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Comparison of MLS stratospheric column ozone and TOMS total column ozone: implications of biomass burning
from Ziemke et al. [J. Geophys. Res., vol. 101, 14,421-14,427, 1996]


southern hemisphere map of TOMS ozone in September 1992 compared with a southern hemisphere map of MLS ozone for the same time period

The figures shown here, and analyses, were performed by Dr. Jerry Ziemke and colleagues at the NASA Goddard Space Flight Center, and are described in Ziemke et al. [J. Geophys. Res. vol. 101, 14,421-14,427, 1996]. The above figure shows anomaly fields of version 6 TOMS total column ozone (top panel) and MLS stratospheric column ozone (bottom panel) for September 1992. The anomalies were derived by first subtracting the monthly zonal mean from each time series of data binned in 5o latitude by 15o longitude cells, and then dividing the resulting values by the zonal mean. Values are shown in percent; contour intervals are 1% for percentages between -10% and +10%, and 2% for outside +/10%.

The TOMS total ozone (top panel in above figure) shows a clear zonal wave 1 structure that is out of phase between the tropics and extratropics. MLS column ozone anomalies (bottom panel in above figure) are seen to be nearly identical to TOMS in the middle and high latitudes. Although MLS stratospheric column ozone explains most zonal variability of TOMS wave 1 in high latitudes, the tropical wave 1 in TOMS is clearly not present in MLS and appears to be generally consistent with the SAGE results of Shiotani and Hasebe [J. Geophys. Res., vol 99, 14,575-14,584, 1994.] The indication from comparing the TOMS and MLS data is that the tropical wave 1 structure in total ozone originates from ozone below the levels measured by MLS.

The tropical wave 1 anomaly is observed in all seasons in total ozone from TOMS, but never seen in MLS stratospheric column ozone. This wave in TOMS and SBUV2 total ozone appears to be a permanent structure modulated by seasonal increases in Sep-Oct-Nov associated with intense biomass burning in Africa and South America around July-October each year. The figure below shows TOMS and MLS tropical anomalies for Mar-Apr-May (top panels) and Sep-Oct-Nov (bottom panels).

2 maps of TOMS ozone, one for MAM and one for SON compared with 2 map of MLS ozone for the same time period

For further discussing of these data and analyses see Ziemke et al. J. Geophys. Res. vol. 101, 14,421-14,427, 1996.

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