Lake Korttajarvi, Finland 2000 Year Varved Sediment Data Tiljander, M.; Saarnisto, M.; Ojala, A.E.K.; Saarinen, T. Tiljander, M. Saarnisto, M. Ojala, A.E.K. Saarinen, T. PAGES 2k Network PAGES Arctic 2k earth science/paleoclimate/paleolimnology (varve thickness,null,null,millimeter,null,paleolimnology,null,null,N,x10-4 mm; varve mineral layer thickness) earth science/paleoclimate/paleolimnology (age,null,null,year Common Era,null,paleolimnology,null,null,N,null) earth science/paleoclimate/paleolimnology (varve thickness,null,null,millimeter,null,paleolimnology,null,null,N,x10-4 mm; varve organic layer thickness) earth science/paleoclimate/paleolimnology (absorbance,null,null,dimensionless,null,paleolimnology,null,x-ray densitometry,N,Measured on a grayscale of 0-255) earth science/paleoclimate/paleolimnology (Lake Korttajärvi>LATITUDE 62.33>LONGITUDE 25.683) High-resolution physical analyses (varve thickness and relative X-ray density) were conducted on a 3000-year varved sediment sequence in Lake Korttajarvi, central Finland. Climate and the local environment strongly influence the properties of the lake sediments, and, through a combination of physical proxies, severe and favourable climate periods and anthropogenic effects on sedimentation with an annual to decadal resolution could be detected. We observed previously identified historical climate periods in the Lake Korttajarvi varve record. The Medieval Climate Anomaly (often termed the Medieval Warm Period) of AD 980-1250, which is characterized by highly organic sediment and a minor minerogenic flux during mild winters, started and terminated abruptly, but also included a short (30-year) colder period lasting between AD 1115 and AD 1145. The Little Ice Age, however, was not clear in our record, although there were two minor cooling periods in AD 1580-1630 and AD 1650-1710. Natural variability in the sediment record was disrupted by increased human impact in the catchment area at AD 1720. There is a distinct positive anomaly in mineral matter accumulation between 907 and 875 BC, which indicates more severe climate conditions. This period exists contemporary with a cold event, recorded worldwide, c. 2800 years ago. STUDY NOTES: Sediment varve thickness and X-Ray density data from Lake Korttajarvi, central Finland. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Tiljander, M. Investigator : Saarnisto, M. Investigator : Ojala, A.E.K. Investigator : Saarinen, T. 2009-09-01 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/8659 https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/europe/finland/korttajarvi2003.txt https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/europe/finland/korttajarvi2003.xls https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/europe/finland/korttajarvi2003.txt https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/europe/finland/korttajarvi2003.xls English https://www.ncdc.noaa.gov/paleo/study/8659 https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/europe/finland/korttajarvi2003.txt https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/europe/finland/korttajarvi2003.xls Tiljander, M., M. Saarnisto, A.E.K. Ojala, and T. Saarinen2003A 3000-year palaeoenvironmental record from annually laminated sediment of Lake Korttajarvi, central FinlandBoreas26566-577 START YEAR: 1950 cal yr BP * END YEAR: -35 cal yr BP 25.683 62.33 25.683 62.33