  Solar atmosphere is a single system unified by the presence of large-scale
magnetic fields. Topological changes in magnetic fields that occur in one place
may have consequences for coronal heating and eruptions for other, even remote
locations. Coronal magnetic fields also play role in transport of magnetic
helicity from Sun's subphotosphere/upper convection zone to the interplanetary
space. We discuss observational evidence pertinent to some aspects of the solar
corona being a global interconnected system, i.e., large-scale coronal heating
due to new flux emergence, eruption of chromospheric filament resulting from
changes in magnetic topology triggered by new flux emergence, sunspots rotation
as manifestation of transport of helicity through the photosphere, and
potential consequences of re-distribution of energy from solar luminosity to
the dynamo for solar cycle variations of solar irradiance.
