The Hub Talks: The TROPOMI Ozone Profile Retrieval Algorithm: Status and Improvements for Tropospheric Ozone Detection

Name: The Hub Talks: The TROPOMI Ozone Profile Retrieval Algorithm: Status and Improvements for Tropospheric Ozone Detection
Start: 2026-10-01T15:00:00+02:00
End: 2026-10-01T16:00:00+02:00

October 1 @ 3:00 pm – 4:00 pm CEST

Speaker: Serena Di Pede, KNMI (Royal Netherlands Meteorological Institute)

Short Bio: Serena Di Pede is a Researcher at KNMI (Royal Netherlands Meteorological Institute), where she has been part of the L2 retrieval team since 2022, working on
the operational ozone profile retrieval algorithm for the Sentinel-5P TROPOMI instrument. She also closely collaborates with the L1B team on the UV
radiometric calibration of TROPOMI’s input data. Since 2024, she is a PhD candidate in the Department of Geosciences and Remote Sensing at TU Delft,
applying the TROPOMI retrieval algorithm to tropospheric ozone studies over polluted areas in China as part of the ESA-MOST/NRSCC Dragon 6 Programme.
She studied Physics at the University of Bologna, with a Master’s degree in Nuclear and Subnuclear Physics

Abstract: Ozone is one of the most important trace gases in the Earth’s atmosphere. Its effects depend strongly on altitude: stratospheric ozone protects the biosphere from harmful UV radiation, while tropospheric ozone negatively impacts human health, ecosystems and agriculture, and acts as a significant anthropogenic greenhouse gas. In recent years, tropospheric ozone pollution has noticeably increased in several highly polluted regions worldwide. Because ozone concentrations and their evolution vary strongly by region and climate, daily global monitoring of the vertical ozone distribution is needed to understand its variability and transport across different scales.
The TROPOMI ozone profile retrieval offers a unique opportunity to study the global 3D ozone distribution at high horizontal spatial resolution (28 × 28 km²), resolving five to six independent vertical pieces of information (degrees of freedom, DFS). As expected for a nadir-viewing instrument, vertical sensitivity decreases toward the surface, making tropospheric ozone detection particularly challenging.
In this talk, I will present the current status of the TROPOMI ozone profile retrieval and discuss the efforts to enhance its sensitivity to tropospheric ozone. We focus on key aspects of the retrieval chain, including the radiometric calibration of the input spectra, the treatment of measurement noise, and the choice of a priori ozone profile information. We show how refining these elements improves the information content and the overall quality of the retrieved product, particularly in the lowest layers of the atmosphere.