Sun-climate relationships studied in tree rings in Chile

• Grant number: 01/01569-0
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2001
• End date: April 30, 2002
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geophysics
• Principal Investigator: Daniel Jean Roger Nordemann
• Grantee: Daniel Jean Roger Nordemann
• Host Institution: Instituto Nacional de Pesquisas Espaciais (INPE). São José dos Campos , SP, Brazil
• City of the host institution: São José dos Campos

Abstract

This work aims to clarify the relationships that exist between the variation in sun luminosity associated with solar activity and environmental and climatic phenomena recorded in the variations of the thickness of the growth rings of trees. The scale of time chosen covers the last two millennia and the samples of trees used to obtain the temporal series of thickness of their rings are cypresses originating in Chile, given the fact that we can find in them series covering the desired interval of time. Thus, we will study the temporal series of the thickness of growth rings of trees sensitive to environmental parameters, such as temperatures and pluviometry, among others, and of pertinent observational data, such as the number of sunspots. The study comprises the mathematical analysis of the temporal series, searching for characteristic periodicities of geophysical and/or climatic phenomena. The methodology used includes spectral analysis through the methods of maximum entropy and iterative regression and principally through the method of wavelets. The study will be concentrated geographically on the records and observational data from Chile. (AU)