Search NASASearch

Engineering topics

Rogers, T. G.

Publications and source records attributed to Rogers, T. G..

Ozone climatology series. Volume 1: Atlas of total ozone, April 1970 - December 1976

Contours and gridded values are given for seven years of monthly mean total ozone data derived from observations with the Backscattered Ultraviolet instrument on Nimbus-4 for the Northern and Southern Hemispheres. The instrument, algorithm, uncertainties in derived ozone and systematic changes in the bias with respect to the international groundbased ozone network of Dobson instruments, are discussed.

Heath, D. F.

Total ozone variations 1970-74 using Backscattered Ultraviolet /BUV/ and ground-based observations

The most long-lived satellite set of ozone observations, to date, is that derived from the Backscatter Ultraviolet (BUV) ozone sensor on Nimbus 4 and extends from April 1970 through 1976. Unfortunately, this experiment suffered spacecraft power limitations which limited the spatial and temporal coverage and also appears to have suffered from long-term drifts which may be associated with changes in the instrument characteristics or the incident solar flux. Techniques have been developed to account for these problems, and this paper presents results of the BUV total ozone variations and compares them with those from ground-based observations, specifically the computations of Angell and Korshover (1978). After adjustments for the spatial gaps and comparison with concurrent Dobson ground-based observations, no significant trend was found in the BUV data over the years 1970-74. This finding is in contrast to a general decrease of about 2% during the same period appearing in the data of Angell and Korshover. The difference in these results is discussed in terms of the geographic sampling and the methods of hemispheric integration.

Miller, A. J.

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.