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• The loess-paleosol section (MIS 5e to MIS 3) on the Russian Upland was studied. • OSL and 14C-dates were obtained for paleosols, sediments, and cryogenic deformations. • For MIS 5e interglacial the duration of pedogenesis was estimated from 12 to 15 ka. • Stages of periglacial conditions during the early, middle and late Valdai were dated. • The obtained chrono-stratigraphic scheme was correlated with other ones in Europe. New results on stratigraphy and chronology, obtained on the basis of OSL and 14C-dating of paleosols, sediments, and cryogenic deformations in the Aleksandrov quarry situated at the Central Russian Upland, are discussed. Due to the location of the site in a paleodepression, the section presents various stages of soil formation, cryogenesis and sedimentation starting from the Mikulino interglacial to the middle last glacial time. The studied sequence is well preserved and one of the most detailed soil-sedimentary terrestrial archives within Eastern Europe. It reflects climatic variations comprising the timespan from the marine isotopic stage (MIS) 5e to MIS 3. At the base of the paleodepression the pedogenetic stages are extraordinary detailed. Distinct paleosols are alternating with erosion-accumulative stages, forming the Ryshkovo pedolitocomplex during the Mikulino interglacial. During the Early Valdai time two interstadial paleosols were developed, and the Middle Valdai section comprises two main interstadial paleosols as well. In general, interstadial paleosols of the Late Valdai time are absent in the studied quarry. For the first time, the chronological boundaries of the MIS 5e interglacial are recorded and thus, the duration of soil formation could be determined from 12 to 15 thousand years. Furthermore, stages of periglacial conditions during the Early, Middle and Late Valdai time were dated. The obtained ages form the base for a chronostratigraphic framework, which was correlated with those of the loess-paleosol archives of Eastern, Central, and Western Europe. [ABSTRACT FROM AUTHOR]

Local to regional paleoenvironmental reactions to past climate changes are preserved in loess-paleosol sequences (LPS). In order to extract this information we used a multi-methodological approach in the Upper Paleolithic site of Krems-Wachtberg East in Lower Austria. Detailed field studies and high-resolution geochemical, colorimetric, and granulometric analyses help to understand the interplay between soil formation, loess accumulation, and surface processes. In comparison to the main profile/excavation of Krems-Wachtberg 2005–2015 it can be stated that OSL- and 14 C-ages as well as the (archeological) stratigraphy of both profiles are comparable. However, pedogenic features are more evident at Krems-Wachtberg East. The new investigations show that well-established weathering indices do not clearly trace interstadial soil formation in the studied profile. Apart from this fact, single specific elements like Fe and Mg react more sensitive to initial pedogenic processes. Weak pedogenesis can further be evidenced by quantitative spectrophotometric results. The latter is also capable of refining and supporting the stratigraphy/pedology based on field analyses. As a general rule, next to loess also initial soil horizons of the MIS 3 are remarkably rich in primary carbonates indicating that soil formation took place in an alkaline environment. Due to the fact that hydrolysis of feldspars could not clearly be detected by the application of pedochemical indices, soil formation was probably limited to the oxidation of iron bearing minerals and weak carbonate leaching. These phases of favorable climatic conditions in terms of pedogenesis were terminated by increasing dust input towards the onset of MIS 2. The eolian deposits are overprinted during reducing conditions in soils and/or modified by colluvial processes. Altogether, weak pedogenesis can be reliably detected using a multi-methodological approach which leads to enhanced paleoenvironmental interpretations. The OSL-ages put the profile in a range of ∼41 to 30 ka. We present a tentative correlation of the studied loess profile to the record of the North Greenland Ice Core Project (NGRIP) for the part of the profile where OSL and 14 C complement each other. [ABSTRACT FROM AUTHOR]

The European Alps and their forelands provide a range of different archives and climate proxies for developing climate records in the time interval 60–8 thousand years (ka) ago. We review quantitative and semi-quantitative approaches for reconstructing climatic variables in the Austrian and Swiss sector of the Alpine region within this time interval. Available quantitative to semi-quantitative climate records in this region are mainly based on fossil assemblages of biota such as chironomids, cladocerans, coleopterans, diatoms and pollen preserved in lake sediments and peat, the analysis of oxygen isotopes in speleothems and lake sediment records, the reconstruction of past variations in treeline altitude, the reconstruction of past equilibrium line altitude and extent of glaciers based on geomorphological evidence, and the interpretation of past soil formation processes, dust deposition and permafrost as apparent in loess-palaeosol sequences. Palaeoclimate reconstructions in the Alpine region are affected by dating uncertainties increasing with age, the fragmentary nature of most of the available records, which typically only incorporate a fraction of the time interval of interest, and the limited replication of records within and between regions. Furthermore, there have been few attempts to cross-validate different approaches across this time interval to confirm reconstructed patterns of climatic change by several independent lines of evidence. Based on our review we identify a number of developments that would provide major advances for palaeoclimate reconstruction for the period 60–8 ka in the Alps and their forelands. These include (1) the compilation of individual, fragmentary records to longer and continuous reconstructions, (2) replication of climate records and the development of regional reconstructions for different parts of the Alps, (3) the cross-validation of different proxy-types and approaches, and (4) the reconstruction of past variations in climate gradients across the Alps and their forelands. Furthermore, the development of downscaled climate model runs for the Alpine region 60–8 ka, and of forward modelling approaches for climate proxies would expand the opportunities for quantitative assessments of climatic conditions in Europe within this time-interval. [ABSTRACT FROM AUTHOR]

The complex interplay of dust sedimentation, pedogenesis, and erosion/reworking in the formation of loess-paleosol sequences (LPS) challenges paleoenvironmental proxies. Here we show that color and grain size are essential parameters characterizing loess profiles and support robust stratigraphies as a basis for reconstructions in the context of local geo-ecological and large-scale paleoclimatic evolution. Detailed paleoenvironmental records from the period since the arrival of anatomically modern humans to the last glacial maximum are scarce in the Alpine surroundings. The c. 7.5 m thick LPS Krems-Wachtberg, NE Austria, known for its well-preserved Upper Paleolithic context at a depth of 5.5 m, formed between 40 and 20 ka BP by quasi-continuous dust-sedimentation, interrupted by phases of incipient pedogenesis and local reworking. The new KW2015 composite is based on three sections studied and sampled at 2.5 cm resolution. Color and grain size data support a robust stratigraphy for reconstructions of the pedosedimentary evolution. The marked transition from oxidized to reduced paleosols of KW2015 around 34–35 ka corresponds to the Middle-to Upper Pleniglacial transition as part of a general cooling trend from marine isotope stage (MIS) 3 to 2, intensely modulated by millennial-scale climatic fluctuations as recorded in the Greenland ice core data. The distinct response of KW2015 to these trends highlights that reconstructing LPS evolution based on a robust stratigraphy is a prerequisite to paleoenvironmental proxy interpretation. • 7.2 m thick loess studied at the Upper Paleolithic Krems-Wachtberg site (KW2015). • Detailed KW2015 stratigraphy supported by high-resolution color and grain size data. • Complex pedosedimentary evolution challenges standard paleoenvironmental proxies. • Detailed Middle- to Upper Pleniglacial paleoenvironmental record in the NE Alpine forelands. • Distinct local response of KW2015 to large-scale paleoclimatic shifts (MIS 3/2 transition). [ABSTRACT FROM AUTHOR]