Background: A man is constantly exposed to numerous environmental factors, including meteorological conditions of the earth and space weather. The study of human health effects of these factors is of increasing interest both for science and practice. Objective: To compare instrumental and computational methods for assessing the Earth’s magnetic field in selected territories for further identification of priority natural and climatic factors and development of region-specific measures for adaptation of the local population to climate change, which should be taken into account when conducting social and hygienic monitoring. Methods: Instrumental measurements of the Earth’s magnetic field strength were carried out on the territories of the Moscow, Voronezh, Rostov, and Krasnodar regions of the Russian Federation, in August 2020. The total number of measurements was at least 15 at each point. The studies were conducted in accordance with the existing approved standard. Results and discussion: The territories for the study were selected taking into account changes in the latitude of the area, which has a priority importance in the formation of natural and climatic conditions of these regions. During the research, it was found that there was no significant difference in the values of the Earth’s magnetic field strength during the day and at night, which is associated with the main error of the device (MTM-01 three-component magnetometer). The obtained instrumental values of the magnetic field strength index ranged from 37.1 to 40.51 A/m. When analyzing the results obtained, there is a tendency to increase the intensity of the Earth’s magnetic field in the direction from South to North (Krasnodar Territory, Rostov, Voronezh, Moscow regions). The range of calculated values of the intensity indicator was from 39.9 to 42.19 A/m. The obtained instrumental data correlate with the calculated values of the Earth’s magnetic field. Conclusions: We conducted instrumental studies complying with existing models for estimating the Earth’s magnetic field strength, thus enabling application of our estimates in scientific research.