Search results for "global"

Rhinocerotid tooth enamel 18O/16O variability between 23 and 12 Ma in southwestern France.

2006

Abstract The relationship between the oxygen isotope ratio of mammal tooth enamel and that of drinking water was used to reconstruct changes in the Miocene oxygen isotope ratio of rainfall (meteoric water δ 18 O MW ). These, in turn, are related to climatic parameters (temperature, precipitation and evaporation rate). δ 18 O values of rhinocerotid teeth from the Aquitaine Basin (southwestern France) suggest a significant climatic change between 17 and 12 Ma, characterized by cooling together with precipitation increase, in agreement with other terrestrial and oceanic records. To cite this article: I. Bentaleb et al., C. R. Geoscience 338 (2006).

Five centuries of Central European temperature extremes reconstructed from tree-ring density and documentary evidence

2010

Future climate change will likely influence the frequency and intensity of weather extremes. As such events are by definition rare, long records are required to understand their characteristics, drivers, and consequences on ecology and society. Herein we provide a unique perspective on regional-scale temperature extremes over the past millennium, using three tree-ring maximum latewood density (MXD) chronologies from higher elevations in the European Alps. We verify the tree-ring-based extremes using documentary evidences from Switzerland, the Czech Republic, and Central Europe that allowed the identification of 44 summer extremes over the 1550-2003 period. These events include cold temperat…

Experimental socioecology: Integrative science for anthropocene landscape dynamics

2016

Abstract The emergence of coupled natural and human landscapes marked a transformative interval in the human past that set our species on the road to the urbanized, industrial world in which we live. This emergence enabled technologies and social institutions responsible for human-natural couplings in domains beyond rural, agricultural settings. The Mediterranean Landscape Dynamics Project (MedLand) is studying the interacting social and biophysical processes associated with these novel socioecological systems and their long-term consequences using a new form of 'experimental socioecology' made possible by recent advances in computation. We briefly describe the MedLand modeling laboratory, …

The ELSA-Flood-Stack: A reconstruction from the laminated sediments of Eifel maar structures during the last 60 000 years

2016

Abstract This study reconstructs the main flood phases in central Europe from event layers in sediment cores from Holocene Eifel maar lakes and Pleistocene dry maar structures. These reconstructions are combined with recent gauge time-series to cover the entire precipitation extremes of the last 60 000 years. In general, Eifel maar sediments are perfectly suited for the preservation of event layers since the deep water in the maar lakes is seasonal anoxic and therefore, bioturbation is low. However, the preservation of annual lamination is only preserved in Holzmaar and Ulmener Maar; the other cores are dated by 14C, magnetostratigraphy, tephra markers and ice core tuning. The cores were dr…

The ELSA - Stacks (Eifel-Laminated-Sediment-Archive): An introduction

2016

Climate indices in historical climate reconstructions: a global state of the art

2021

Narrative evidence contained within historical documents and inscriptions provides an important record of climate variability for periods prior to the onset of systematic meteorological data collection. A common approach used by historical climatologists to convert such qualitative information into continuous quantitative proxy data is through the generation of ordinal-scale climate indices. There is, however, considerable variability in the types of phenomena reconstructed using an index approach and the practice of index development in different parts of the world. This review, written by members of the PAGES (Past Global Changes) CRIAS working group – a collective of climate historians a…

2019

Abstract. Records of grape harvest dates (GHDs) are the oldest and the longest continuous phenological data in Europe. However, many available series, including the well-known (Dijon) Burgundy series, are error prone because scholars so far have uncritically drawn the data from 19th century publications instead of going back to the archives. The GHDs from the famous vine region of Beaune (Burgundy) were entirely drawn from the archives and critically cross-checked with narrative evidence. In order to reconstruct temperature, the series was calibrated against the long Paris temperature series comprising the 360 years from 1659 to 2018. The 664-year-long Beaune series from 1354 to 2018 is als…

Timber Logging in Central Siberia is the Main Source for Recent Arctic Driftwood

2015

Abstract Recent findings indicated spruce from North America and larch from eastern Siberia to be the dominating tree species of Arctic driftwood throughout the Holocene. However, changes in source region forest and river characteristics, as well as ocean current dynamics and sea ice extent likely influence its spatiotemporal composition. Here, we present 2556 driftwood samples from Greenland, Iceland, Svalbard, and the Faroe Islands. A total of 498 out of 969 Pinus sylvestris ring width series were cross-dated at the catchment level against a network of Eurasian boreal reference chronologies. The central Siberian Yenisei and Angara Rivers account for 91% of all dated pines, with their oute…

The ELSA tephra stack: Volcanic activity in the Eifel during the last 500,000 years

2016

Abstract Tephra layers of individual volcanic eruptions are traced in several cores from Eifel maar lakes, drilled between 1998 and 2014 by the Eifel Laminated Sediment Archive (ELSA). All sediment cores are dated by 14C and tuned to the Greenland interstadial succession. Tephra layers were characterized by the petrographic composition of basement rock fragments, glass shards and characteristic volcanic minerals. 10 marker tephra, including the well-established Laacher See Tephra and Dumpelmaar Tephra can be identified in the cores spanning the last glacial cycle. Older cores down to the beginning of the Elsterian, show numerous tephra sourced from Strombolian and phreatomagmatic eruptions,…

Coarsely crystalline cryogenic cave carbonate – a new archive to estimate the Last Glacial minimum permafrost depth in Central Europe

2012

Abstract. Cryogenic cave carbonate (CCC) represents a specific type of speleothem whose precipitation is triggered by freezing of mineralized karst water. Coarsely crystalline CCC, which formed during slow freezing of water in cave pools, has been reported from 20 Central European caves located in Germany, the Czech Republic, Slovakia and Poland. All these caves are situated in an area which was glacier-free during the Weichselian. Whereas the formation of usual types of speleothems in caves of this region usually ceased during the glacials, coarsely crystalline CCC precipitation was restricted to glacial periods. Since this carbonate type represents a novel, useful paleoclimate proxy, data…