A Neuro Fuzzy Technique for Modelling Climatic Variations in the Plio-Pleistocene
نویسنده
چکیده
— In this paper a new approach to model climatic variations in the Plio-Pleistocene is presented. In a recent reference, Rial in [1] introduced the working hypothesis that frequency modulation (FM) of the orbital eccentricity forcing may be an important source of the nonlinearities observed in the δO time series from deep-sea sediment cores. Two models are proposed based on the ANFIS (Adaptive Neuro Fuzzy Inference System) structure. The first model uses only past values of the time series under investigation. The second model uses information on the orbital eccentricity forcing and an artificially generated FM which is an extension of the FM signal proposed by Rial. The two models are compared in the light of long term predictions. Key-Words:Astronomical forcing; Climate variations; Embedding dimension; Neuro-fuzzy; Frequency modulation; Nonlinear models.
منابع مشابه
Plio-pleistocene diversification and connectivity between mainland and Tasmanian populations of Australian snakes (Drysdalia, Elapidae, Serpentes).
The genus Drysdalia contains three recognised species of elapid (front-fanged) snakes, distributed across south-eastern Australia (including Tasmania). Here we aim to clarify the biogeography and phylogeographical relationships of this poorly documented region. We conducted molecular phylogenetic and dating analyses, using mitochondrial genes (ND4 and cyt-b). Our analyses suggest that divergenc...
متن کاملClimatic change as an engine for speciation in flightless Orthoptera species inhabiting African mountains.
Many East African mountains are characterized by an exceptionally high biodiversity. Here we assess the hypothesis that climatic fluctuations during the Plio-Pleistocene led to ecological fragmentation with subsequent genetic isolation and speciation in forest habitats in East Africa. Hypotheses on speciation in savannah lineages are also investigated. To do this, mitochondrial DNA sequences fr...
متن کاملEvolutionary Diversification of the Lizard Genus Bassiana (Scincidae) across Southern Australia
BACKGROUND Relatively recent (Plio-Pleistocene) climatic variations had strong impacts on the fauna and flora of temperate-zone North America and Europe; genetic analyses suggest that many lineages were restricted to unglaciated refuges during this time, and have expanded their ranges since then. Temperate-zone Australia experienced less severe glaciation, suggesting that patterns of genetic st...
متن کاملMacrofossils as Indicators of Plio-pleistocene Climates in Tasmania and Antarctica
HILL, R.S. & ]ORDAN, G.]., 1996 (xi): Macrofossils as indicators of Plio-Pleistocene climates in Tasmania and Antarctica. In Banks, M.R. & Brown, M.]. (Eds): CLIMATIC SUCCESSION AND GLACIAL HISTORY OF THE SOUTHERN HEMISPHERE OVER THE LAST FIVE MILLION YEARS. Pap. Proc. R. Soc. Tasm. 130(2): 9-15. ISSN 0080-4703. Department of Plant Science, University of Tasmania, GPO Box 252-80, Hobart, Tasman...
متن کاملReassessment of the Position of the Plio-pleistocene Boundary: Is There a Case for Lowering It to the Gaussimatuyama Palaeomagnetic Reversal?
Forty eight years have elapsed since formal discussions were initiated, in 1948, on the position of the PlioPleistocene boundary. At the 18th International Geological Congress held in London during that year the Commission on the Plio-Pleistocene boundary recommended that “the Lower Pleistocene should include as its basal member the marine Calabrian Formation together with its terrestrial (cont...
متن کامل