Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10701012 | Chinese Astronomy and Astrophysics | 2005 | 11 Pages |
Abstract
The Abel integral transformation in GPS/LEO occultation technique requires the atmospheric index of refraction n to be a single-valued function of the refractional radius a. This condition is broken when the vertical refractivity gradient is less than a critical value dN/drâ¼-0.16 N-units mâ1, and it is called superrefraction. The Abel integral transformation is no longer valid under this condition, and, if the classical Abel transformation is still formally applied, then a negative refractivity bias occurs in results. The physical characteristics and mathematical expression of the superrefraction phenomenon in the lower troposphere are described. In the frame of a general Abel integral transformation, the inversion algorithm of the atmospheric profiles in and below the superrefraction layer is discussed. Under a simple assumption of the constant vertical gradient of refractivity in the sampling interval, the simulation calculation is carried out on UK High Resolution Radiosonde Data. The computational results have verified the relationship between the negative refractivity bias and the superrefraction phenomenon, as well as the validity of the general Abel transformation proposed.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Astronomy and Astrophysics
Authors
Yan Hao-jian, Guo Peng, Hong Zhen-jie, Liu Min,