Cosmic rays as main factor of influence of solar variability on climatic and atmospheric parameters

Analysis of experimental data demonstrates that cosmic ray enhancement stim ulates an increase of atmospheric aerosoles and cloudiness. The study of so lar proton events (SIZE) has shown that during SPE one can observe increase in aerosole density by 1,4-1,8 times at 12-18 km altitudes. Such variation s of aerosole density can be detected on global scale. aerosole variations cause changes in integral atmospheric transparency which during disturbed p eriods can reach 5-6%. The atmospheric integral transparency variations are not; less during the solar cycle on account of galactic cosmic ray variati ons. Atmospheric transparency variations creating the so-called <<grey filt er>> for solar radiation should lead to surface temperature variations, Dur ing the periods of low solar activity under the influence of enhanced galac tic cosmic ray fluxes, the density of the <<grey filter>> should increase a nd cause a decrease in surface temperatures, correspondingly. In frame of t he physical mechanism considered the connection between salar cycle duratio ns and surface temperature variations can be explained. In addition, one ca n understand the physical reason for the <<Little Ice Age>> appearance duri ng Maunder minimum of solar activity, 2400 years periodicity of climatic pr ocesses, strong influence of the decrease in main geomagnetic field intensi ty an the development of Ice Age and Global Cooling.