A paper published today in the Journal of Atmospheric and Solar-Terrestrial Physics finds that sunspot numbers and the assumption of natural climate cycles “accurately reproduces” the patterns of rainfall in Fortaleza, Brasil “over the entire 160 years of observations.”
Possible evidence of the resonant influence of solar forcing on the climate system
A.A. Guseva, , , I.M. Martinb
a IKI RAS, 84/32 Profsoyuznaya Str, 117997 Moscow, Russia
b UNITAU, 432 rua 04 de Março, 12020-270 Taubate, SP, Brazil
Received 20 June 2011. Revised 15 January 2012. Accepted 22 January 2012. Available online 31 January 2012.
http://dx.doi.org/10.1016/j.jastp.2012.01.008, How to Cite or Link Using DOI
An assumption of the existence of natural climatic oscillations driven by solar activity enables an explanation of phase differences between variations in solar activity and rainfall level in Fortaleza, Brazil. Decadal and interdecadal variations in rainfall level can be reproduced using a forced oscillation equation with a driving force term that describes the variation in the sunspot number and with the assumption of the existence of 31.7-year interdecadal and 12.96-year decadal natural climatic oscillations. This equation satisfactorily reproduces the periodicity with a length of approximately 22 yr in the interdecadal rainfall variation before and up to the middle of the past century as well as the subsequent phase inversion, period and amplitude increase in the variation that followed the corresponding increases in the interdecadal sunspot number variation. The equation accurately reproduces the irregular phase shifts between decadal variations in rainfall level and in sunspot number over the entire 160 yr of recorded observations.