Title: New Evidence of Space Weather Impact on the Terrestrial Weather
and Climate in the Earth's Southern Hemisphere
Author: Walther N. Spjeldvik
Affil: Weber State University
Email: wspjeldvik@cc.weber.edu
Authors: A. Almeida, A. Gusev, I. M. Martin, G. Pugacheva
Affils: Instituto Nacional de Pesquisas Espaciais, INPE, Sao Jose Dos Campos, SP, Brazil;
2 Instituto de Fisica and University of Campinas, SP, Brazil
A. Almeida(1), A. Gusev(2), I. M. Martin(1), G. Pugacheva(1,2) and W. N. Spjeldvik(3)
1 Instituto Nacional de Pesquisas Espaciais, INPE, Sao Jose dos Campos, SP, Brazil; 2 Instituto de Fisica, University of Campinas, SP, Brazil; 3 Department of Physics, Weber State University, Ogden, UT 84408, USA
Abstract: Data on liquid precipitation in Brazil for three
meteorological stations (Station Pelotas: 31deg 45min S, 52deg 21min
W; Station Campinas: 22deg 53min S, 47deg 04min W; Station Fortaleza:
3deg 45min S, 38deg 31min W) covering all of the latitudinal range of
Brazil from year 1849 up to 2000 were considered. Periodic analysis
of the annual rainfall level shows a pronounced 22-year periodicity
for several littoral regions. The amplitude of the variation reaches
90%. The best correlation with a 22-year solar magnetic field cycle
is obtained with the assumption that the phase of the correlation is
changed once during the whole 150 years period of observations at
Fortaleza and during the 100 years period of observations at Pelotas.
In the equatorial station Fortaleza the correlation coefficients
between the solar activity cycle and the rainfall pattern are -77%
4%
during 1849-1940 and +80.04% during 1952-2000 (showing
the phase change), and in the south-middle latitude station Pelotas
60%13% in 1893-1920 and -84%pm4% from 1929 up to 2000
reaching even more than 90% during the time intervals 1928-1939;
1948-1959; 1970-1981. We find that the phase of the space weather
versus terrestrial weather correlation is different and even opposite
for the various latitudinal regions, and this suggest a long term (>
100 years) latitudinal pattern shift superimposed on the time scale
of the 22-year solar activity cycle. The phase change is found to
have occurred mostly during the even 16th and 18th solar cycles,
first recoded at the higher latitudes, and later discerned in the
equatorial region. Additionally, the rainfall time series also
demonstrates a 52% correlation with an apparent 24-year periodicity
that is possibly connected with the atmosphere-ocean coupling; and
this feature is without any suggestion about any phase change in the
time series. Specific analysis of short-term rainfall variations
shows a significant increase in rainfall level several days after
solar magnetic sector boundary (MSB)! crossing detected by Earth
orbiting spacecraft. This additional finding is an argument in favor
of existence of physical link between rainfall variations and the
solar magnetic activity cycle. The results presented herein appear
to have bearing both as a scientific instrument for the unmasking of
the sun-weather connection problem, and may possibly have
significance for long term practical weather forecasting in the South
American region and elsewhere.