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Research title Testing European climate synchronicity since the last glacial maximum by constraining the deglaciation histories of Scotland and Romania using surface exposure dating and glacial geomorphology.. Summary of research Detailed knowledge of the climatic and environmental development during the Late Devensian and Holocene stems mainly from investigations in western and northern Europe, with only fragmentary evidence from regions situated in eastern and/or southeastern Europe. To fully address the temporal and spatial variability of Late Glacial and Holocene climate fluctuations, and their impact on the environment, more palaeoenvironmental information is needed from hitherto poorly covered regions.
Recent studies of lake sediments at intermediate elevations (ca. 750m) in northwest Romania have revealed a variable climate ranging from cold and dry during three periods since the Late Glacial separated by warm and moist periods similar to the present climate (Feurdean and Bennike, 2004). The cold and dry periods match reasonably well with the timing of cooling derived from the GRIP ice core in Greenland. However, palaeotemperatures derived from the palaeoecological studies do not agree well with palaeotemperatures derived from atmospheric general circulation models (e.g. Kutzbach, 1998) and do not elucidate temperatures at higher altitudes in the Eastern Carpathians, the most easterly glaciated region of southern Europe. To improve our understanding of climatic and environmental development requires palaeoenvironmental data from different latitudes and altitudes. This project will attempt to test climate synchronicity between the Rodna Mountains, Eastern Carpathians, Romania (high altitude, mid latitude) and NW Scotland (low elevation, high latitude).
The Rodna Mountains were glaciated in the past, however, there are no constraints on the timing of this glaciation. The first aim of this project is to map the glacial limits (moraines, trimlines, glacially modified bedrock forms) in the Rodna Mountains and determine their relative chronology using field techniques and remote sensing. The relative chronology, based on stratigraphic relationships and weathering characteristics of the glacial deposits, will be supplemented with surface exposure dating using the in situ produced cosmogenic nuclides 10Be and 26Al. When the spatial and temporal limits of glaciation have been established it will be possible to reconstruct individual ice masses and determine the palaeoenvironmental conditions within the Rodna Mountains.
The second broad aim of the project is to compare the deglaciation history of the Rodna Mountains with that of NW Scotland, which is currently being investigated by researchers at the University of Glasgow and the British Geological Survey. The comparison between Scotland, which was covered by continental glaciation, and the Rodna Mountains, Romania, which were covered by alpine glaciers, will provide new insights into European climate synchronicity.
The Romanian Carpathians may preserve a unique record of Late Quaternary glaciation and palaeoclimate, reflecting climate changes that might be out of phase with the broader NW European transition. In this project the hypothesis of European climate synchronicity will be tested.
Terrestrial cosmogenic nuclides (TCN)) are formed in minerals near the Earth’s surface by cosmic ray bombardment. Accelerator mass spectrometry allows measurement of these very rare nuclides. Surface exposure dating is used in glacial geomorphology to determine exposure histories of glacially abraded rock surfaces and erratic boulders after they become exposed upon deglaciation. The Department of Geography and Earth Sciences (GES) in collaboration with the Scottish Universities Environmental Research Centre (SUERC) is one of the European leaders in this dating technique.
Even though there is evidence of past glacial activity in Romanian mountains, no glaciers are present today. In general, glacial deposits in this region are well preserved and suitable for cosmogenic dating because of the combination of high altitudes, low to moderate tectonic activity, and dry to moderately wet climate.
The final result of this work will be maps showing the extent and chronology of alpine glaciation in the Rodna Mountains, Romania and GIS digital files containing this information. Supervisors Dr Derek Fabel
Dr Jim Hansom
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