Orbital forcings of the Earth’s climate in wavelet domain

• Main Authors: Glushkov, A. V., Khokhlov, V. N., Loboda, N. S., Rusov, V. D., Vaschenko, V. N.
• Format: Text
• Language: English
• Published: 2018
• Subjects: geo; envir; Antarctic; The Antarctic; Antarc*; ice core
• Online Access: https://doi.org/10.5194/cpd-1-193-2005; https://cp.copernicus.org/preprints/cpd-2005-0009/

We examine two paleoclimate proxy records – the temperature differences from the Antarctic Vostok ice core and the composite δ18O record from three sites (V19-30, ODP 677, and ODP 846) – in order to search for indications of orbital forcings. We demonstrate that the non-decimated wavelet transform is an appropriate tool for investigating temporarily changing spectral properties of records. Our results indicate that abrupt climate warmings with cyclicity of ~100 kiloyears during the last 400 kiloyears were caused by the combined unidirectional influences of three orbital parameters and the eccentricity can be considered as a modulator defining transitions from the Ice Ages to the periods of comparative warmings. Non-decimated wavelet transform avails discovering the possible part played in climate change by the eccentricity-forced variations. Up to approximately 1.7 million years BP, the influence of this variations of eccentricity appears in increasing for almost all local maxima of δ18O. Since the ~1.7 million years BP, minor and significant maxima alternated and this not affected as much the variations of δ18O.