Title: Tropospheric ozone trends from harmonized ground-based measurements
Speaker: Roeland Van Malderen, KMI-IRM
Abstract: Tropospheric ozone is a greenhouse gas and pollutant detrimental to human health and crop and ecosystem productivity. Tropospheric ozone is extremely difficult to monitor on the global scale due to its highly variable distribution and interannual variability. Quantification and attribution of long-term tropospheric ozone trends are critical for understanding the impact of human activity and climate change on atmospheric chemistry, but are also challenged by the limited coverage of long-term ozone observations in the free troposphere. An international effort and activity, Tropospheric Ozone Assessment Report (TOAR), was initiated 10 years ago, to produce an up-to-date scientific assessment of tropospheric ozone’s global distribution and trends from the surface to the tropopause. Its second phase, TOAR-II (2020-2024), has been organized along Focus Working Groups. One such Focus Working Group aimed at Harmonizing and Evaluating Ground-based Instruments for Free-Tropospheric Ozone Measurements (HEGIFTOM) for 5 different networks of instruments.
In this seminar, we report on the most important findings of this HEGIFTOM Focus Working Group and we present the tropospheric ozone distribution, inter-technique comparisons, individual-site and regional tropospheric ozone trends. In particular, we will also assess the impact of the COVID-19 restrictions on the tropospheric ozone distribution and (post-COVID) trends.
Time and place: Februari 5, 2025 - 14:00 - RMI conference room
