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26th February, 2024 14:00 CET


Two air quality experiments with PALM-4U: Lessons learned?


Dr. Christopher C. Holst

Research Group Leader: Urban- and Eco-Climatology
KIT-Campus Alpin/IMK-IFU
Karlsruher Institut für Technologie (KIT)


Online Seminar via Zoom
Link and password upon request
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More than half of all living humans resided in urban areas in 2022, leading to a concentration of
70% of primary energy consumption on only 1% of the planetary surface. Studying this small but
important part of earth in detail has been a challenge for biometeorologists, due to the large
spread of scales between the globe and a human. The past decade saw the proliferation of
compute resources and development of coupled urban microclimate models, such as PALM-4U,
which serve as a magnifying glass to study meteorological processes down to human scales. In this
presentation I will showcase and discuss two numerical experiments, to demonstrate the new
challenges arising from the availability of this new modeling tool. The first discussion revolves
around simulating ozone in an example urban space in Berlin, and how a simple experiment can
point out limitations of current observational capabilities and larger scale air quality modelling
products. In the second part, I will demonstrate the role of meteorological conditions and emission
data on particulate matter for a complex showcase simulation in Stuttgart. The last part of the
presentation will be a slightly philosophical conclusion on how these Findings relate to what is
often called ground truth.