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Correlations and periodicities in Himalayan tree ring widths and temperature anomalies through wavelets

Prasanta K. Panigrahi·P. Manimaran·Ananth Lakhmi·Ram R. Yadav
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Abstract

We have studied periodicities and correlation properties of tree ring width chronology of deodar tree from Joshimath (1584 - 1999 years) and Uttarkashi (1500 - 2002 years) in the western Himalayas and the pre-monsoon (March-April-May) temperature anomalies (1876 - 2003) relative to 1961 -1990 mean, through wavelet analysis. Periodic behavior is observed in the tree ring chronology with periodicity in the form 11, 22, and 42 years. The analysis of the self-similar nature reveals long-range correlation with a Hurst exponent, $H >0.5$. These are anti-correlated with the temperature anomalies. An interesting inversion behavior is observed around the year 1750. The power spectral analysis of the time series corroborate the results of wavelet method.

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Prasanta K. Panigrahi, P. Manimaran, Ananth Lakhmi, Ram R. Yadav. 2006-04-01. Correlations and periodicities in Himalayan tree ring widths and temperature anomalies through wavelets. https://arxiv.org/abs/nlin/0604002

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