O3 profiles from GOME satellite data-I:: Comparison with ozonesonde measurements

Ozone profiles on a global scale can be derived from GOME satellite data by minimizing the difference between the measured and the corresponding simulated spectra as a function of the vertical distribution of O-3. For this purpose the FUII Retrieval Method (FURM) was developed, which is based on the optimal estimation approach and contains the radiative transfer code GOMETRAN as an essential component. The quality of the GOME ozone profiles is assessed by comparing them with 197 coincident ozonesonde measurements at five selected European stations. The comparison results show that the seasonal ozone variations are very well reproduced by the GOME profiles. The agreement between the GOME and the sonde measurements is best above 18 km altitude where the mean relative difference is below 10 % and the root mean square of the relative differences is of the order of 10%. Larger differences occur in the tropopause region and lowermost stratosphere where the natural ozone variability is largest. (C) 1999 Elsevier Science Ltd. All rights reserved.