Total Ozone Measuring Spectrometers TOMS

Krueger, A.J., L.S. Walter, P.K. Bhartia, C.C. Schnetzler, N.A. Krotkov, I. Sprod and G.J.S. Bluth (1995) Volcanic sulfur dioxide measurements from the total ozone mapping spectrometer (TOMS) instruments. Journal of Geophysical Research 100 14057-14076. 

Measurements of the gaseous sulfur dioxide released were obtained with the Total Ozone Mapping Spectrometer (TOMS Krueger, 1983) and with the Solar Backscatter Ultraviolet Spectrometer (SBUV Heath et d., 1983), both carried on the Nimbus 7 satellite. Three instruments on board the Solar Mesosphere Explorer (SME) also revealed features of the cloud the Infrared Radiometer measured the thermal emission from the aerosols, while the Visible and Near Infrared Spectrometers measured the backscat-tered solar radiation. The three instruments are limbscanning and view the atmosphere along the track of the sunsynchronous polar orbit (Barth et d., 1983 Thomas et d., 1983). Ground based and airborne spectro-photometric measurements of sulfur dioxide have also been carried out (Evans and Kerr, 1983). 

Krueger A. J., Walter L. S., Bhartia P. K., Schnetzler C. C., Krotkov N. A., Sprod I., and Bluth G. J. S. (1995) Volcanic sulfur dioxide measurements from the Total Ozone Mapping Spectrometer (TOMS) instruments. J. Geophys. Res. 100, 14057-14076. 

FIGURE 4-40 The Antarctic ozone hole, October 1991, as measured by the total ozone mapping spectrometer (TOMS) from the Nimbus 7 satellite. The hole covers the Antarctic continent and extends as far north as the tip of South America. (Reprinted with permission from R. Stolarski, R. Bojkov, L. Bishop, C. Zerefos, J. Staehelin, and J. Zawodny, 1992, Measured Trends in Stratospheric Ozone, Science 256 342-349. Copyright 1992, American Association for the Advancement of Science.)... 

FIGURE 7.3 Antarctic ozone minima. 1979-2003. The ozone minima are given above the data points and the dates of recorded minima are given below the data points. The data, in Dobson units (DU), were measured by the Total Ozone Mapping Spectrometer (TOMS) spacecraft. (Source http // jwocky.gsfc.nasa.gov/multi/ min ozone.gif)... 

Total Ozone Mapping Spectrometers (TOMS) measure solar irradiance and radiance backscattered by the earth s atmosphere at six wavelengths extending from approximately 310 to 380 nm. TOMS measurements can be used to estimate the tropospheric ozone amount by the calculation of the difference of total ozone minus stratospheric ozone amount measmed by another satellite instrument (SAGE Stratospheric Aerosol and Gas Experiment), in particular when stratospheric ozone variations are small, usually over the tropics. However, the residual tropospheric ozone calculation has some limitation in accuracy because the tropospheric ozone amount is calculated as a small difference of two large numbers (total and stratospheric ozone). Measurements of the TOMS instra-ment on Nimbus 7 satellite have been used to estimate tropical tropospheric ozone trends from 1978 to 1992. 

Figure 11.5 This diagram comes from NASA s ozone monitoring programme TOMS (Total Ozone Mapping Spectrometer). The ozone hole over the Antarctic (shown in purple and pink on the diagram) is largest in the Antarctic spring. Note Dobson Units are a measure of the total amount of ozone in a vertical column from the ground to the top of the atmosphere.

Since 1978 spectral measurements of sunlight backscattered from the Earth to the space have been made from satellites, starting with NASA s Nimbus-7 satellite with the TOMS (Total ozone mapping spectrometer) instrument. This spectrometer was designed to measure backscattered UVR at six wavelengths in the UV-B and UV-A and to derive total column ozone amount from these radiance data. This application is well established and the uncertainty is well... 

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