Sunspot cycles and Grand Minima
نویسندگان
چکیده
منابع مشابه
Origin of grand minima in sunspot cycles.
One of the most striking aspects of the 11-year sunspot cycle is that there have been times in the past when some cycles went missing, a most well-known example of this being the Maunder minimum during 1645-1715. Analyses of cosmogenic isotopes ((14)C and (10)Be) indicated that there were about 27 grand minima in the last 11,000 yrs, implying that about 2.7% of the solar cycles had conditions a...
متن کاملGrand minima and equatorial symmetry breaking in axisymmetric dynamo models
Weconsider themanner inwhich time-periodic solutions of an axisymmetric dynamo model can undergo breaking of equatorial symmetry, i.e. loss of pure dipolar or quadrupolar symmetry. By considering the symmetry group underlying the solutions, we show that the fluctuations responsible for the symmetry-breaking can be constrained such that they are in resonance with the former solution. They can th...
متن کاملSolar Grand Minima and Random Fluctuations in Dynamo Parameters
We consider to what extent the long-term dynamics of cyclic solar activity in the form of Grand Minima can be associated with random fluctuations of the parameters governing the solar dynamo. We consider fluctuations of the alpha coefficient in the conventional Parker migratory dynamo, and also in slightly more sophisticated dynamo models, and demonstrate that they can mimic the gross features ...
متن کاملGrand minima and maxima of solar activity: New observational constraints
Aims. Using a reconstruction of sunspot numbers stretching over multiple millennia, we analyze the statistics of the occurrence of grand minima and maxima and set new observational constraints on long-term solar and stellar dynamo models. Methods. We present an updated reconstruction of sunspot number over multiple millennia, from C data by means of a physics-based model, using an updated model...
متن کاملGrand Minima of Solar Activity and the Mean-Field Dynamo
We demonstrate that a simple solar dynamo model, in the form of a Parker migratory dynamo with random fluctuations of the dynamo governing parameters and algebraic saturation of dynamo action, can at least qualitatively reproduce all the basic features of solar Grand Minima as they are known from direct and indirect data. In particular, the model successfully reproduces such features as an abru...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Proceedings of the International Astronomical Union
سال: 2009
ISSN: 1743-9213,1743-9221
DOI: 10.1017/s1743921309992511