More than three years of GOME-2 vertical ozone profile data is available and has been validated against ozonesonde data, which has a vertical resolution of about 100 m and is measuring ozone from the surface up to about 30 km.
GOME-2 vertical ozone profiles are given as partial ozone columns [in DU per layer] between varying pressure levels (40 levels between surface and 0.01 hPa). To validate the satellite derived ozone layers with the ozonesonde data, we integrate the ozone measured by the balloon ozone soundings between the corresponding GOME-2 pressure levels.
GOME-2 ozone data was made available by KNMI at pre-selected sites. The reference data includes a global coverage of ozonesonde stations.
The results show that the mean relative difference between GOME-2 and mid-latitude ozonesondes is within ±10 % in the troposphere and the stratosphere. The high latitude stations give poorer results: the mean relative difference between GOME-2 and ozonesondes is within ±15 % in the troposphere and the stratosphere. The bias is larger in the UTLS region, especially at high latitudes. The standard deviation on the mean difference is of the order of 30% in the troposphere and 10 to 15% in the stratosphere at mid-latitudes. In the UTLS region, the standard deviation on the mean is considerably larger.
We take into account the GOME-2 averaging kernels in our analysis in order to smooth the ozonesonde data towards the resolution of the satellite data.
In preparation of a future processor upgrade, also high-resolution ground pixels (80 x 40 km) have been processed and validation results are shown.
A Delcloo, ONE Tuinder. Validation of GOME-2 Ozone Profiles, using balloon sounding data