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The Marmara region (NW Turkey) has a transitional vegetation and climate between the Mediterranean one and the Euxinian one. For the last Interglacial period or Eemian and following the two Saint-Germain Interstadials (i.e. c. MIS 5), as well and the previous glacial, the Saalian, no vegetation or climate information is available yet. Here we provide the results of the pollen analysis of two sediment cores taken from the Sea of Marmara. We focus on the period below a major erosion horizon, i.e. the red-H1 seismic horizon, which corresponds to the last Interglacial and a large part of the previous glacial period. A palaeoclimatic reconstruction inferred from pollen assemblages is also proposed here. Based on geochemistry that allows inter-core comparison and on a succession of warm and cold phases derived by pollen analysis, a nearly complete sequence from the Saalian Glacial period (c. MIS 6) to the Saint-Germain II Interstadial (MIS 5a) was obtained, despite the occurrence of hiatuses corresponding often to lowstands. The Pterocarya extinction has been traced from MIS 7 in Italy to Saint-Germain I Interstadial (c. MIS 5c) in the eastern Sea of Marmara, showing a progressive retreat from west to east until the Black Sea region, where it is still present nowadays. The climatic changes reconstructed for the Eemian Interglacial (or c. MIS 5e) are characterised by warmer temperature and a slightly drier climate than at present, at its peak. This pattern is in agreement with the Ohrid climate pattern, in the Balkans. In the Marmara region, this is reflecting a shift of the Mediterranean climate towards the NE and a reduction of the Euxinian vegetation. • Pollen analyses of last Interglacial and previous Glacial in Sea of Marmara. • Progressive Pterocarya extinction from MIS7 in S. Europe to MIS5c in Sea of Marmara. • Reduction of Euxinian vegetation and extension of the Mediterranean one during Eemian. • Eemian warmer and slightly drier than present climate. [ABSTRACT FROM AUTHOR]

A revision of the data used to build the Caspian Sea level curve over the last 2200 years BP has been made based on a combination of geological and archaeo-historical data, using only those for which sufficient metadata were available. This compilation is completed by new sedimentological and palynological data from the south-east corner of the Caspian Sea, especially close to the known termini of the Sasanian Gorgan and Tammisheh Walls. A new calibration of the radiocarbon dates was used, i.e. with a freshwater offset reservoir of 351 ± 33 years. A literature survey of the Derbent lowstand indicated that this term has different definitions, depending on authors; it is thus to be used with caution. Here we therefore prefer to distinguish the mid-Sasanian lowstand and the later Medieval moderate lowstand. The "2600 years BP highstand" has not been found, mostly due to the calibration or recalibration of the datapoints used; data are indeed lacking at that time. Instead, a younger Parthian highstand (around 50 BC–50 AD) is clearly defined. The maximal amplitude and speed of change of the Caspian Sea level were respectively of >15 m and 14 cm per year. Compared to last century, the latter rate is 25% higher, but the amplitude is more than five times larger. The climatic causes of the Caspian Sea level changes are discussed. It is far from a simple case of temperature forcing; temperature forcing may result in several effects, that may impact the Caspian Sea level variations in opposite ways. Moreover, human intervention on river diversion and natural hazards were likely, for several time periods. • Revision of Caspian Sea level datapoints over last 2200 years with new points • Geological and archaeo-historical dara with new calibration of radiocarbon dates • Derbent lowstand & 2600 yr BP highstand revised, and newly named Parthian highstand • Ambiguous forcing by temperature, re-inforced role of river diversions • Amplitude and rate of changes both larger than in the last century [ABSTRACT FROM AUTHOR]

Abstract: Dinoflagellate cyst assemblages were analysed in four short sediment cores collected in the south Basin of the Caspian Sea for assessing environmental changes over the last few millennia. Two of these cores were dated by radionuclides. The sedimentation rate of one of them was very high, in the order of 20 mm per year. The interpretation of the four sequences is supported by a collection of 27 lagoonal or marine surface sediment samples. A sharp increase in the concentration of the dinocyst occurs after 1967, especially owing to Lingulodinium machaerophorum. Considering nine other cores covering parts or the whole of Holocene, it became clear that this species started to develop in the Caspian Sea only during the last three millennia. By analysing instrumental data and collating existing reconstructions of sea level changes over the last decades, we show that the main forcing for the recent increase of L. machaerophorum percentages and concentration is global climate change, especially sea surface temperature increase. Sea level fluctuations likely only have a minor impact. We argue that the recent increase in L. machaerophorum indicates that the Caspian Sea clearly is in the Anthropocene. [Copyright &y& Elsevier]

Abstract: The vegetation and the climatic context in which the first hominins entered and dispersed in Europe during the Early Pleistocene are reconstructed, using literature review and a new climatic simulation. Both in situ fauna and in situ pollen at the twelve early hominin sites under consideration indicate the occurrence of open landscapes: grasslands or forested steppes. The presence of ancient hominins (Homo of the erectus group) in Europe is only possible at the transition from glacial to interglacial periods, the full glacial being too cold for them and the transition interglacial to glacial too forested. Glacial–interglacial cycles forced by obliquity showed paralleled vegetation successions, which repeated c. 42 times during the course of the Early Pleistocene (2.58–0.78 Ma), providing 42 narrow windows of opportunity for hominins to disperse into Europe. The climatic conditions of this Early Pleistocene vegetation at glacial-interglacial transitions are compared with a climatic simulation for 9 ka ago without ice sheet, as this time period is so far the best analogue available. The climate at the beginning of the present interglacial displayed a stronger seasonality than now. Forest cover would not have been hampered though, clearly indicating that other factors linked to refugial location and soils leave this period relatively free of forests. Similar situations with an offset between climate and vegetation at the beginning of interglacials repeated themselves throughout the Quaternary and benefitted the early hominins when colonising Europe. The duration of this open phase of vegetation at the glacial–interglacial transition was long enough to allow colonisation from the Levant to the Atlantic. The twelve sites fall within rather narrow ranges of summer precipitation and temperature of the coldest month, suggesting the hominins had only a very low tolerance to climate variability. [Copyright &y& Elsevier]

Abstract: The Dead Sea sediment holds the archives of a complex relationship between ever-changing nature and ancient civilisations. Here the detailed pollen analyses of core DS7-1SC (off-Ein-Gedi) are presented for the first time. The record covers the last 2500 years. The facies changes from halite (when no freshwater flows in the Dead Sea) to laminites (when rainfall provides sufficient inflow for the Jordan and subsidiary rivers) a couple of times through the record. The pollen diagram (supported by the facies change) shows a wetter Roman-Byzantine period, which allowed intensive arboriculture and a wetter period at the end of the XIXth and beginning of the XXth centuries, the latter in good relation with historical and instrumental data. Based on radiocarbon chronologies on several pollen diagrams along the western Dead Sea shore, the transition to drier climates and the transition to pastoralism are suggested to take place between a few decades before the Islamic period and close to this transition. A high-resolution palynological study of the individual laminae forming the laminites (aragonite and gypsum in the summer versus detritics in winter) confirms the seasonal character of the laminae, but throws a note of caution as for their regular annual character. [Copyright &y& Elsevier]

Arid Central Asia is at the border between the prevailing Westerlies and monsoonal climates. Lake Issyk-Kul, a large mountain lake, and its sediment record are key to reconstructing complex interactions between these two major climatic systems over time. We present for the first time sedimentological (magnetic susceptibility, CaCO 3 , δ13C and δ18O values of benthic ostracods and fine-grain carbonates) and palynological investigations of a sequence covering the last 12,750 years, with additionally some proxies at a lower resolution above 3590 years ago. From 12,750 until 10,000 years ago, vegetation reflects desert to semi-desert conditions around the lake. Soil erosion is intensive as reconstructed from high Glomus percentages and high magnetic susceptibility. The values of fine-grain carbonate δ18O are very negative. This is explained by intensive glacial meltwater runoff from surrounding mountain tops and slopes. Negative δ13C values of carbonates reflect the presence of C3 plants near the glacial edge, such as Kobresia sedges. From 10,000 to c. 6500 years ago, the increase of the Artemisia steppe occurring at the same time as an increasingly positive trend in fine-grained carbonate δ18O values are apparently contradictory. This is interpreted by a Westerly trend (increasing humidity) at the altitude of the lake (1607 m) and a monsoonal trend (increasingly dry) at the elevation of the glaciated mountain tops (a reconciliation hypothesis developed for multiple sites, illustrated here within one site only). Whereas the steppe is widespread around the lake, the fine-grain carbonates are precipitated from surface waters strongly influenced by meltwater having spilled down the surrounding mountains that are >2 km higher. Additionally after low lake levels until 10,000 years ago, our data suggest a lake level rise between 10,000 and 8000 years ago. • At 12.7–10 ka, desert to semi-desert and strong meltwater inflow. • At 10–6.5 ka, steppe reflecting increasingly humid climate. • At the same time, surface water δ18O showing drying trend. • One lake recording both low and high elevation climates, Westerlies and monsoonal. • Lake level increasing between 10 and 8 ka. [ABSTRACT FROM AUTHOR]

Abstract: This study presents combined mineralogical, chemical, isotopic (87Sr/86Sr and U–Th disequilibria series) and palynological analyses on bulk sediments and on distinct mineral phases (carbonates and clays) from a 10-m-long core drilled in the southern Caspian Sea and containing a Late Pleistocene and Early Holocene record. The data allowed identifying 1) the main variations in sedimentation, 2) the processes causing these variations, 3) the modification of erosion vs weathering, and 4) the influence of climatic and/or Caspian Sea level changes in the region since the Late Pleistocene. The chemical and mineralogical results allowed the division of the sedimentary sequence into three main units and a transition zone. The lower unit (unit U1) primarily consists of silicate and carbonate-rich detritus. Sedimentation characteristics, including observation of detritus in secular equilibrium, are relatively constant within this unit and reflect mechanical erosion in a cold climate. Unit U1 probably corresponds to a glacial period when the vegetation cover was sparse and wind and river transport of pollen were strong. Subsequently, global increase in temperatures has greatly modified the sedimentation in the Caspian Sea south basin. Biogenic sedimentation is higher in units U2 and U3, and detrital inputs varied from unit U1. Variations in detrital input are likely to be caused by decreasing aeolian contribution and by relative changes in river volumes and origins. The study of the bulk sediments, clays and carbonates reflects an increase in chemical weathering since about 10 14C ka BP ago (base of unit U2), in line with an increase in the vegetation cover. Our results suggest an evolution of continental weathering conditions in the catchment area of the Caspian Sea, from dominantly mechanical/physical erosion during the cold period to a continuous increase in weathering since the Lateglacial period, as climate improved, which illustrates the strong relation between climate, vegetation cover and weathering processes. This paper also highlights how the U–Th disequilibrium series proxy, combined with other geochemical and palynological studies, could be a useful tool to record and constrain the modification of weathering regime in response to climatic and environmental changes at regional scale. [Copyright &y& Elsevier]

Abstract: This study represents the vegetation history of the last 3500 years and conducts an analysis of the climatic fluctuations on a 75km long transect on the western Dead Sea shore. Palynological and sedimentological data are available from six cores near Mount Sedom, Ein Boqueq, and Ein Gedi and from outcrops near Ze''elim and Ein Feshkha. The comparison of the pollen data with the lake levels shows synchronous trends. During the Middle Bronze Age, Iron Age and Hellenistic to Byzantine Period the high lake level of the Dead Sea signals an increase in precipitation. Contemporaneously, values of cultivated plants indicate an increase in agriculture. Lake level is low during the Late Bronze Age, within the Iron Age and at the end of the Byzantine period, indicating dry periods when all pds show a decrease of cultivated plants. Forest regeneration led by drought-resistant pines is observed in all pollen diagrams (pds) following the agricultural decline in the Byzantine period and, in the pds near Ein Boqeq, Ze''elim and Ein Feshkha, during the late Iron Age. The modern vegetation gradient is reflected in the palaeo-records: a stronger expansion of Mediterranean vegetation and cultivated plants in the northern sites is recognisable. [Copyright &y& Elsevier]

Abstract We present results of mineralogical (light, heavy and clay minerals), geochemical and palynological investigations of floodplain sediments at Saqqara. Our investigations provide new insights into our understanding of the source of the Holocene Nile sediments, local palaeoclimate and palaeoenvironment of the floodplain at Saqqara as well as the Holocene palaeoclimatic variations at the Nile headwaters. We also investigate the relationship between Nile floods and global climate changes and the impact of changing flood conditions on episodes of societal and central governmental collapse at the end of the Egyptian Old Kingdom. The Holocene sequences recorded in two shallow drill cores (SAQA 21 and 22) were investigated and subdivided into six sedimentary units, from underlying Late Pleistocene sand and gravels (unit I) to overlying modern soil (unit VIII). Early Holocene sediments were essentially missing in the studied cores, probably due to intensive erosion during the well-known 8.2 kyr cal BP arid event. Middle Holocene sediments are represented by unit II, which reflect high Nile floods of Equatorial African origin with less contribution from Ethiopian sources. The Old Kingdom sediments (unit III), seems to be mainly of White Nile sources with frequent contributions from the Blue Nile. Late Holocene sediments (unit IV-VII) show an increased contribution from Blue Nile River sources. Low Nile flow episodes were recorded at 5.2 (between units II and III), 4.2 (between units III and IV), 3.5 (within unit IV) and 2.7 kyr cal BP (between units V and VI). The second event corresponds to the First Intermediate Period (FIP) and the third probably coincides with the Second Intermediate Period (2nd IP), periods of disorder in Egypt. [ABSTRACT FROM AUTHOR]

Abstract: This magnetic, clay minerals and palynological study provides a record of two Late Pleistocene transgressions (Late Khazarian and Early Khvalynian) in the Caspian Sea, through the analysis of present-day lower Volga terraces. The results allow the clarification of some points about the Caspian Sea evolution during the considered periods. Early diagenetic iron sulphides (greigite and pyrite) are present in sediments of the lower part of the Late Khazarian and reflect restricted water circulation in the basin. The change in iron sulphide mineralogy is most probably related to the change of the water level and its salinity. Low magnetic mineral contents with magnetite, if any, recorded in the upper part of the Late Khazarian, Atelian and Early Khvalynian, reflect a well-oxygenated basin and detrital material sources poor in magnetic minerals. Smectite is the dominant clay mineral in the Late Khazarian, reflecting chemical weathering in its source area due to the wet and warm climate. The upper part of this transgression is nevertheless marked by a stepwise relative decrease of smectite and an increase of illite, attributed to a cooling climate. During the Atelian and Early Khvalynian periods, phases of sandy deposits are characterised by equal proportions of illite and smectite, similar to Ukrainian loess. “Chocolate” clays are clearly dominated by illite. Both clay mineralogies are attributed to cool climate, which favours physical weathering in the catchment area. The conditions of “chocolate” clays deposition are unclear. The recorded cooling during the last phase of the Late Khazarian and the 14C age on a well-preserved bivalve shell, suggest that it is probably much younger than the Eemian interglacial, and could correspond to the Girkan transgression. The 14C age for the Early Khvalynian sample suggests approximately a Last Glacial Maximum age for this transgression. [Copyright &y& Elsevier]