Sources of solar wind over the solar activity cycle

Sources of solar wind over the solar activity cycle

Fast solar wind has been recognized, about 40 years ago, to originate in polar coronal holes (CHs), that, since then, have been identified with sources of recurrent high speed wind streams. As of today, however, there is no general consensus about whether there are, within CHs, preferential locations where the solar wind is accelerated. Knowledge of slow wind sources is far from complete as wel...

Does the solar wind affect the solar cycle ?

We calculated the change of the magnetic flux through the surface encircled by the Earth’s orbit. This change is associated with the magnetic flux transfer by the solar wind flow and exhibits clear 22-year periodicity. The magnetic flux transferred by the solar wind is of the same order of magnitude as the flux of the main solar magnetic field through the northern hemisphere of the Sun. There s...

Solar cycle variations of solar wind dynamics and structures

This paper reviews solar cycle variations in the heliosphere. We show that some solar cycle changes, such as the correlation between speed and density, result from the evolution of the solar structure from dipolar with strong latitudinal gradients at solar minimum to a disordered field with little latitudinal variation at solar maximum. Other changes, such as the variation of the solar wind dyn...

Solar cycle dependence of scaling in solar wind fluctuations

In this review we collate recent results for the statistical scaling properties of fluctuations in the solar wind with a view to synthesizing two descriptions: that of evolving MHD turbulence and that of a scaling signature of coronal origin that passively propagates with the solar wind. The scenario that emerges is that of coexistent signatures which map onto the well known “two component” pic...

Solar Wind Composition Associated with the Solar Activity