Arne Ramisch

Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ | GFZ · Division of Climate Dynamics and Landscape Evolution

The necropolis of Dahshur in northern Egypt witnessed human–environment interaction on a millennial scale but to an unknown extent. The present study aims to decipher ephemeral channel networks, which are common landscape features in the surroundings of the necropolis, from landforms that were subject to human influence. The analysis was carried ou...

Extra-tropical circulation systems impede poleward moisture advection by the Indian Summer Monsoon. In this context, the Himalayan range is believed to insulate the south Asian circulation from extra-tropical influences and to delineate the northern extent of the Indian Summer Monsoon in central Asia. Paleoclimatic evidence, however, suggests incre...

The Southern Kalahari Drainage network is in a key position to analyze spatiotemporal changes in the tropical easterly and the temperate westerly circulation over the Southern African subcontinent. However, due to the prevailing aridity, paleoenvironmental archives within the southwestern Kalahari are sparse and often discontinuous. Hence, little i...

Reading the sediment record in terms of past climates is challenging since linking climate change to the associated responses of sedimentary systems is not always straightforward. Here we analyze the erosional response of landscapes on the Tibetan Plateau to interglacial climate forcing. Using the theory of dynamical systems on Holocene time series...

Varved lake sediments provide climatic records with seasonal to annual resolution and low associated age uncertainty. Robust and detailed comparison of well-dated and annually laminated sediment records is crucial for reconstructing abrupt and regionally time-transgressive changes as well as validation of spatial and temporal trajectories of past c...

The sediment profile from Lake Gościąż in central Poland comprises a continuous, seasonally resolved and exceptionally well-preserved archive of the Younger Dryas (YD) climate variation. This provides a unique opportunity fordetailed investigation of lake system responses during periods of rapid climate cooling (YD onset) and warming (YD terminatio...

The British Isles lack long high-precision and independent chronologies to reconstruct Holocene environmental and climatic conditions at sub-decadal timescales. This paper reports the first Holocene varved chronology for the lacustrine sediment record of Diss Mere in the UK. The record of Diss Mere is 15 m long, and shows 4.2 m of finely-laminated...

The varved sediment of Lake Gościąż (Central Poland) is one of the most detailed and complete climate archives of the Late Glacial and the Holocene in Central Europe. Here, we present microfacies analyses in combination with μXRF core scanning and a detailed varve chronology of a new and continuous GOS18 sediment record. This record presents six li...

Abstract. Varved lake sediments provide long climatic records with high temporal resolution and low associated age uncertainty. Robust and detailed comparison of well-dated and annually laminated sediment records is crucial for reconstructing abrupt and regionally time-transgressive changes as well as validation of spatial and temporal trajectories...

Stable carbon isotopes of sediment organic matter (δ¹³COM) are widely applied in paleoenvironmental studies. Interpretations of δ¹³COM, however, remain challenging and factors that influence δ¹³COM may not apply across all lakes. Common explanations for stratigraphic shifts in δ¹³COM include changes in lake productivity or changes in inputs of allo...

Palaeoclimate reconstruction on the northern Tibetan Plateau resulted in a large spectrum of different and partly divergent interpretations for the climate evolution during the late glacial and the Holocene. In some cases this is caused by incomplete understanding of the geomorphological processes influencing the different proxies used. To overcome...

During expedition 202 aboard the RV Sonne in 2009, 39 seafloor surface sediment sites were sampled over a wide sector of the North Pacific and adjoining Bering Sea. The data served to infer land–ocean linkages of terrigenous sediment supply in terms of major sources and modes of sediment transport within an over-regional context. This is based on a...

Extra-tropical circulation systems impede poleward moisture advection by the Indian Summer Monsoon. In this context, the Himalayan range is believed to insulate the south Asian circulation from extra-tropical influences and to delineate the northern extent of the Indian Summer Monsoon in central Asia. Paleoclimatic evidence, however, suggests incre...

During expedition 202 of research vessel SONNE in 2009, 39 sea-floor surface sediments were sampled over a wide area across the North Pacific and the Bering Sea, which are well suited as reference archives of modern environmental processes. In this study, we used the samples to infer the documentation of land-ocean linkages of terrigenous sediment...

Aquatic macrophytes from a lacustrine environment are highly prone to a reservoir effect, resulting in an overestimation of age. This is often caused by the incorporation of dissolved carbon (CO2 and HCO3−) through photosynthesis from lake waters that have a different 14C activity than the atmosphere. The atmosphere-water disparity is often produce...

In autumn 2009 and spring 2010 the work of the German Archaeological Institute, Cairo and the Free University of Berlin was continued at Dahshur. The lower causeway of the Bent Pyramid had already been discovered by magnetometric measurements and drillings deep below the present surface in 2008. Now a part of the lower causeway was excavated and it...

In spring 2009, the work of the German Archaeological Institute, Cairo and of the Free University of Berlin at Dahshur was continued. The focus was laid on the excavation and documentation of Middle Kingdom shafts. The shafts are organized in one north-southern and one east-western row and are situated in a cemetery to the west of the pyramid of Am...

Siberian larch forests growing on shallow permafrost soils have not, until now, been considered to be controlling the abiotic and biotic characteristics of the vast number of thaw-lake ecosystems. Here we show, using four independent data sets (a modern data set from 201 lakes from the tundra to taiga, and three lake-core records), that lake-water...

The landscape evolution of the area surrounding the necropolis of Dahshur (Egypt) is analysed on the basis of geomorphological investigations and the integration of late Holocene sediment characteristics. Knowledge of the ancient landscape and palaeoenvironmental conditions allows a better understanding of spatial relationships between monuments an...