CR 58:15-28 (2013)  -  DOI: https://doi.org/10.3354/cr01184

ABSTRACT: Lake levels can act as valuable proxy sources for long-term effective precipitation dynamics. In this study, lake-level fluctuations were reconstructed from the Little Ice Age (LIA) until the present using a multiproxy paleolimnological approach from Lake Moaralm (Moaralmsee) in the Niedere Tauern Alps, Austria. Quantitative lake level reconstruction techniques were applied to the sediment core data using intralake (Moaralmsee) calibration models based on fossil Chironomidae and Cladocera assemblages, and supplementary models based on oribatid mites and loss-on-ignition were used. The results showed that the inferred lake-level trends were strongly correlated among one another and also with the observed precipitation record from an adjacent weather station since 1860 AD. Periods of low lake level were reconstructed for ca. 1600-1650 AD and 1700-1900 AD, while high lake level periods occurred from ca. 1650-1700 AD and from ca. 1900 AD to the present. These results were in good agreement with previous records on lake level and precipitation patterns in the European Alps, though with some spatiotemporal differences. Our records of long-term patterns of effective moisture, combined with the previously established temperature variability since the 17th century, suggested that a period of high effective moisture occurred between ca. 1650 and 1700 AD during the LIA, after which moisture levels decreased. High temperatures during the last century were accompanied by increasing moisture, and the lake levels are now at a 400-yr maximum. This study provides a new proxy for spatiotemporal moisture patterns that is invaluable for improved understanding of synoptic climate variability for periods prior to the observational records.

KEY WORDS: Chironomidae · Cladocera · Lake sediments · Loss-on-ignition · Oribatida · Paleoclimate · Precipitation