio-eustasy as well as to changing sediment supply. The large-scale transgressive-regressive evolution of the deltaic clastic wedge is likely to have been controlled mainly by long-term changes in tectonic subsidence rate and sediment supply. The shelf-edge deltaic regressions are likely to have developed during sea level fall, but also during periods of high sediment input enhanced by uplifted tectonic relief and catchment enlargement or at times by monsoonal intensification events. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO 2 ) is one of the main sources of global warming, rising sea levels, and frequent outbreaks of extreme weather. China is now one of the largest energy consumer and CO 2 emitters in the world. As one of China's economic centers, Shanghai city has a perfect industrial system with large industrial scale. The industrial sector is an energy– and emission–intensive industry, which contributes the significant part of CO 2 emissions in Shanghai city. Therefore, an in–depth investigation of the main driving forces of CO 2 emissions in the industrial sector is essential to reduce CO 2 emissions in the city. This study uses Vector Autoregressive model to analyze the main factors causing the increase in CO 2 emissions in the industrial sector. The results show that economic growth leads to an increase in CO 2 emissions in the short run, but is conducive to reducing CO 2 emissions in the long run, due to the differences in fixed–asset investment and export trade. Energy consumption structure leads to a growing CO 2 emissions in the short term, and is beneficial to mitigate CO 2 emissions in the long term, owing to the gradual optimization of energy consumption structure. However, urbanization helps to reduce CO 2 emissions in the short term, but leads to an increase in CO 2 emissions in the long term, because of urban real estate and infrastructure construction investments as well as vehicle use. Energy efficiency leads to an increase in CO 2 emissions both in the short and long run since the scale effect exceeds the technical effect. Industrial structure produces a positive effect in the short run, but the impact is gradually narrowing in the long run. [ABSTRACT FROM AUTHOR]

Simulated signals from Global Navigation Satellite Systems (GNSS), reflected off the sea surface and received aboard low Earth orbiting satellites, have been used to derive sea surface height (SSH) and assimilated into an ocean model in an Observing System Simulation Experiment (OSSE). The experimental approach is named GNSS Reflectometry (GNSS-R), which was proposed for the International Space Station (ISS). This scientific experiment was conducted in the frame of the ESA mission called “ G NSS R E flectometry, R adio O ccultation and S catterometry aboard the International Space Station” (GEROS-ISS). In this study, three sources of uncertainties of the planned GNSS-R altimeter are considered by the GNSS-R simulator: the troposphere, the ionosphere, and a noise term. An ensemble optimal interpolation (EnOI) data assimilation system is set up for an eddy-resolving HYbrid Coordinate Ocean Model (HYCOM) of the South China Sea (SCS), and two data assimilation runs are performed from the 18th June to the 31st July 2014 with and without GNSS-R. In the run assimilating GNSS-R, the measurements come in addition to traditional Sea Level Anomalies (SLA) from present-day altimeters. In spite of the lower precision of individual GNSS-R retrievals, the results obtained in July show an overall improvement of the Root Mean Squared Difference (RMSD) by 14%, compared to traditional altimeter data only. Considering the crossing of Typhoon Rammasun through the SCS, the GNSS-R data improve the realism of the three largest eddies. The temperature sections along the typhoon track show large differences in the upper 200 m depths in excess of 1 °C near the shelf break. Finally, diagnostics of Degree of Freedom for Signal (DFS) provide a quantitative Impact Factor (IF) of the GNSS-R altimetry data over the conventional altimeter data. On average in July, the IF is low (<5%), but for the period of the typhoon it reaches values over 20%. This indicates the complementary of the GNSS-R altimetry data to the present observing system, especially in filling the gaps of the traditional altimeters. [ABSTRACT FROM AUTHOR]

Unique location in the land-sea interface makes mangrove ecosystems most vulnerable to the impacts of predicted sea level rise due to increasing anthropogenic CO 2 emissions. Among others, carbon sink function of these tropical ecosystems that contribute to reduce rising atmospheric CO 2 and temperature, could potentially be affected most. Present study was undertaken to explore the extent of impact of the predicted sea level rise for the region on total organic carbon (TOC) pools of the mangrove ecosystems in Negombo estuary located on the west coast of Sri Lanka. Extents of the coastal inundations under minimum (0.09 m) and maximum (0.88 m) sea level rise scenarios of IPCC for 2100 and an intermediate level of 0.48 m were determined with GIS tools. Estimated total capacity of organic carbon retention by these mangrove areas was 499.45 Mg C ha − 1 of which 84% (418.98 Mg C ha − 1 ) sequestered in the mangrove soil and 16% (80.56 Mg C ha − 1 ) in the vegetation. Total extent of land area potentially affected by inundation under lowest sea level rise scenario was 218.9 ha, while it was 476.2 ha under intermediate rise and 696.0 ha with the predicted maximum sea level rise. Estimated rate of loss of carbon sink function due to inundation by the sea level rise of 0.09 m is 6.30 Mg C ha − 1 y − 1 while the intermediate sea level rise indicated a loss of 9.92 Mg C ha − 1 y − 1 and under maximum sea level rise scenario, this loss further increases up to 11.32 Mg C ha − 1 y − 1 . Adaptation of mangrove plants to withstand inundation and landward migration along with escalated photosynthetic rates, augmented by changing rainfall patterns and availability of nutrients may contribute to reduce the rate of loss of carbon sink function of these mangrove ecosystems. Predictions over change in carbon sequestration function of mangroves in Negombo estuary reveals that it is not only affected by oceanographic and hydrological alterations associated with sea level rise but also by anthropogenic processes, therefore the impacts are site specific in terms of distribution and magnitude. [ABSTRACT FROM AUTHOR]

Different multidisciplinary data concerning the paleodynamics of sea-level variations in the Caspian and Black seas are controversial in some aspects. There are at least three paradoxes that are discussed in the paper. The Paradox No. 1 relates to the Early and Late Khvalynian transgressions that occurred in the CS during the second part of MIS 3 (∼35–25 ka BP) and the Late Glacial epoch (∼17–12 ka BP), respectively. It is unclear what the main source or sources of water were that caused them. Paradox No. 2 emerges from the comparison of climate events and transgressive-regressive cycles in the Caspian Sea and the Black Sea. It implies that large sea-level anomalies occurred in accordance with global climate changes (because they are influenced by climate variations). However, other (not so long-lived) sea-level fluctuations are poorly correlated with climate events. The question is why climatically-induced sea-level changes did not follow climatic variations. Paradox No. 3 concerns the contradiction between the massive water discharge from the Black Sea into the Sea of Marmara via the Bosphorus Strait and the Black Sea level fluctuations in the Latest Pleistocene-Holocene that could not exist simultaneously. It is shown that Paradox No. 2 has been solved, at least on conceptual level. Solutions to Paradoxes No. 1 and No. 3 are still lacking: further geological and geochronological evidence as well as climate simulation are required. Formulation of solutions for these paradoxes should make a major contribution not only to the problems of the Caspian and Black seas’ paleogeography, but also provide help in explaining the reasons for inadequate simulation of regional climate changes. This is important in the context of the development of models for future climate prediction. [ABSTRACT FROM AUTHOR]

The analysis of seismic-acoustic profiles and drilling data from the Northern Caspian showed the climatic events are quite distinguishable in the Upper Pleistocene sedimentary sequence. The climatic events of the first half of Late Pleistocene (MIS 5) resulted in the onset of two warm-water transgressive basins – Late Khazarian and Hyrcanian ones. Though cooler than at the late Khazarian transgression, the climate during the Hyrcanian time was attributable to interglacial one. As the glacial stage MIS 4 approached its maximum under conditions of a dry and cold climate the Hyrcanian sea basin regressed. The Atelian regression of the Caspian Sea corresponded to MIS 4 stage and to the initial phases of the MIS 3 interstadial warming. The development of the global interstadial warming led to a considerable increase in the surface runoff from the catchment and resulted in the rising of the Atelian lake level and the onset of the first phase of the Khvalynian transgression. The sea level rising was interrupted at the time of maximum cooling and aridization at MIS 2 and resumed when the ice sheet was decaying. The conspicuous climatic events known as warm phases of Bølling and Allerød promoted the ice sheet melting along with thawing of permafrost, the latter having been widespread in the Volga drainage basin. All the above contributed to the Khvalynian transgression. The ‘chocolate’ clays were accumulated in the Volga estuary, as well as in depressions of the Pre-Khvalynian topography. Phases of a noticeable cooling known as the Oldest, Older and Younger Dryas marked by a decrease in the runoff volume from the Caspian drainage basin are correlated with regressive stages in the Khvalynian basin history. The Khvalynian came to its end at the time of the first sharp warming that resulted in the rise of the Caspian level and is generally taken as marking the Pleistocene/Holocene boundary. The Mangyshlakian regression is dated to the Holocene and was essentially a response of the Caspian Sea to the increase in the climate continentality during the Boreal period. [ABSTRACT FROM AUTHOR]

This study investigates how primary production responded to changes in nutrient availability, sea-level, and sea-ice coverage at the Umnak Plateau during Marine Isotope Stage (MIS) 5 and parts of MIS 4 and MIS 6. The Umnak Plateau during MIS 4 and MIS 6 had low primary production resulting from extensive sea-ice coverage that enhanced stratification and limited nutrient replenishment. This nutrient limitation was relieved during the deglaciation going into MIS 5 when previously exposed continental shelves were flooded and the eastern Aleutian Island passes were opened by an increase in sea-level, resulting in an increase in productivity. Opening and closing of the eastern Aleutian Island passes during the rest of MIS 5 reflected fluctuations in sea-level and likely affected nutrient sources and productivity at the Umnak Plateau. Nutrients during sea-level lowstands were likely sourced by the Aleutian North Slope Current, whereas most of the sea-level high stands throughout MIS 5 had nitrogen sourced by an increase in nitrogen fixation and the assimilation of remineralized nitrogen, which led to highly depleted nitrogen isotope values never before seen for the northern Pacific. Higher sea-level and productivity near the beginning of MIS 5 likely reflected MIS 5e; however, a discrepancy between two diatom productivity proxies suggests that changing environmental conditions stimulated a change in the dominant diatom species. This highlights the complexities associated with productivity in the Bering Sea and emphasizes the need to continue studying how productivity and ecosystems changed during previous warm periods. [ABSTRACT FROM AUTHOR]

The largest collection of tide gauge records assembled to date, called GESLA-2, has been used to provide reliable extreme sea level parameters at 655 locations around the world. This has enabled a rigorous assessment of the European Union-funded DINAS-COAST (D-C) data set of extreme sea level information for the global coastline that has been used in many published flood impact studies. We find the D-C extreme levels to be generally both too high, compared to those from GESLA-2, and too flat, when plotted as a function of return period. This leads to an over-estimation of the probability of extreme sea levels in the present day for most locations around the world, and also to an over-estimation of the probability of extreme sea levels in the future as sea level rises. A detailed impact study is conducted for the world's largest coastal cities following the approach of Hallegatte et al. (2013), resulting in similar conclusions for these particular locations. We suggest that most previous studies that have relied upon D-C information should be re-assessed in the light of these findings, using more recent modelling-based estimates of extreme sea level information. [ABSTRACT FROM AUTHOR]

This study found an unusually large variation in the coastal sea level difference (SLD) in the southwestern Japan Sea from July to October 2013. The time and horizontal scales were about 4 months and 1000 km along the coast, respectively. During the exceptionally hot summer of 2013, strong monsoon winds blew through the Tsushima Straits into the southwestern Japan Sea, because the North Pacific High was located farther west than average. The southwesterly winds averaged 7 m s −1 parallel to the coast in July 2013, resulting in Ekman transport toward the coast. The most noticeable SLD was measured between Omijima and Mishima, normal to the 250 km rectilinear coastal line. The velocity of the first branch of the Tsushima Warm Current increased to about 50 cm s −1 between Omijima and Mishima from late July to early August. Although the SLD seemed to simultaneously increase and decrease along the Japanese coast with large time scale, the variation in coastal SLD propagated along the Japanese coast, reaching Niigata-nishi in the eastern Japan Sea. The propagation speed in the wide continental shelf of the southern Japan Sea was much higher than that in the narrow eastern shelf, which was consistent with the behavior of continental shelf waves. [ABSTRACT FROM AUTHOR]

Recent eustatic sea level rise (SLR) is one of the most striking manifestations of recent climate change as it directly impacts coastal activities and ecosystems. Although global SLR is well-known, local values differ due to vertical land motion, and changes in atmospheric pressure, ocean currents and temperatures. Although a reliable estimation of local SLR trends is needed to assess coastal zone vulnerabilities and plan adaptation strategies, instrumental records are usually short or sparse, especially in developing countries. Here we show that 210 Pb-dated sedimentary records from mangrove saltmarshes can provide useful decadal records of local SLR trends. We quantified sediment accretion rates in sediment cores from remote mangrove saltmarshes of the Yucatan Peninsula. Best SLR records were observed for cores collected near mean sea level (MSL). During most of the XX century the SLR rate ranged from 1-2 mm yr -1 , increased to a maximum of 4.5 ± 0.6 mm yr -1 and the acceleration was 0.13 mm yr -2 . Assuming either a constant SLR rate or acceleration, by the end of this century MSL level will be 39 cm or 91 cm above the present value. Both coastal infrastructures and ecosystems will be negatively affected by SLR and society will need to adapt relatively fast to the new conditions. [ABSTRACT FROM AUTHOR]

Foraminiferal associations from the Upper Callovian to Lower Kimmeridgian beds of the Makar'yev reference section (Volga Basin, East European Platform) provide insights into contemporaneous palaeoecological, palaeoenvironmental and palaeoceanographic conditions. Foraminiferal associations were studied using semi-quantitative methods, morphogroup analyses and various biodiversity indices, and were compared with different abiotic factors, including transgressive and regressive events, variations in temperature, and the content of total organic carbon (TOC). Analyses of the resulting data show that the Makar'yev section was strongly affected by variations in sea level during Oxfordian time and suggest that the environment was mainly associated with the outer part of the middle sublittoral zone on the outer platform. A regressive event strongly affected the foraminiferal communities at the Early/Middle Oxfordian boundary. This event was followed by a transgressive phase and an increase in water temperature that allowed the opening of a marine pathway and migration of planktonic foraminifera from tropical and sub-boreal latitudes to boreal and sub-arctic latitudes. This phenomenon may explain the increase in foraminiferal biodiversity during the Middle Oxfordian. However, a crisis in microbenthic communities greatly affected foraminifera during the Late Oxfordian. This crisis was probably the result of a combination of two events rather than a single large event: the strong input of organic matter during maximum flooding, and a subsequent second-order regressive event at the transition between the Middle and the Late Oxfordian. This massive injection of organic matter would have increased the quantity of organic carbon as well as decrease the amount of oxygen in bottom water. It ultimately resulted in the development of shallow-water and potentially deep-water infaunal foraminifera, as well as the disappearance of non-adapted taxa from the Late Oxfordian and, particularly, the Kimmeridgian. [ABSTRACT FROM AUTHOR]

Highlights: [•] The Triassic Kangan Formation is composed of carbonate–evaporite sequences. [•] Various anhydrite structure and textures control reservoir quality carbonates. [•] Anhydrites are either intraformational seals or cements plugging pore spaces. [•] Relationships in facies associations/evaporite textures/sea-level fluctuation exist. [•] They show predictable patterns useful for sequence stratigraphic interpretations. [ABSTRACT FROM AUTHOR]

Abstract: The Shuaiba Lagoon is a fossil back-reef, hypersaline small basin located 80km south of Jeddah city on the eastern Red Sea coast, Saudi Arabia. The surface sediments of the lagoon were investigated for their benthic foraminiferal content in order to correlate, in general, with environmental factors such as temperature, salinity, pH, sediment grain size, organic matter and, in particular, with tidal elevations to develop a training set for predicting sea-level changes in the lagoon. Hierarchical cluster analysis divided the benthic foraminifera in the Shuaiba Lagoon into four distinct faunal assemblages. Quinqueloculina cf. Q. limbata (Assemblage 1) and Monalysidium acicularis (Assemblage 2) assemblages dominated the intertidal–high subtidal areas (0.3 to −0.5m, LAT). The Peneroplis planatus–Sorites orbiculus Assemblage 3 occurred abundantly at all subtidal elevations (0 to −1m, LAT), whereas the Quinqueloculina costata–Spiroloculina communis–Elphidium striatopunctatum Assemblage 4 dominated the lowest elevations (<−1.5m, LAT) in the lagoon. Canonical correspondence analysis indicated that the intertidal–high subtidal assemblages were positively correlated with tidal elevations in the Shuaiba Lagoon, consequently, their training set yielded a model predicting sea-level changes with a precision of ±0.16m, but when they were incorporated with the lowest-elevation (low subtidal and below subtidal) assemblages, a wide error (±0.33m) was produced. Abundance distributions of all assemblages were also affected by the other environmental factors such as salinity, organic matter and temperature, but pH was an important controlling factor on many assemblages due, likely, to high algal photosynthesis in algal-dense substrates. The effect of these factors on the predictability of the intertidal–high subtidal training set is unavoidable and it could be compromised by making a model from the different niches of the intertidal–high subtidal area. [Copyright &y& Elsevier]

Reef drowning and backstepping have long been recognised as reef responses to sea-level rise on subsiding margins. During the Late Pleistocene (~500–14 ka) Hawaiian reefs grew in response to rapid subsidence and 120 m 100 kyr sea-level cycles, with recent work on the submerged drowned reefs around the big island of Hawaii, and in other locations from the last deglacial, providing insight into reef development under these conditions. In contrast, reefs of the Early Pleistocene (~1.8–0.8 Ma) remain largely unexplored despite developing in response to significantly different 60–70 m 41 kyr sea-level cycles. The Maui-Nui Complex (MNC — forming the islands of Maui, Molokai, Lanai and Kahoolawe), provides a natural laboratory to study reef evolution throughout this time period as recent data indicate the reefs grew from 1.1 to 0.5 Ma. We use new high resolution bathymetric and backscatter data as well as sub-bottom profiling seismic data and field observations from ROV and submersible dives to make a detailed analysis of reef morphology and structure around the MNC. We focus specifically on the south-central region of the complex that provides the best reef exposure and find that the morphology of the reefs varies both regionally and temporally within this region. Barrier and pinnacle features dominate the steeper margins in the north of the study area whilst broad backstepping of the reefs is observed in the south. Within the Au''au channel in the central region between the islands, closely spaced reef and karst morphology indicates repeated subaerial exposure. We propose that this variation in the morphology and structure of the reefs within the MNC has been controlled by three main factors; the subsidence rate of the complex, the amplitude and period of eustatic sea-level cycles, and the slope and continuity of the basement substrate. We provide a model of reef development within the MNC over the last 1.2 Ma highlighting the effect that the interaction of these factors had on reef morphology. [Copyright &y& Elsevier]