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Fleig, A. J.

Publications and source records attributed to Fleig, A. J..

28 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Results and analyses of ground-based and satellite ozone observations A review

The ground-based network that has been in existence for several decades is described. Attention is given to two basic questions, namely the way in which monthly satellite analyses compare with those from the ground-based network and the way in which the trends from the satellite and ground-based data compare. Synoptic analyses of total ozone for December 1970 are compared with a subjective analysis of the ground-based network and an objective backscatter ultraviolet (BUV) analysis. It is found that the BUV analysis is the more consistent of the two. Considering monthly analyses for September 1970, satellite and ground-based data are found to agree quite well. In considering the question of trend determination by the ground-based versus the satellite systems, attention is given to the sources of error in the satellite system. The principal sources of error in BUV analysis are thought to be calibration drift with time and the fact that, over the lifetime of the satellite spacecraft, power limitations result in a decrease in the number of data points per month, possibly with significant gaps in the coverage.

Miller, A. J.↗
NASA NTRS1981

First results from the Nimbus 7 total ozone mapping spectrometer

The Total Ozone Mapping Spectrometer (TOMS) instrument was launched on the Nimbus 7 satellite in October 1978. This instrument is designed to measure spatial variations in the total ozone field. The employed technique is an extension of the Backscattered Ultraviolet (BUV) total ozone method. The TOMS instrument has an improved capability for detailed monitoring of total ozone. The obtained data appear to contain information about dynamical processes in the upper troposphere and the lower stratosphere. Investigations are being conducted to determine qualitatively the conditions, if any, where total ozone fails as a predictor for tropopause height. Quantitative relations between the dynamic parameters and total ozone are also being studied.

Krueger, A. J.↗
NASA NTRS1981

Vertical ozone profile results from the Nimbus-4 BUV data

A seven year data set which consists of both total ozone and ozone vertical profiles has been derived from the Nimbus-4 Backscatter Ultraviolet (BUV) experiment. The BUV experiment measures the earth's backscattered solar radiance at 12 wavelengths in the Hartley-Huggins band. The shortest 8 bands are used to determine the vertical ozone profile. The longest four bands are used to determine the total ozone. The present investigation provides a review of the major characteristics of the instrument performance and ozone results during the seven year period of the data set. Attention is given to the data coverage in time and space, the major areas of nonhomogeneous coverage, adjustments made to the basic instrument radiances, long-term trends in the radiances, rocket and balloon measurements, and problems associated with the validation of the satellite data set.

Fleig, A. J.↗
NASA NTRS1981

Algorithm for vertical ozone profile determination for the Nimbus-4 BUV data set

A description is provided of the algorithm used by the Ozone Processing Team at NASA to process seven years of Backscatter Ultraviolet (BUV) ozone profile data. The algorithm is a modification of the original retrieval algorithm developed by Mateer (1972) to process some of the early data from the BUV experiment. Principal changes made are in the first guess selection scheme, the use of all wavelengths in the inversion, and the weighting of the various wavelengths according to the errors in the radiance estimation. It is found that the described BUV ozone profile algorithm is an extremely efficient algorithm for retrieving large amounts of satellite data. The algorithm makes full use of all the available information from the measured radiances including the longer wavelength radiances which previously had not been used.

Bhartia, P. K.↗
NASA NTRS1980

Satellite ozone measurements

Since 1960 three classes of zone sounders have been developed: (1) backscatter ultraviolet, (2) infrared limb and nadir radiance, and (3) stellar and solar occultation methods. With these techniques ozone has been measured from 20 to 100 km. Tropospheric ozone measurements are beyond present technology, but total ozone is determined with the backscatter ultraviolet and nadir infrared methods.

Krueger, A. J.↗
NASA NTRS1980

Role of multiple scattering in ozone profile retrieval from satellite measurements in the ultraviolet

The retrieval of the ozone profile from satellite ultraviolet measurements can be extended to greater depths when multiple scattering is taken into account. The sensitivity of the multiple-scattered wavelength radiances to geophysical variables are discussed and results of profile inversions of Nimbus 4 backscatter ultraviolet data for coincident ground-truth measurements with and without multiple scattering are presented.

Taylor, S. L.↗
NASA NTRS1978

Verification of Nimbus 4 BUV total ozone data and the requirements for operational satellite monitoring

Data obtained from the backscattering ultraviolet instrument on Nimbus 4 are compared with standardized observations such as ground based Dobson and M83 measurements. Results of the comparison are discussed and their impact on planning for a satellite ozone monitoring program is assessed. It is suggested that the satellite data be used as a transfer standard whereby, if a discrepancy in an individual ground station is detected, that station instrument would be noted for recalibration.

Miller, A. J.↗
NASA NTRS1972

Automated detection of bacteria in urine

A method for detecting the presence of bacteria in urine was developed which utilizes the bioluminescent reaction of adenosine triphosphate with luciferin and luciferase derived from the tails of fireflies. The method was derived from work on extraterrestrial life detection. A device was developed which completely automates the assay process.

Fleig, A. J.↗