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Interglacials of the Quaternary Period are currently the focus of a great deal of attention within the scientific community. This is primarily because they play a vital role in distinguishing between “natural” and “human” climate change in the current interglacial and in understanding how the Holocene would evolve in the absence of anthropogenic greenhouse warming. In this respect, Marine Isotope Stage 11 (MIS 11, ca 410,000 yr BP) is one of the key interglacial stages of the past 450,000 yr. The pattern of insolation variability that occurs during MIS 11 matches that which occurs in the Holocene more closely than in any other warm stage of the past half a million years. In addition there is now an extensive range of evidence for MIS 11 palaeoclimates and palaeoenvironments from marine, ice core, lacustrine and terrestrial sequences. The aim of this paper is to provide a comprehensive review of the current state of our understanding of MIS 11. This is the first paper to provide a detailed review of MIS 11 that incorporates the wide range of marine, ice core, long lacustrine and terrestrial records that have been generated over the last ten years since the last major overview. Crucially, it is the first review of MIS 11 that incorporates a detailed synthesis of the high-resolution terrestrial sequences of western and central Europe. This paper, therefore, provides a holistic integration of a diverse range of proxies and archives to provide a detailed understanding of the expression of MIS 11 in the Earth system. In particular the review focuses on: (1) the climatic background of MIS 11, (2) the robustness of the identification of MIS 11 in a diverse range of sequences, (3) the climatic structure of MIS 11, (4) the magnitude of warmth that occurred in this warm stage, (5) MIS 11 sea level magnitude and variability, (6) the duration of MIS 11, (7) evidence for abrupt climatic events within the interglacial of MIS 11 and (8) precipitation patterns and trends during this interglacial. The paper concludes by considering how useful MIS 11 is as an analogue for Holocene climates and compares it with other proposed analogues, such as MIS 19, with particular reference to the “early anthropogenic” hypothesis.

The Holocene sediments of the coast of the United Arab Emirates in the southeastern Arabian Gulf are frequently cited in the literature as type examples for analogous assemblages of carbonates, evaporites and siliciclastics throughout the geologic record. This paper is intended as a convenient single source for the description of sediments of this region, providing information on how to reach the classic localities and some of the analogs. The Holocene sediments of the region accumulate over an area that is 500 km long and up to 60 km wide. The sediments collecting offshore are predominantly pelecypod sands mixed with lime and argillaceous mud, with these latter fine sediments increasing as the water deepens. The pelecypod-rich sediments also collect east of Abu Dhabi Island both in the deeper tidal channels between the barrier island lagoons and in deeper portions of the protected lagoons. West of Abu Dhabi Island the shallow water margin is the site of coral reefs and coralgal sands, whereas to the east oolites accumulate on the tidal deltas of channels located between barrier islands. Grapestones accumulate to the lee of the reefs and the oolite shoals where cementation becomes more common. They are particularly common on the less protected shallow water margins of the lagoons west of Abu Dhabi Island. Pelleted lime muds accumulate in the lagoons in the lee of the barrier islands of the eastern Abu Dhabi. Lining the inner shores of the protected lagoons of Abu Dhabi and on other islands to the west are cyano-bacterial mats and mangrove swamps. Landward of these, a prograding north facing shoreline is formed by supratidal salt flats (sabkhas), in which evaporite minerals are accumulating. This paper describes the localities associated with (1) the mangrove swamps of the west side of the Al Dhabaiya peninsula; (2) the indurated cemented carbonate crusts, cyanobacterial flats and sabkha evaporites on the shore of the Khor al Bazam south of Qanatir Island; (3) the reef and oolitic sand flats on the coast just east of Jebel Dhana; and (4) the marine travertine and aragonite coats associated with the beach sediments in a small bay south of Jebel Dhana; and (5) the Sabkha Mutti between Jebel Barakah and Al Sila. Similar sedimentological associations of carbonate and evaporites to those of the Holocene of the United Arab Emirates are to be found in the Tertiary and Mesozoic sedimentary rocks of the immediate subsurface in the Arabian Gulf. Other analogs to this setting include the Paleozoic carbonates of the western USA, Europe, and Asia, Mesozoic carbonates of the Gulf of Mexico, Europe, and Middle East and Tertiary sedimentary rocks in the Middle East.

Vertical movements of the solid surface reflect crustal deformation and mantle deep related phenomena. For Holocene times, coastlines displaced from the present mean sea level are often used, combined with past relative sea levels (RSL) prediction models, to clue the vertical deformational field. Along the coast from south-western Turkey until Israel and Cyprus, a certain amount of good quality data is already published, leaving only a gap where data are absent along the Central Anatolian Plateau (CAP) coast. Based on new field observations along with this sector, between Adalia and Adana (Mersin, southern Turkey), together with AMS 14C dating, the gap is filled, allowing to describe an overall frame made by vertical differential movements along the Eastern Mediterranean coast. Most recent Glacial Isostatic Adjustments (GIA) models have been used to remove the glacio-hydro isostatic component of the RSL. Different solutions from ICE-6G(VM5a) and ICE-7G(VM7) models (developed by W.R. Peltier and co-workers, Toronto University), as also a solution from the GIA model progressively developed by K. Lambeck and collaborators at the Australian National University, have been applied on 201 middle-to-late Holocene markers of RSL. Both GIA models have been implemented within the numerical Sea level Equation solver SELEN4.Tectonic velocity has been therefore calculated. Starting from southwestern Turkey, subsidence has been found within the range between -0.91 mm/yr and -2.15 mm/yr confirming values from previous works. Velocities from the new markers along the CAP coast are positive ranging between 1.01 and 1.65 mm/yr. These two first blocks are separated by a sharp velocity contact, occurring along the complex fault zone of the Isparta Angle. Such values for the CAP margin were expected as recently published papers report high vertical velocities for a Middle to Late Pleistocene uplift event. Moving to the east, velocities are also positive, within 0.3-0.6 mm/yr, along the coast between the Hatay Gulf and southern Lebanon. The spiked profile of the Lebanese sector is likely due to co-seismic deformations along the Lebanese Restraining Bend faults (LRB). To the south, the Israeli coast is instead showing stability according to some unique RSL markers named piscinae while other markers indicate slow subsidence. Hence another velocity jump of at least 0.5 mm/yr is recognizable between Israel and Lebanon: it is probably associated with already known brittle structures. In northern Cyprus, the only Holocene sea-level marker confirms the almost zero vertical velocity values already obtained for the MIS 5e marine terrace. Therefore, a vertical velocity jump occurs between stable Cyprus and the uplifting CAP southern margin, although they are placed on the same overriding plate of the subduction system. High-angle normal faults at the northern margin of the Adana-Cilicia Basin could explain these different vertical velocity fields. These results depict a complex frame of wide independently moving crustal blocks where kinematic separation occurs along well-known regional fault zones. Driving causes of the block movements could be related either to regional tectonics, as it probably is for the LRB coast, or to mantle dynamics, for the uplifting Turkish sector where deeper processes should be considered.

Understanding of complex sedimentary records formed by transgressive systems is critical for hydrocarbon exploration and exploitation, and carbon capture and storage. This paper discusses the facies proportions and preservation of the Last Interglacial and Holocene transgressive systems tracts in the Netherlands and their applicability as a North Sea Basin analogue for the Early Jurassic Are Formation in the Norwegian offshore. New and existing data from both (sub-)modern transgressive Rhine records were thoroughly reviewed from a sequence stratigraphic perspective, before volumetrics were calculated and longitudinal trends quantified at reservoir scale. Large differences between the Last Interglacial and Holocene transgressive systems were found: the volume of fluvial deposits is almost six times larger and the volume of organics nearly twenty times larger in the Holocene record than in the Last Interglacial record. In contrast, the volume of estuarine deposits in the Holocene record is only half of that of the Last Interglacial record. Remarkably, both records show similar averaged sediment-trapping rates of 8–9 km3/ka. Initial valley configuration and relative sea-level rise-rates during both transgressions were key controls on the volume and spatial arrangement of the transgressive deposits. Relative sea-level fall and river avulsion determined what amount of sediment was left preserved after completion of one interglacial-glacial cycle. Comparison of the Late Quaternary Rhine records with the Late Triassic to Early Jurassic Are Formation in the Heidrun Field off mid-Norway, showed the potential of the (sub-)modern Rhine records as analogues for ancient stratigraphic records. Especially the transgressive Rhine sequence from the Last Interglacial provided remarkable similarities in facies proportions, preservability, autogenic processes and controlling forcings, ranging from metre-scale vertical-successions to kilometre-scale field-wide events for parts of the Are Formation. The side-by-side availability of the truncated Last Interglacial and (still) fully preserved Holocene transgressive system proved to be an excellent natural laboratory to study the stratigraphic architecture and assess depositional trends and preservability over longer time scales (>100 ka). It nevertheless demonstrates that no ‘one-size-fits-all’ analogue exists, but that various other analogues are needed to solve the complex puzzle which the Are Formation resembles.

Studies of mud clinoforms in marine environments have documented a wide diversity in the behavior of depositional systems on continental margins with different sedimentary dynamics and spatiotemporal characteristics. The mud clinoform associated with the Bohia Strait off the Shandong Peninsula has attracted the attention of marine geologists and sedimentologists. After systematically reviewing the climatology, oceanography, and sedimentology as well as postglacial sea level change on the East China shelf and the changes in the strength of the East Asian winter monsoon, the aim of this paper is to provide a comprehensive explanation for the evolution of the clinoform and to establish a model of a tidal current-controlled mud clinoform on the seaward side of a tidal inlet. The Bohai Strait is a large tidal inlet linking the Bohai Sea (a large bay) and the Yellow Sea (an open sea). The Yellow River delivers large amounts of fine-grained sediments to the southern Bohai Sea. Under the action of the East Asian monsoon, the speed and duration of ebb currents are higher and longer than those of the flood currents in the southern Bohai Strait. The stronger NNW wind in winter causes more powerful waves on the southern Bohai Sea, inducing high suspended sediment concentrations (SSC). These suspended sediments are transported by ebb currents from the Bohai Sea to the Yellow Sea through the southern Bohai Strait, particularly in winter, and then deposited on the seaward side of the strait, forming the ebb-tidal clinoform off the Shandong Peninsula. The evolution of the ebb-tidal clinoform is controlled mainly by historical changes in the strength of the East Asian winter monsoon and the spatial extent of the Bohai Sea. The clinoform has been accumulating since 9600 cal BP; it formed mainly from 8200 to 5000 cal BP, when a strong East Asian winter monsoon produced relatively strong ebb currents with high SSC in the southern Bohai Strait, whilst the extent of the Bohai Sea was large. The ebb currents from 9600 to 8200 cal a BP and during the last 5000 years were comparatively weak, primarily as a result of the small area of the Bohai Sea in the former time interval and a weak East Asian winter monsoon in the latter time interval. These changes in the area of the Bohai Sea and monsoon strength also caused the deposition rates within this clinoform to differ from the rates during the period 8200 to 5000 cal BP, i.e. when the area of the Bohai Sea was large and the East Asian winter monsoon was relatively strong. From 8200 to 5000 cal BP, the deposition rates were 4.4–5.8 times the rates during the past 5000 years. Whilst it has been argued that the development of the clinoform could be associated with the evolution of the Yellow River delta, this hypothesis is not consistent with the ages of these features. A significant portion of the clinoform formed before 7000 cal BP, the point at which delta development was initiated. The Yellow River delta on the west coast of the Bohai Sea and the clinoform off the Shandong Peninsula are not coeval and do not belong to a compound-clinoform system. It is concluded that the clinoform off the Shandong Peninsula is substantially a large mud ebb-tidal delta on the seaward side of the Bohai Strait. The clinoform on the seaward side of the Bohai Strait and the flood tidal sand ridges and sand sheet on the landward side of the Bohai Strait constitute a complete tidal depositional system on both sides of this large inlet. This new insight may enhance the understanding of the formation of mud clinoforms on other shelf environments and facilitate the analysis of tidal zone palaeofacies.

Fluvial archives, in particular, late glacial to Holocene floodplain records may provide valuable information regarding past environmental conditions and stages of landscape evolution. In view of the high significance of floodplain dynamics for the development of entire landscapes, the number of studies that have been performed on floodplain sediments remains comparatively low, especially regarding the Western Mediterranean region. However, one of the reasons could be seen in the high complexity and diversity of processes and factors that control and influence fluvial activity that often hampers a straightforward interpretation of floodplain dynamics. Therefore, a basic demand on fluvial archive research is to address the complexity of the factors that control the characteristics of fluvial sequences in order to provide a robust basis for their interpretation. As a starting-point for discussion this paper aims to give an overview of fluvial dynamic patterns in the Western Mediterranean for the last 15 ka in order to examine their relevance for palaeoenvironmental reconstructions. The basis for this is provided by previous investigations on four different river systems in Spain and northern Africa the results of which are herein synthesized in order to propose a regional Late Pleistocene and Holocene fluvial history for the Western Mediterranean realm. Basic results are related to alluvial floodplain deposits and visible features within them such as alluvial soils, incision marks and aggradation phenomena. Since fluvial systems are open systems, we discuss our findings against the background of different influencing factors that could modify fluvial architecture and may restrict palaeoenvironmental reconstructions. A more comprehensive interpretation focuses on signals that are common to each of the studied river systems. In this respect, we critically discuss the customary nature of cumulative probability functions for the identification of regional flooding episodes and point out the benefits of a stratigraphy-supported approach for characterizing regional floodplain dynamics. Finally, three alluvial soil formation periods were found in all settings: a first phase after 15 ka, ending with the Younger-Dryas Event; a second one from 7 to 5 ka with a break between 6.5 and 5.5 ka, and a third phase between 3 and 2 ka. These soil formation periods were interrupted and framed by fluvial dynamic phases accompanied by channel aggradation, floodplain deposition, floodplain erosion and/or river incision. In particular, after 5 ka, around 1.6 and at 1 ka, and during the Little Ice Age (LIA) floodplain aggradation affected river systems in Iberia and northern Africa as well. A cautious assessment of these results and extensive comparisons with secondary archive information prompts us to relate the aggradation periods with climate forcing by means of a supra-regional aridification that effected large areas of the Western Mediterranean. In contrast, the three mentioned soil formation periods can be linked with landscape stability, most probably triggered by favorable climate conditions in the Western Mediterranean. Apart from these large-scale patterns we discuss the reliability of information emerging from floodplain records against the background of individualistic river behavior and self-organization. Regarding future work we want to emphasize the great potential of yet rarely applied system-oriented approaches that also attach importance to sub-catchment dynamics as a link between catchment slopes and the main river floodplain.

In this review paper, we identify and address key uncertainties related to four local and global controls of Holocene northern peatland carbon stocks and fluxes. First, we provide up-to-date estimates of the current northern peatland area (3.2 M km 2 ) and propose a novel approach to reconstruct changes in the northern peatland area over time (Section 2). Second, we review the key methods and models that have been used to quantify total carbon stocks and methane emissions over time at the hemispheric scale, and offer new research directions to improve these calculations (Section 3). Our main proposed improvement relates to allocating different carbon stock and emission values for each of the two dominant vegetation assemblages (sedge and brown moss-dominated vs. Sphagnum -dominated peat). Third, we discuss and quantify the importance of basin heterogeneity in estimating peat volume at the local scale (Section 4.1). We also highlight the importance of age model selection when reconstructing carbon accumulation rates from a peat core (Section 4.2). Lastly, we introduce the role of biogeomorphological agents such as beaver activity in controlling carbon dynamics (Section 5.1) and review the newest research related to permafrost thaw (Section 5.2) and peat fire (Section 5.3) under climate change. Overall, this review summarizes new information from a broad range of peat-carbon studies, provides novel analysis of hemispheric-scale paleo datasets, and proposes new insights on how to translate peat-core data into carbon fluxes. It also identifies critical data gaps and research priorities, and many ways to consider and address them.

This paper presents a review of Late Quaternary climatic changes and glacier variability in the Himalaya and East Africa, focusing on the role of Indian Summer Monsoon (ISM), East African monsoon, and Westerlies monsoons. Multi-proxy studies which are based on five different archives (lakes, peat bogs, speleothems, marine sediments, and ice cores) including sixty-six records from India and nearby regions, particularly in the Himalaya and in addition to six archives from the equatorial Eastern part of Africa encompasses with high-resolution published and unpublished records for the last 50 ka BP. The proxy data is discussed towards REMO-ESM model Coupled Model Intercomprasion Project phase 5 (CMIP5 Project) results. Our results indicate that both Western Himalaya and East Africa had undergone mega-droughts from ~17.0–15.0 ka BP, and precipitation had increased during the Early Holocene (10.0–7.0 Ka BP) during the time span when the Westerlies dominated regions. The model results suggest that the Westerlies monsoon has significantly contributed to the Northwestern Himalaya and somewhat to a lesser degree to the Western Himalaya and lower solar insolation in the winters did support the glacier advance during the LGM. The time series from the proxy data are compared with glacier fluctuations in different valleys to understand the response of the aforementioned monsoon system including other forcing factors which drive these variabilities. The review results indicate that the Westerlies was the main driver of the climate and glacier fluctuations in Northwestern Himalaya during the Late Quaternary. The Early and Late Holocene glacier fluctuation was mainly controlled by Westerlies precipitation in Northwestern Himalaya and the ISM controlled the glacier fluctuations in the Western Himalaya during Late Quaternary.

This paper reviews the variable features of coastal tsunamis caused by offshore active faults along the eastern margin of the Japan Sea (EMJS) based on the historical records and modern observations of earthquakes and tsunamis. Tsunami deposits discovered along the EMJS coast were also introduced and categorized depending on their sedimentary environments. The offshore active faults, which are densely distributed along the EMJS and generate tsunamis, are originated from the opening of the Japan Sea back-arc basin during the late Oligocene to Miocene period. The magnitudes of the earthquakes that caused large tsunamis in the EMJS were under 8.0. The size of the fault plane (approximately equal to the tsunami source area) was approximately 10 × 100 and several tens of kilometers in length. The slip distance of the reverse-type faults was less than 20 m. The sedimentary characteristics and depositional processes of tsunami deposits were obtained from deposits in various environments, such as coastal lowlands, marine terraces, coastal lagoons, and inland ponds. Certain unique approaches used to identify tsunami deposits were reviewed, such as gravel layers that intercalate inorganic soils, and a Holocene marine terrace, dinoflagellate cysts, and foraminiferal linings, which are potentially derived from the sea, and chemical features (e.g., the Ca2+/Mg2+ ratio) as indicators of seawater inflow into a coastal lagoon. The spatial distribution and recurrence of earthquakes and tsunamis in the EMJS were found based on previous paleo-tsunami studies. The difference between tsunami deposits caused by offshore active faults and those by megathrust earthquakes only manifests itself in the horizontal and vertical directions, but not in the sedimentary environments and structures. The data thus inferred can be used for the estimation of offshore active fault models and validation of previous tsunami disaster reconstructions in the future.

This paper aims to achieve an improved understanding of the long-term change trends of precipitation δD and δ 18 O values (δD p and δ 18 O p ) in the Asian monsoonal region and their relationship with the corresponding humidity trends during the Holocene. To do this we first review the observed modern spatial pattern of summer precipitation distribution in the East Asian summer monsoon (EASM) region under different EASM intensities, and the relationship between modern observed δ 18 O p values and corresponding precipitation amounts on monthly and inter-annual timescales in the EASM and Indian summer monsoon (ISM) regions. Second, we compare Holocene lacustrine and marine compound-specific hydrogen isotopic records of n -alkanes/ n -alkanoic acid (δD n ), lacustrine authigenic carbonate and cave stalagmite oxygen isotopic records (δ 18 O c and δ 18 O s ) from the Asian monsoonal region, all of which are closely related to δD p and δ 18 O p variations. The results demonstrate that in both the ISM and EASM regions, all of these isotopic records exhibit roughly similar long-term characteristics, i.e. they were all more negative during the early-Holocene and early mid-Holocene (ca. 11–6 ka B.P.; B.P. means before present, present = 1950 AD), and then became more positive towards the late-Holocene. Third, we compare representative paleo-humidity records from the Asian monsoonal region; the results confirm that, in the ISM region, a humid interval occurred in the early-Holocene and early mid-Holocene (ca. 11–6 ka B.P.) and subsequently the climate became more arid towards the late-Holocene. This indicates an enhanced ISM during the early-Holocene and early mid-Holocene (ca. 11–6 ka B.P.), and an ISM of decreasing intensity towards the late-Holocene. On a Holocene orbital scale, both δ 18 O p and δD p appear to be controlled by an “amount effect” in the ISM region, consistent with the region's inter-annual modern δ 18 O p data. This evidence indicates that both δ 18 O p and δD p paleo-records are significantly related to paleo-humidity in the ISM region. In contrast, Holocene humidity variations in the EASM region exhibit clear spatial differences: a humid mid-Holocene interval (ca. 8–3 ka B.P.) occurred in southern and northern China, but an arid interval from ca. 7–3 ka B.P. occurred in central China, in the middle reaches of the Yangtze River. Based on precipitation distribution patterns under different EASM intensities in the EASM region over the past few decades, we conclude that EASM intensity was enhanced during the mid-Holocene (ca. 8–3 ka B.P.). Relative to the ISM intensity, the response of EASM intensity to summer insolation was relatively slow. In the EASM region the relationship between climate and δ 18 O p and δD p is more complex, consistent with analyses of regional inter-annual modern δ 18 O p data. This evidence demonstrates that both δ 18 O p and δD p paleo-records cannot be used directly as paleo-humidity (i.e. precipitation amount or EASM intensity) indicators in the EASM region. Further comparison and analyses demonstrate that the coupled variations in west–east Equatorial Pacific temperature gradients and the West Pacific subtropical high (WPSH) played an important role in determining EASM intensity during the Holocene.

Natural chemical tracers contained in moisture within unsaturated zone (USZ) sediments have very significant potential as a novel archive of past climate and palaeoenvironmental conditions in dryland environments. However, this potential has yet to be fully realised. The tracer signature is established in the near-surface zone, with evapotranspiration processes enriching the concentration inherited from input from atmospheric deposition (predominantly rainfall). This pore-moisture tracer signature then moves vertically through the USZ sediments toward the water table, producing a hydrostratigraphy that, with increasing depth, records changes to the moisture balance at the surface through time. The small fluxes of water through the USZ in dryland climates means that this hydrostratigraphy approach is particularly valuable in these environments for providing climate records longer than the instrumental data period. This paper sets out the current state of the art in the use of the USZ as an archive. We explain the nature of the USZ, the basis of the tracer technique and also the field and sampling methodologies employed. Examples of application worldwide by broad geographic region are also evaluated. This shows that the USZ hydrostratigraphy approach can be used across three key timescales: (i) decadal to multi-decadal resolution records covering hundreds of years that provide information about recent climate fluctuations and patterns of land-use change; (ii) multi-decadal through to millennial scale length records which may record wetter and drier events down to decadal scale resolution and (iii) Last Interglacial through to the Holocene records of lower resolution that indicate broad shifts over multi-millennial timescales. We also explore the questions and challenges surrounding the depositional flux of tracer inputs and the extent to which infiltration is non-uniform, before setting the agenda for their future potential use alongside related proxies for palaeohydrology.

The Mississippi River fluvial–marine sediment-dispersal system (MRS) has become the focus of renewed research during the past decade, driven by the recognition that the channel, alluvial valley, delta, and offshore regions are critical components of North American economic and ecological networks. This renaissance follows and builds on over a century of intense engineering and geological study, and was sparked by the catastrophic Gulf of Mexico 2005 hurricane season, the 2010 Deep Water Horizon oil spill, and the newly recognized utility of source-to-sink concepts in hydrocarbon exploration and production. With this paper, we consider influences on the MRS over Neogene timescales, integrate fluvial and marine processes with the valley to shelf to deepwater regions, discuss MRS evolution through the late Pleistocene and Holocene, and conclude with an evaluation of Anthropocene MRS morphodynamics and source-to-sink connectivity in a time of profound human alteration of the system. In doing so, we evaluate the effects of tectonic, climatic, and anthropogenic influences on the MRS over multiple timescales. The Holocene MRS exhibits autogenic process-response at multiple spatial and temporal scales, from terrestrial catchment to marine basin. There is also ample evidence for allogenic influence, if not outright control, on these same morphodynamic phenomena that are often considered hallmarks of autogenesis in sedimentary systems. Prime examples include episodes of enhanced Holocene flooding that likely triggered avulsion, crevassing, and lobe-switching events at subdelta to delta scales. The modern locus of the Mississippi fluvial axis and shelf–slope–fan complex was established by Neogene crustal dynamics that steered sediment supply. Dominant Miocene sediment supply shifted west to east, due to regional subsidence in the Rockies. Then, drier conditions inhibited sediment delivery from the Rocky Mountains, and Appalachian epeirogenic uplift combined with wetter conditions to enhance sediment delivery from the Appalachians. Climatic influences came to the forefront during Pleistocene glacial–interglacial cycles. The fluvial system rapidly responded to sea-level rises and falls with rapid and extensive floodplain aggradation and fluvial knickpoint migration, respectively. More dramatically, meltwater flood episodes spanning decades to centuries were powerful agents of geomorphic sculpting and source-to-sink connectivity from the ice edge to the deepest marine basin. Differential sediment loading from alluvial valley to slope extending from Cretaceous to present time drove salt-tectonic motions, which provided additional morphodynamic complexity, steered deep-sea sediment delivery, diverted and closed canyons, and contributed to modern slope geometry. Despite the best efforts from generations of engineers, the leveed, gated, and dammed Mississippi still demonstrates the same tendency for self-regulation that confronted 19th century engineers. This is most apparent in the bed-level aggradation and scour associated with changes in sediment cover and stream power in river channels, and in the upstream migration of channel depocenters and fluvial and sediment outlets at the expense of downstream flow, that will ultimately lead to delta backstepping. Like other source-to-sink systems, upstream control of sediment supply is impacting downstream morphology. Even within the strait-jacketed confines of the modern flood control system, the Mississippi River still retains some independence.

Understanding the natural variability of the Earth's climate system and accurately identifying potential anthropogenic influences requires long term, geographically distributed records of key climate indicators, such as temperature and precipitation that extend prior to the last 400. years of the Holocene. Reef corals provide an excellent source of high resolution climate records, and importantly represent the tropical marine environment where palaeoclimate data are urgently required. Recent decades have seen significant improvement in our understanding of coral biomineralisation, the associated uptake of geochemical proxies and methods of identifying and understanding the effects of both early and late, post depositional diagenetic alteration. These processes all have significant implications for interpreting geochemical proxies relevant to palaeoclimatic reconstructions. This paper reviews the current 'state of the art' in terms of coral based palaeoclimate reconstructions and highlights a key remaining problem. The majority of coral based palaeoclimate research has been derived from massive colonies of Porites. However, massive Porites are not globally abundant and may not provide material of a particular age of interest in those regions where they are present. Therefore, there is great potential for alternate coral genera to act as complimentary climate archives. While it remains critical to consider five key factors - vital effects, differential growth morphologies, geochemical heterogeneity in the skeletal ultrastructure, transfer equation selection and diagenetic screening of skeletal material - in order to allow the highest level of accuracy in coral palaeoclimate reconstructions, it is also important to develop alternate taxa for palaeoclimate studies in regions where Porites colonies are absent or rare. Currently as many as nine genera other than Porites have proven at least limited utility in palaeothermometry, most of which are found in the Atlantic/Caribbean region where massive Porites do not exist. Even branching taxa such as Acropora have significant potential to preserve environmental archives. Increasing this capability will greatly expand the number of potential geochemical archives available for longer term temporal records of palaeoclimate.

China's Badain Jaran Sand Sea features the tallest dunes on Earth and a unique mega-dune–lake landscape. It had been explored little until the 1990s, though early scientific explorations surrounding the sand sea had begun by the early 20th century. Heated debates now focus on the desert environment, and particularly how the mega-dunes and desert lakes develop and evolve. This paper reviews the status of these debates and summarizes the supporting evidences. The environmental research mainly concerns formation and evolution of the sand sea, and its relationship with climate change. The proposed formation time ranges from the Early Pleistocene to the Holocene. Opinions vary about climate change on different time scales. The reconstructed climate change history is shorter than the sand sea's history, with the longest record extending to the Late Pleistocene. The mega-dune research focuses on sediments, dune morphology, and formation processes. It remains unclear whether the mega-dunes result primarily from wind action, control by the underlying topography, or groundwater maintenance. The sources of lake water are also debated, but there are four main hypotheses: atmospheric precipitation, groundwater from nearby areas, precipitation and snowmelt in remote areas such as the Qilian Mountains and the Qinghai–Tibetan Plateau, or paleowater that formed during past periods of wet climate. We believe that the sand sea deserves further study in terms of its dune geomorphology, evolution, and hydrology, and their responses to climate change. Meteorological and hydrological observations and monitoring in the sand sea are particularly necessary.

Holocene reconstructions of relative sea-level (RSL) and environmental change in the coastal zone have become progressively more numerous since the importance of assessing possible future sea-level rises has become apparent. Traditionally this has been achieved using a combination of biological and physical indicators (e.g. pollen, diatoms, foraminifera, grain size, etc.). In some circumstances, microfossils can be rare or absent from Holocene sediments and in these cases carbon isotope ratios (δ13C) and organic carbon to total nitrogen ratios (C/N) can be used because they have the potential to provide information as to the origin of organic material preserved in coastal environments. The distinction in δ13C and C/N of the various sources of carbon to estuarine sediments has led to its wide use as a tracer of carbon pathways and storage in estuaries. More recently these techniques have been applied to Holocene sediments to decipher changes in palaeocoastal environments and thus position relative to sea-level and/or palaeoriver discharge, which have direct relevance to palaeoclimate. This paper reviews the studies that have utilised this technique and explores examples from a wide range of coastal environments (saltmarshes, estuaries, lagoons, isolation basins and fjords). It also discusses the potential alteration of geochemical signatures as a result of decompositional processes. Organic matter decomposition has been shown to change sediment δ13C and C/N values and thus an understanding of the processes involved is necessary in order to have confidence in the palaeoenvironmental interpretation of Holocene δ13C and C/N. Decompositional shifts in C/N, and particularly δ13C, can occur over a relatively short time-period, however it is the direction of change in δ13C and C/N, rather than absolute values, that is key for interpreting changes in relative sea-level and thus such changes are commonly preserved.

This paper reviews the history of the woolly mammoth (Mammuthus primigenius Blum.) in Siberia and adjacent northern Asia. The particular emphases are the chronology and environment of mammoth existence and extinction, based on about 530 radiocarbon dates from about 230 localities with mammoth remains and palaeoenvironmental records of the last 50,000 years. Until ca. 12,000 radiocarbon years ago (BP), mammoths inhabited all of northern Asia, from the High Arctic to southern Siberia and northeastern China. Since ca. 12,000 BP, mammoth disappeared from major parts of Siberia and adjacent northern Asia, and survived mainly in the Arctic regions of Siberia, north of 69° northern latitude. However, recently, it was found that some mammoth populations continued to exist in central and southern Western Siberia until ca. 11,100–10,200 BP. ‘Normal’ size mammoths became extinct in mainland Siberia at the Pleistocene–Holocene boundary, ca. 9700 BP. On Wrangel Island in the High Arctic, small-sized mammoths survived into the Middle–Late Holocene, ca. 7700–3700 BP. Compared with previous studies, it is now possible to reveal the complex nature of the process of final mammoth extinction in Siberia, with some small populations surviving outside of the Arctic until ca. 10,000 BP. The extinction of mammoth was most probably caused by a combination of factors, such as global warming in the Late Glacial (since ca. 15,000 BP) and the disintegration of landscapes suitable for mammoths throughout the Upper Pleistocene, such as light forests with vast open spaces occupied by meadows and forest tundra. The expansion of forest vegetation after the Last Glacial Maximum in Siberia, including its northeastern part, created unsuitable habitats for herbivorous megafauna, especially for mammoths. However, the Holocene environment of Wrangel Island was not of ‘glacial’ type and this requires further studies. The relationship between mammoths and Upper Palaeolithic humans is also considered. The role of humans in the process of mammoth extinction was of secondary importance. The lack of direct evidences of mammoth hunting limits the estimation of its role in Upper Palaeolithic human subsistence. Siberia is undoubtedly the area where the final extinction of mammoth occurred, and the future study of this process is important to understand the patterns of Pleistocene megafaunal extinction in the Northern Hemisphere.

Several broad-scale climatic oscillations during the last deglaciation are well documented in regions around the North Atlantic Ocean. This paper reviews empirical evidence for these deglacial climatic oscillations from non-coastal North America and discusses implications for testing climatic simulations and for understanding the cause and transmittal mechanisms. Paleoclimatic interpretation of oxygen-isotope records from several small sites in the eastern Great Lakes region indicates a classic deglacial climatic sequence that is comparable with records from Europe and Greenland. The climatic events as interpreted from Crawford Lake oxygen isotopes include the Bolling–Allerod (BOA) warming at ∼12,700 14C BP, a warm BOA at ∼12,500–10,920 14C BP, an intra-Allerod cold period shortly before 11,000 14C BP, a cold Younger Dryas (YD) climate reversal at 10,920–10,000 14C BP, the Holocene warming at 10,000 14C BP, a brief Preboreal Oscillation (PB) at 9650 14C BP, and an early-Holocene cold event at 7500 14C BP (8200 cal BP). Some of these events were also evident from changes in upland and aquatic vegetation and sediment lithology. The pronounced YD climatic reversal has been documented from pollen records along the ecotones at this time and from glacier readvances in the Great Lakes region. Along the Rocky Mountains from Alberta to Colorado, the YD event is indicated by alpine glacier advance and/or shift in timberline vegetation. In Minnesota and upper New York, early-Holocene climatic instability is also suggested by oxygen-isotope records and/or varve thickness. The regional variations in evidence for the YD and other events in North America suggest that climatic oscillations may have different expressions in paleo-records, depending on geographic location and characteristics of a particular site. The extent and magnitude of these climatic oscillations across North America suggest that these oscillations are an expression of climatic change that was probably widespread rather than locally induced by a nearby glacier. The location of these sites implies that climatic signals were likely carried over the Northern Hemisphere through the atmosphere, as indicated by general circulation models. We hypothesize that the lack of evidence for a cold YD in interior North America west of the Great Lakes region and east of the Rocky Mountains was caused by the trapping of cold arctic air mass north of the Laurentide ice sheet and by uninterrupted northward expansion of warm Caribbean air; this strongly contrasted climate also produced non-analogous biological assemblages.