A statistical analysis of data on monthly and seasonal values of air temperature and precipitation in Tbilisi from 1844 to 2018 was carried out. Trends of air temperature and precipitation in three period of year (year, cold and warm seasons) for 175 year observations is study. Comparison of monthly and seasonal mean values of air temperature and precipitations in two thirty years of time (1844-1873 and 1989-2018) was carried out. In particular, it was found that in the indicated periods of time there is a significance increase in air temperature for all months of the year, except May and November. As for precipitation, their growth is observed in October and November, and a decrease in July and September.

The data of ground-based (Prec_MS) and satellite (Prec_Sat) measurements of the monthly sum of atmospheric precipitation are compared using the example of Tbilisi in 2001-2020. In particular, the following results are obtained. In general, for all observational data (240 months), Prec_MS values vary from 0 to 267.3 mm, and Prec_Sat - from 3.0 to 184.0 mm. Their average values are 43.6 and 64.8 mm, respectively. Monthly mean values of Prec_MS vary from 16.7 mm (January) to 93.2 mm (May) and Prec_Sat values – from 32.5 mm (December) to 114.4 mm (May). Ground-based measurements are lower than satellite data for all months of the year. The difference between the average values of Prec_MS and Prec_Sat over 20 years varies from -8.8 mm (November) to -33.4 mm (March). Ratio between the average values of Prec_MS and Prec_Sat varies from 40.6 % (January) to 81.5 % (May). There is a direct linear correlation between the studied parameters. For all observational data (240 months) coefficient of correlation is 0.86 (high correlation), for separate month changes from 0.65 (July, moderate correlation) to 0.94 (April, very high correlation). Coefficient of correlation between average values of the studied parameters is 0.97 (very high correlation).

In Tbilisi according to the data of the complex monitoring of light ions concentration, radon and sub-micron aerosols the effect of feedback of intensity of ionizing radiation with the light ions content in atmosphere is discovered.

Preliminary results of the study of the relationship between the variability of the mean annual sum of atmospheric precipitation and landslide processes in Georgia for 32 years are presented. In particular, it was found that with an increase in the annual sum of atmospheric precipitation, the tendency of increase in the number of landslides is observed in accordance with a second power of polynomial