NOAA/WDS Paleoclimatology - Lake Hirvijaervi Holocene Surface Air Temperature Climate Reconstructions

Effective moisture and temperature dynamics during the late glacial and Holocene were reconstructed from fossil midge (Diptera: Nematocera) assemblages in Lake Hirvijärvi, southern Finland. Quantitative inferences were performed using midge-based transfer functions for water depth and mean July air temperature. The aim was to identify major trends in Holocene climate development. The results were generally consistent with patterns found in previous investigations from nearby regions and indicated some distinct differences in palaeoclimate between southern and northern Finland. The results indicate that the region was characterised by a very cold Late Pleistocene, cool and moist but drying early Holocene, warm and moist mid Holocene and cool and moist late Holocene. A progressive trend of increasing lake levels from the early Holocene towards the present was evident. The results of this study provide implications for regional differences in effective moisture between southern and northern Finland during the Holocene. Copyright © 2010 John Wiley & Sons, Ltd.