Geophysical processes and biosphere: article

Аnnotation: Quantitative indicators of the influence of the shape of the Earth (ellipsoidal with modern polar compression or spherical) on the characteristics of its irradiation, calculated without taking into account changes in solar activity, are obtained. Differences in the specific radiation energies (J/m2), as well as the radiation intensities (W/m2) of the ellipsoid and the sphere and their parts in average for the tropical year and in its parts (half-years, months) are calculated. According to the Earth’s movement data for tropical years from 3000 BC to AD 2999 it was revealed that at a constant intensity of solar radiation, each of the two annual irradiation characteristics of the sphere is 0.085 % higher than one of the ellipsoid. The monthly specific radiation energy for the sphere is almost constant, and for the ellipsoid it varies with a spread of 0.043 % of the average value (minima at the equinoxes, maxima at the solstices). The monthly irradiation intensities for a sphere and an ellipsoid change synchronously with a spread of 5.98 % of the average value (minimum at the 3rd month, maximum at the 9th). The hemisphere seasonality in terms of specific radiation energy (modulus of difference between half-years specific radiation energies for hemisphere) in case of the ellipsoidal Earth is on average 0.223 % higher than one in case of the spherical Earth. Among the differences in the semi-annual specific radiation energies (and similarly in the semi-annual radiation intensities) of the latitudinal zones of the sphere and ellipsoid, the maximum is positive and the minimum is negative. At the first half of the year, the maximum and minimum are observed in the zones of 45º-50º S and 10º-15º N. At the second half of the year the maximum and minimum are observed in the zones of 45º-50º N and 10º-15º S. According to the data for 1978-2008 it was revealed that the differences in the intensities of irradiation of sphere and ellipsoid are comparable with the variations of total solar irradiance (TSI) associated with changes in solar activity. The average absolute value of the annual TSI anomaly is 14.01 % more than the average annual difference in the intensities of irradiation of a sphere and an ellipsoid. The average absolute value of the monthly TSI anomaly exceeds the average monthly difference of the irradiation intensities of the sphere and ellipsoid by 23.37 %.