Air temperature and water level inferences from northeastern Lapland (69°N) since the Little Ice Age

• Published in: Polish Polar Research
• Main Authors: Luoto, Tomi P., Kivilä, E. Henriikka, Nevalainen, Liisa, Kotrys, Bartosz, Płóciennik, Mateusz, Rantala, Marttiina V.
• Other Authors: Faculty of Biological and Environmental Sciences, Ecosystems and Environment Research Programme, University of Helsinki, Niemenkatu 73, 15140 Lahti, Finland, Polish Geological Institute - National Research Institute, Pomeranian Branch in Szczecin, Wieniawskiego 20, 71-130 Szczecin, Poland, Department of Invertebrate Zoology and Hydrobiology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland, Institute of Earth Surface Dynamics, University of Lausanne, Géopolis Building, UNIL Mouline-1015, Switzerland
• Format: Article in Journal/Newspaper
• Language: English
• Published: Polish Academy of Sciences; Committee on Polar Research 2020
• Subjects: Arctic; paleoclimate; temperature; Chironomidae; Cladocera; precipitation; Kevo; Polar Research; Lapland
• Online Access: http://hdl.handle.net/11089/39734; https://doi.org/10.24425/ppr.2020.132568

Independent Arctic records of temperature and precipitation from the same proxy archives are rare. Nevertheless, they are important for providing detailed information on long-term climate changes and temperature-precipitation relationships in the context of large-scale atmospheric dynamics. Here, we used chironomid and cladoceran fossil assemblages to reconstruct summer airtemperature and water-level changes, during the past 400 years, in a small lake located in Finnish Lapland. Temperatures remained persistently cold over the Little Ice Age (LIA), but increased in the 20th century. After a cooler phase in the 1970s, the climate rapidly warmed to the record-high temperatures of the most recent decades. The lake-level reconstruction suggested persistently wet conditions for the LIA, followed by a dry period between ~1910 and 1970 CE, when the lake apparently became almost dry. Since the 1980s, the lake level has returned to a similar position as during the LIA. The temperature development was consistent with earlier records, but a significant local feature was found in the lake-level reconstruction – the LIA appears to have been continuously wet, without the generally depicted dry phase during the 18th and 19th centuries. Therefore, the results suggest local precipitation patterns and enforce the concept of spatially divergent LIA conditions. This work was supported by the Emil Aaltonen Foundation (T.P.L., grants numbers 160156, 170161, 180151), Kone Foundation (T.P.L., grant number 090140) and Academy of Finland (L.N., grant numbers 287547, 308954). Support for mobility by the EU Climate-KIC’s Pioneers into Practice program is also appreciated. Help in the fieldwork was provided by Annukka Galkin and the Kevo Research Station. We are grateful for Dr. János Korponai and an anonymous reviewer for their constructive comments on the manuscript.