Quantitative calibration of remote mountain lake sediments as climatic recorders of air temperature and ice-cover duration. Arctic, Antarctic and Alpine Research, 37(4): 626-635.

• Main Authors: Thompson, R., Cameron, N., Jones, V., Bigler, C., Rosén, P., Hall, R. I., Catalán, Jordi, García, J., Weckstrom, J., Korhola, A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: University of Colorado 2005
• Subjects: Antarctic; Arctic; Antarc*; Antarctic and Alpine Research; Fennoscandian
• Online Access: http://hdl.handle.net/10261/44436; https://doi.org/10.1657/1523-0430(2005)037[0626:QCORMS]2.0.CO;2

10 páginas. A combination of empirical modeling and a diatom-based transfer function was developed to reconstruct air temperature and ice-cover duration through the study of lake sediments. By using a thermal degree-day modeling approach, ice-cover duration on European mountain and sub-Arctic lakes is found to be very sensitive to temperature change. For example, our model, which incorporates a weather generator, predicts a 100-day shortening in ice-cover duration for a 3°C temperature rise for catchments at elevations of 1500 m in the Southern Alps and the Pyrenees. For the more maritime lakes of Scotland, 30% higher sensitivities (130 d per 3°C) are found, whereas lakes in northwest Finland, in a more continental setting, have only half the sensitivity (50 d per 3°C). A pan-European data set of the species abundance of 252 diatom taxa in 459 mountain and sub-Arctic lakes has been compiled and taxonomically harmonized. Transfer functions were created that relate both seasonal air temperature and ice-cover duration to diatom species composition on the basis of a weighted averaging-partial least squares (WA-PLS) approach. Cross validation was used to test the transfer functions. For ice-cover duration the pan-European data set yields an R-squared value of 0.73, a jack-knifed R-squared value of 0.58, and a residual-mean-square error of prediction (RMSEP) of 23 days. A regional, northern Fennoscandian transect (151 lakes, 122 taxa) yields a jack-knifed R-squared value of 0.50 and an RMSEP of 9 days. For air temperature the pan-European database displayed greatest skill when reconstructing winter or spring temperatures. This result contrasts with the summer temperatures normally studied when using local elevation gradients. The northern Fennoscandian transect has a remarkably low winter RMSEP of 0.73°C. Peer reviewed