Аннотация:Using the events in July 2005 as an example, the causes and
peculiarities of Forbush effects produced by solar sources remote from
the central zone are discussed. The event in question differs from other
effects observed at the periphery of interplanetary disturbances by
strong variations in cosmic rays on the background of weak disturbances
in the solar wind and magnetic field of the Earth. The cloud of
magnetized plasma ejected from the Sun was large and fast, but it passed
to the west from the Sun-Earth line. According to performed estimates,
the mass of the ejected substance was close to the upper boundary of
mass for coronal mass ejections (CMEs). Anomalous parameters and high
modulation capability of the formed solar wind disturbance are
explained, in particular, by the fact that it combined several CMEs and
that the last fast disturbance was prepared by a series of impulsive
events in the active region of the Sun. Usually, such a great mass is
ejected directly after the main energy release in strong solar flares.
In the given case, a powerful MHD disturbance occurred approximately
half an hour after a maximum of hard X-ray burst under the conditions
when gas pressure in the flare loops became close to magnetic pressure,
which was just a premise of the largescale ejection.