Remote Sounding of Atmospheric Temperature Profiles Using the Optical Measure Method
Abstract
This report describes an exploratory investigation on the applicability of the Optical Measure Method (OMM) to the retrieval of atmospheric temperature profiles using both the simulated and HIRS-2 radiances. The basic theory is presented for the OMM. Then described are the synthetic retrieval of temperature profiles using HIRS-2 derived from both polynomial and polynomial-hyperbolic functional fitting of radiances are poor. Two major sources of errors are identified through a forward analysis. One is the variation in the sharpness index of the weighting function with sounding channels, while the other is the surface contribution to radiances. For these reasons, an adjustment scheme has been developed using the concept of scaling factors , which encompasses the effects of variation in the sharpness index, surface discontinuity, channel properties, and functional forms. Retrieved temperature profiles derived from polynomial-hyperbolic functional fitting of adjusted radiances are much improved. The Differential Inversion Method (DIM) for temperature retrieval and OMM are mathematically equivalent. In practice, the DIM works better because of the fitting of radiances in the logarithmic pressure scale, which accounts for some of the surface contribution. Application of the DIM to an archive of 3473 collocated temperatures is within about 3 K below 250 mb. In order to obtain a better accuracy, modifications and refinements are required for the DIM.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 31, 1989
- Accession Number
- ADA244828
Entities
People
- K. N. Liou
- S. C. Ou
Organizations
- University of Utah