Speaker
Description
Observations in limb geometry from satellite platforms provide information with high spatial and temporal coverage and a good vertical resolution. Ozone profiles from SCIAMACHY (2002-2012) and OMPS-LP onboard Suomi-NPP (2012-present) have been retrieved at the University of Bremen using the same radiative transfer model, spectroscopic databases and a similar retrieval algorithm. Within the current CCI project, we have started the retrieval of OMPS-LP onboard NOAA-21, which was lunch at the end of 2022.
The SCIAMACHY and OMPS-LP data sets have been merged, to obtain a consistent time series of ozone global distributions. The final plan is to include in the merged data set also the observations from the sensor onboard NOAA-21. This will extend the data set into the 2030s, when also ALTIUS data are expected to be available.
For the merging, because of the short overlap of the two missions, measurements performed by the MLS instrument have been used as a transfer function, to provide a statistically significant bias estimate. Monthly latitude- and longitude-resolved time series of ozone profiles were calculated, exploiting the high spatial resolution of the data sets. We then use this merged data set to study long-term ozone changes: a multi-linear regression model was applied over the 2003-2023 period, including fit proxies to account for QBO, ENSO, solar forcing and stratospheric dynamics. We explore zonally averaged and longitudinally resolved trends.
