Abstract:
In this paper, we explore the evolution of sunspot latitude distribution and explore its relations with the cycle
strength. With the progress of the solar cycle, the distributions in two hemispheres from mid-latitudes propagate
toward the equator and then
(
before the usual solar minimum
)
these two distributions touch each other. By
visualizing the evolution of the distributions in two hemispheres, we separate the solar cycles by excluding this
hemispheric overlap. From these isolated solar cycles in two hemispheres, we generate latitude distributions for
each cycle, starting from cycle 8 to cycle 23. We
fi
nd that the parameters of these distributions, namely the central
latitude
(
C
)
, width
(
δ
)
, and height
(
H
)
, evolve with the cycle number, and they show some hemispheric
asymmetries. Although the asymmetries in these parameters persist for a few successive cycles, they get corrected
within a few cycles, and the new asymmetries appear again. In agreement with the previous study, we
fi
nd that
distribution parameters are correlated with the strengths of the cycles, although these correlations are signi
fi
cantly
different in two hemispheres. The general trend features, i.e.,
(
i
)
stronger cycles that begin sunspot eruptions at
relatively higher latitudes, and
(
ii
)
stronger cycles that have wider bands of sunspot emergence latitudes, are
con
fi
rmed when combining the data from two hemispheres. We explore these features using a
fl
ux transport
dynamo model with stochastic
fl
uctuations. We
fi
nd that these features are correctly reproduced in this model. The
solar cycle evolution of the distribution center is also in good agreement with observations. Possible explanations
of the observed features based on this dynamo model are presented.
