seminar

[Joe Niemela]

Subject: Last minute seminar!


Title: Transitional solar dynamics, cosmic rays and global warming


A. Bershadskii

ICAR, Israel

Venue: Oppenheimer Room

Time: TODAY @ 15:30


Abstract:

Solar activity is studied using a cluster analysis of the
time-fluctuations of the sunspot number. It is shown that in Historic
period the high activity components of the solar cycles exhibit strong
clustering, whereas in a Modern period (last seven solar cycles: 
1933-2007) they
exhibit a white-noise(non-)clustering behavior. Using this observation it
is shown, that in the Historic period emergence
of the sunspots in the solar photosphere was strongly dominated by
turbulent photospheric convection.
In the Modern period, this domination was broken by a new more active
dynamics of the inner layers of the convection zone. Then, it is shown
that the dramatic change of the sun dynamics at the
transitional period (between the Historic and Modern periods, solar cycle
1933-1944yy) had clear detectable impact on Earth climate. A scenario of a
chain of transitions in the solar convective zone
is suggested in order to explain the observations, and a forecast for the
global warming is suggested on the basis of this scenario. Relation
between the recent transitions and solar long-period chaotic
dynamics has been found. Contribution of the galactic turbulence (due to
galactic cosmic rays) has been discussed. These results are also
considered in a content of chaotic climate dynamics at
millennial timescales.