It has been shown that cosmic rays may affect the aggregate transitions of water in the free atmosphere
through ionization of air and, thereby, the atmospheric parameters. The pressure variations derived from
measurements of the water content across the atmosphere have been estimated. According to these
estimates, the magnitude of possible pressure variations caused by cosmic rays in the form of Forbush
decreases of galactic cosmic rays is 4.8 mbar. Data on the near-Earth pressure at three considerably
distant points (Moscow, Apatity, and Yakutsk) have been analyzed in order to prove this effect. It follows
from an analysis that the effect of galactic cosmic rays on the atmosphere is simultaneously observed at
least in polar and middle latitude regions of the Earth.