Serdecznie zapraszamy na wykład dr Tabish Ansari “Explaining Changes in Ground-Level Ozone Concentrations in North America, Europe, and the Arctic from 2000 to 2018.”

🗓️ 19 maja 2026 r. w godzinach od 11:30 do 13:00

Zapraszamy do audytorium Wydziału Nauk Geograficznych Uniwersytetu Kazimierza Wielkiego (UKW) w Bydgoszczy, lub dołączenia
online: LINK

Description:
Dr. Tabish Ansari earned his Ph.D. in atmospheric sciences from Lancaster University (United Kingdom) in 2020, specializing in the modeling and analysis of aerosol pollution sources. Previously, he completed his master’s degree in environmental engineering at IIT Madras in India. After completing his PhD, he worked at the University of Galway and the University of Groningen, among others, and has been affiliated with RIFS since 2022, where he focuses on global modeling of tropospheric ozone.

The lecture will focus on analyzing changes in ground-level ozone concentrations on a regional and intercontinental scale, as well as their main causes. Observed trends in North America, Europe, Asia, and the Arctic will be discussed, including seasonal variations and the impact of changes in ozone precursor emissions. The speaker will explain how various emission sources (transportation, industry, wildfires, natural and stratospheric emissions) affect air quality, using the global CAM-Chem model and ozone source tracing techniques.
Attending the lecture will be an opportunity to learn about the mechanisms of global pollutant transport, modern methods of atmospheric research, and current climate challenges through direct interaction with an expert in the field.

Abstract:
Surface ozone, with its long enough lifetime, can travel far from its precursor emissions, affecting human health, vegetation, and ecosystems on an intercontinental scale. Recent decades have seen significant shifts in ozone precursor emissions: reductions in North America and Europe, increases in Asia, and a steady rise in global methane. Observations from North America and Europe show declining ozone trends, a flattened seasonal cycle, a shift in peak ozone from summer to spring, but steadily increasing wintertime levels. Observed ozone in China and India generally shows increasing trends.

In my talk, I will explain these changes in regional ozone in different world regions in terms of contributions from its precursor emissions from different sectors and regions (domestic, foreign, stratospheric, shipping, natural etc.). Recently published results for North America and Europe and additional results for India and the Arctic will be presented, with a particular focus on forest fires. The approach that allows us to calculate these contributions and explain the ozone changes, i.e., a novel ozone tagging technique introduced within a global atmospheric chemistry transport model CAM-Chem, will be discussed before we discuss the results.

At the end of the talk, you will be able to better appreciate: the pressing issue of controlling hemispheric pollutants which has become challenging in a tough geopolitical environment; the technical tools needed to produce confident estimates of source contributions and their strengths and weaknesses; the changes that have occurred in major northern hemispheric regions (US, Europe, India, Arctic) in terms of surface ozone pollution over the past two decades (2000-2018); and their attributions to different emission sources. Hopefully, this knowledge will provide a clear picture of what is needed to drive international policy for hemispheric pollution abatement.