Abstract
Quantitative estimates of 1480 years of summer temperatures in northern Fennoscandia have previously been derived from continuous treering records from northern Sweden. Here we show the results of spectral analyses of these data. Only a few peaks in the spectra are consistently significant when the data are analyzed over a number of sub-periods. Relatively timestable peaks are apparent at periods of 2.1, 2.5, 3.1, 3.6, 4.8, ∼ 32–33 and for a range between ∼ 55–100 years. These results offer no strong evidence for solar-related forcing of summer temperatures in these regions. Our previously published reconstruction was limited in its ability to represent long-timescale temperature change because of the method used to standardize the original tree-ring data. Here we employ an alternative standardization technique which enables us to capture temperature change on longer timescales. Considerable variance is now reconstructed on timescales of several centuries. In comparison with modern normals (1951–70) generally extended periods when cool conditions prevailed, prior to the start of the instrumental record, include 500–700, 790–870, 1110–1150, 1190–1360, 1570–1750 (A.D.) with the most significant cold troughs centred on about 660, 800, 1140, 1580–1620 and 1640. Predominantly warm conditions occurred in 720–790, 870–1110 and 1360–1570 with peaks of warmth around 750, 930, 990, 1060, 1090, 1160, 1410, 1430, 1760 and 1820.
Similar content being viewed by others
References
Aniol RW, Eckstein D (1984) Dendroclimatological studies at the northern timberline. In: Morner N-A, Karlen W (eds) Climate changes on a yearly to millennial basis. Reidel, Dordrecht, pp 273–279
Bartholin TS (1984) Dendrochronology in Sweden. In: Morner NA, Karlen W (eds) Climate changes on a yearly to millenial basis. Reidel, Dordrecht, pp 261–262
Bartholin TS, Karlen W (1983) Dendrokronologie: Lapland. Dendrokronol Sällsk Medd 5:3–16
Becker M (1989) The role of climate on present and past vitality of silver fir forests in the Vosges mountains of northeastern France. Can J Forest Res 19:1110–1117
Briffa KR, Jones PD (1990) Basic chronology statistics and assessment. In: Cook ER, Kairiukstis LA (eds) Methods of dendrochronology: applications in the environmental sciences. Kluwer/IIASA, Dordrecht, pp 137–152
Briffa KR, Schweingruber FH (1992) Recent dendroclimatic evidence of northern and central European summer temperatures. In: Bradley RS, Jones PD (eds) Climate since A.D. 1500. Routledge, London, pp 366–392
Briffa KR, Bartholin TS, Eckstein D, Jones PD, Karlen W, Schweingruber FH, Zetterberg P (1990) A 1400-year tree-ring record of summer temperatures in Fennoscandia. Nature 346:434–439
Cook ER, Briffa KR (1990) A comparison of some tree-ring standardization methods. In: Cook ER, Kairiukstis LA (eds) Methods of dendrochronology: applications in the environmental sciences. Kluwer/IIASA, Dordrecht, pp 153–162
Cook ER, Briffa KR, Shiyatov S, Mazepa V (1990) Tree-ring standardization and growth-trend estimation. In: Cook ER, Kairiukstis LA (eds) Methods of dendrochronology: applications in the environmental sciences. Kluwer/IIASA, Dordrecht, pp 104–123
Fritts HC (1976) Tree rings and climate. Academic Press, London, UK
Fritts HC, Swetnam TW (1986) Dendroecology: a tool for evaluating variations in post and present forest environments. Laboratory of Tree-Ring Research, University of Arizona, Tucson, USA
Grove JM (1988) The Little Ice Age. Methuen, London, UK
Jones PD, Bradley RS (1992) Climate variations in the longest instrumental records. In: Bradley RS, Jones PD (eds) Climate since A.D. 1500. Routledge, London, pp 246–268
Jones PD, Kelly PM (1983) The spatial and temporal characteristics of northern hemisphere surface air temperature variations. J Climatol 3:243–252
Kelly PM, Jones PD, Sear CB, Cherry BSG, Tavakol RK (1982) Variations in surface air temperatures: Part 2 Arctic Regions, 1881–1980. Mon Wea Rev 110:71–83
Lamb HH (1963) What can we find out about the trend of our climate? Weather 18:194–216
Lamb HH (1965) The early medieval warm epoch and its sequel. Palaeogeogr, Palaeoclimatol, Palaeoecol 1:13–37
Lamb HH (1977) Climate: present, past and future, Vol 2, Climate history and the future. Methuen, London, UK
Mitchell VL (1967) An investigation of certain aspects of tree growth rates in relation to climate in the central Canadian boreal forest. University of Wisconsin, Dept. Meteorology Technical Report 33, Task NR 387-022, ONR Contract 1202(07), NSF GP-5572X, Madison, USA
Renberg I, Segerström U, Wallin J-E (1984) Climatic reflection in varved lake sediments. In: Morner N-A, Karlen W (eds) Climatic changes on a yearly to millennial basis. Reidel, Dordrecht, pp 249–256
Schweingruber FH, Bartholin TS, Schar E, Briffa KR (1988) Radiodensitometric-dendroclimatological conifer chronologies from Lapland (Scandinavia) and the Alps (Switzerland). Boreas 17:559–566
Siren G, Hari P (1971) Coinciding periodicity in recent tree rings and glacial clay sediments. Report of the Kevo Subarctic Research Station 8:155–157
Stephenson FR, Wolfendale AW (eds) (1988) Secular solar and geomagnetic variations in the last 10000 years. Kluwer, Dordrecht, Netherlands
Wigley TML, Briffa KR, Jones PD (1984) On the average value of correlated time series, with applications in dendroclimatology and hydrometeorology. J Clim Appl Meteorol 23:201–213
Williams LD, Wigley TML (1983) A comparision of evidence for late Holocene summer temperature variations in the Northern Hemisphere. Quatern Res 20:286–307
Author information
Authors and Affiliations
Additional information
Offprint requests to: KR Briffa
Rights and permissions
About this article
Cite this article
Briffa, K.R., Jones, P.D., Bartholin, T.S. et al. Fennoscandian summers from ad 500: temperature changes on short and long timescales. Climate Dynamics 7, 111–119 (1992). https://doi.org/10.1007/BF00211153
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00211153