Spectral Analysis of the Svalbard Temperature Record 1912–2010

Autor: Ole Humlum, Jan-Erik Solheim, Kjell Stordahl
Jazyk: angličtina
Rok vydání: 2011
Předmět:
Zdroj: Advances in Meteorology, Vol 2011 (2011)
Druh dokumentu: article
ISSN: 1687-9309
1687-9317
DOI: 10.1155/2011/175296
Popis: Climate development with possible anthropogenic effects occurs on a background of natural climatic variations, which may be considerable, and especially in the Arctic. Natural climate variations however remain poorly understood, although they remain important for discriminating between natural and anthropogenic influences on current climate change. Using the Svalbard (78°N) surface air temperature record 1912–2010 as an example, we here suggest a road ahead to identify and describe such natural climate variations. By means of Fourier and wavelet analysis the record is decomposed into time-frequency space, to extract information on periodic signals and their amplitude and variation over time. By this we identify several cyclic variations on the time scale investigated. These oscillations are present in the annual record, as well as in seasonal subsets of the record. Using only three oscillations it is possible to hindcast the Svalbard temperature record well. We suggest that such persistent oscillations may be used for forecasting the overall features of future temperature changes for a limited period, about 10–25% of the record length. Our main focus is on identifying the character of recurrent natural temperature variations, but we also comment briefly on possible physical explanations for some of the identified cyclic variations.
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