Using wavelet decomposition method to retrieve the solar and the global air temperature signals from Greenland, Andes and East Antarctica delta O-18 ice core records

Autor(es)

Evangelista, Heitor ; De Souza Echer, Mariza P. ; Echer, Ezequiel

• Tipo de documento: Artigo Científico
• Fonte: Anais da Academia Brasileira de Ciências; v. 94, p. 15-pg., 2022-01-01.

Resumo

The surface global air temperature (SGAT) and the solar activity presented near similar trends until approximately the 1980's decade, when they start to diverge significantly. This divergence in both time series is attributed to the impact of addition players acting in the climate system as the greenhouse gas emissions and a more active ENSO (EL Nino Southern Oscillation). For the period before this "turning point" we have made an exploratory investigation on the imprint of both SGAT and the solar activity (represented by the Sunspot Number - SSN) at delta O-18 isotopic ratios retrieved from ice cores, a proxy commonly used to describe past climate changes. In this work delta O-18 isotopic ratios, dated from 1861 to 1997, from three distinct global sites: (1) the Greenland Ice Sheet Project 2 (GISP2); (2) Quelccaya ice cap/Andes (Peru); and (1) Dronning Maud Land (DML)/ East Antarctica were investigated. The wavelet decomposition method and regressions applied to these databases successfully allowed the isotopic reconstructions from both SGAT and SSN. We found that the reconstructions differ significantly depending on the geographical site. (AU)

• Processo FAPESP: 18/21657-1 - Estudo da variabilidade da atividade auroral em rádio da magnetosfera de Júpiter
• Beneficiário: Ezequiel Echer
• Modalidade de apoio: Auxílio à Pesquisa - Regular