Atmospheric Refraction Measurements and Related Efforts
Abstract
The ETMG task on refraction correction was originated with the optimistic goal of definitively dissecting the refraction problem, establishing those accomplishments which are possible and recommending equipments and techniques to be used for various situations. Since the atmosphere is a continually varying medium, even perfect measurements of refractivity in a given location may not be valid for a nearby region, and shortly after measurement will no longer be valid for the region measured. Rawinsonde or refractometer measurements typically involve the instrument being borne over a long distance during a considerable time period. The normal assumptions that the derived refractivity profile is both spherically symmetric and invariant in time undoubtedly introduce gross errors into any correction technique. It was decided to begin the refraction study by adopting the questionable symmetric and invariant assumptions, and assuming that the only error in making a correction for the refraction effect is introduced by errors in measurement of the refractivity profile. That profile measurement is assumed to be made by the most typically used instrument, the rawinsonde. If good results are possible under these assumptions, then the sensitivity to relaxation of the questionable assumptions could be made.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1979
- Accession Number
- ADA065766