These modeling results have enormous implications for paleoreconstructions of the MIS31 climate that assume overall ice-free conditions in the vicinity of the Antarctic continent. Since these reconstructions may depict dominant signals in a particular time interval and locale, they cannot be assumed to geographically represent large-scale domains, and their ability to reproduce long-term environmental conditions should be considered with care.

Global sea level rise during the last deglacial flooded the Siberian continental shelf in the Arctic Ocean. Sediment cores, radiocarbon dating, and microfossils show that the regional sea level in the Arctic rose rapidly from about 12 500 to 10 700 years ago. Regional sea level history on the Siberian shelf differs from the global deglacial sea level rise perhaps due to regional vertical adjustment resulting from the growth and decay of ice sheets.

Based on mineral records from the northern Chukchi Sea, we report a long-term decline in the Beaufort Gyre (BG) strength during the Holocene, consistent with a decrease in summer insolation. Multi-centennial variability in BG circulation is consistent with fluctuations in solar irradiance. The Bering Strait inflow shows intensification during the middle Holocene, associated with sea-ice retreat and an increase in marine production in the Chukchi Sea, which is attributed to a weaker Aleutian Low.

We assembled a very accurate geological timescale from the interval 47.8 to 56.0 million years ago, also known as the Ypresian stage. We used cyclic variations in the data caused by periodic changes in Earthäs orbit around the sun as a metronome for timescale construction. Our new data compilation provides the first geological evidence for chaos in the long-term behavior of planetary orbits in the solar system, as postulated almost 30 years ago, and a possible link to plate tectonics events.

We present a high-resolution multi-proxy study of the Norwegian Sea, covering the 5.33 to 3.14 Ma time window within the Pliocene. We show that large-scale climate transitions took place during this warmer than modern time, most likely in response to ocean gateway transformations. Strong warming at 4.0 Ma in the Norwegian Sea, when regions closer to Greenland cooled, indicate that increased northward ocean heat transport may be compatible with expanding glaciation and Arctic sea ice growth.

We introduce a Bayesian framework to represent layer-counted proxy records as probability distributions on error-free time axes, accounting for both proxy and dating errors. Our method is applied to NGRIP δ¹⁸O data, revealing that the cumulative dating errors lead to substantial uncertainties for the older parts of the record. Applying our method to the widely used radiocarbon comparison curve derived from varved sediments of Lake Suigetsu provides the complete uncertainties of this curve.

We show that the analysis of δ¹⁸O and dust in the Greenland ice cores, and a critical study of their source variations, reconciles these records with those observed on the Eurasian continent. We demonstrate the link between European and Chinese loess sequences, dust records in Greenland, and variations in the North Atlantic sea ice extent. The sources of the emitted and transported dust material are variable and relate to different environments.

We used a new classification of daily weather patterns to analyse the influence of solar variability (11-year cycle) on European climate from 1763 to 2009. The analysis of the weather patterns occurrences shows a reduction in the number of days with a westerly flow over Europe under low solar activity during late winter. In parallel, the number of days with an easterly flow increases. Based on these results we expect colder winter over Europe under low solar activity.

In this study we investigate land-to-ocean transfer and the fate of permafrost carbon in the East Siberian Sea from the early Holocene until the present day. Our results suggest that there was a high input of terrestrial organic carbon to the East Siberian Sea during the last glacial–interglacial period caused by permafrost destabilisation. This material was mainly characterised as relict Pleistocene permafrost deposited via coastal erosion as a result of the sea level rise.

The early Holocene climate is characterized as an interglacial boundary condition without substantial human influence. Here we present a high-resolution CH₄ record covering the early Holocene. The results show that abrupt cooling in Greenland and southward migration of ITCZ were able to induce an ~20 ppb CH₄ decrease on a millennial timescale. The inter-polar difference exhibits a gradual increase during the early Holocene, implying the strengthening of northern extratropical emission.

We show the results of transient simulations with a coupled climate–ice sheet model over the past 38 million years. The CO₂ forcing of the model is inversely obtained from a benthic δ¹⁸O stack. These simulations enable us to study the influence of ice sheet variability on climate change on long timescales. We find that ice sheet–climate interaction strongly enhances Earth system sensitivity and polar amplification.

Ice ages are paced by astronomical parameters. On longer timescales, the astronomy also acts on climate, as evidenced by the 400 kyr signature observed in carbon isotopic records. In this paper, I present a conceptual model that links the astronomy to the dynamics of organic carbon in coastal areas. The model reproduces the carbon isotopic records and a two-step decrease in atmospheric CO₂ that would explain the Pleistocene (~ 2.8 Myr BP) and mid-Pleistocene (~ 0.8 Myr BP) transition.

Past glacial activity on the East Siberian continental margin is poorly known, partly due to the lack of geomorphological evidence. Here we present geophysical mapping and sediment coring data from the East Siberian shelf and slope revealing the presence of a glacially excavated cross-shelf trough reaching to the continental shelf edge north of the De Long Islands. The data provide direct evidence for extensive glacial activity on the Siberian shelf that predates the Last Glacial Maximum.

Pollen-based past climate reconstruction for regions with long-term human occupation is always controversial. We examined the bias induced by the human impact on vegetation in a climate reconstruction for temperate eastern China by comparing the deviations in the reconstructed results for a fossil record based on two pollen–climate calibration sets. Climatic signals in pollen assemblages are indeed obscured by human impact; however, the extent of the bias could be assessed.