On the Characteristics of Astronomical Refraction in the Northern Hemisphere
Abstract
The paper considers the characteristics of astronomical refraction in the Northern Hemisphere. The refraction depends on the vertical structure or the height profile of atmospheric density. The fitness of the exponential representation of atmospheric density was examined and numerical experiments for astronomical refraction are discussed showing that a two spheres model expresses the best approach to the actual seasonal variation of surface pressure. The characteristics of astronomical refraction in the Northern Hemisphere were determined with aerological data obtained at standard pressure levels showing that the distribution of the mean density of the stratosphere corresponding to the equivalent density in the stratosphere shows two lower regions in Bering Sea and the Northwest Territory in Canada. Correction methods for astronomical refraction by adding a term for the total mass of the atmosphere and by using this term common to the vertical and horizontal gradient effects are described.
- Publication:
-
Refractional Influences in Astrometry and Geodesy
- Pub Date:
- 1979
- Bibcode:
- 1979IAUS...89..103S
- Keywords:
-
- Atmospheric Density;
- Atmospheric Refraction;
- Exponential Functions;
- Northern Hemisphere;
- Refractivity;
- Aerology;
- Atmospheric Pressure;
- Atmospheric Stratification;
- Stratosphere;
- Temperature Inversions;
- Tropopause;
- Vertical Distribution;
- Astronomy