Colloquium
Welcome to our colloquium.
Every semester we have fantastic new science on the physics of our environment presented by national and international guests and including our institutes achievements by talks from doctoral students and postdocs. We are looking forward to meet you at the IUP 1. Floor Seminar Room 108/110. Every Thursday at 11:15 during the Semester. Find the list of speakers below.
Colloquium
Table filters
Table
17.04.2025 | Dr. Minghui Zhang MPI- Mainz | Physics and chemistry of aerosols and clouds | ||
08.05.2025 | Dr. Elena Serra University Bern | Late Pleistocene paleoglacier and paleoclimate reconstructions in the western European Alps | Glacier fluctuations, sensitive to temperature and precipitation, serve as key proxies for reconstructing past climates. I present a detailed reconstruction of the Late Pleistocene glacial history of the Dora Baltea catchment in the western European Alps, using 10Be surface-exposure and luminescence dating alongside glacier modeling. Our findings highlight the timing and extent of ice advances and demonstrate how local factors like catchment size and hypsometry modulate glacier response to climate forcing. | 
|
15.05.2025 | Dr. Christopher Kyba | Visible band observations at night: the European Urban Light Explorer mission proposal | Thanks to advances in imaging technology, extremely high-sensitivity observation of Earth at night in the visible and NIR bands is now feasible. The regular acquisition of such data would fill in a major gap in Europe's Earth Observation program, and would open up new frontiers in remote sensing of the atmosphere, Earth's surface properties, and human development and activity. This talk presents the European Urban Light .Explorer (EULE) mission concept, and invites the audience to consider what future nighttime data acquisition might mean for their own research fields. | 
|
22.05.2025 | Prof. Dr. Kerstin Schepanski | The atmospheric dust cycle: Perspectives from satellite observations, field experiments and model simulations | Mineral dust aerosol is a major contributor to the atmospheric aerosol burden. Knowledge on dust sources and emission processes as well as the aerosols' journey through the atmosphere from source to sink is crucial for understanding various aerosol-atmosphere interactions including these on the Earth's radiation budget, cloud and precipitation formation processes. The presentation will discuss results from research that makes complementary use of satellite data, measurements, and numerical modelling in order to improve our understanding of the role of mineral dust in the Earth system. | 
|
05.06.2025 | Dr. Hyacinth Nnamchi GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany | Aerosols more important for Sahel climate change than greenhouse gases | The Sahel, the semi-arid region of Africa between the Sahara Desert and the rainforest, has experienced dramatic shifts from severe droughts in the late 20th century to wetter conditions in recent decades. However, the primary cause of these changes, especially the relative roles of anthropogenic greenhouse gases (GHGs) and aerosols, remains contested. In particular, the recent Sahel recovery tend to be generally attributed to rising GHGs. Using ensembles of state-of-the-art climate models, I will show that these changes were primarily caused by anthropogenic aerosols. Aerosol-induced slowdown of the Hadley Circulation, the overturning circulation of the atmosphere that drives deep convection just north of the equator, caused the prolonged droughts. The subsequent decline in aerosol emissions triggered a reversal to a wetting phase. In contrast, the contribution of GHGs is minimal, 3–7 times less than that of aerosols. I will argue that the strong sensitivity of Sahel rainfall to anthropogenic aerosols implies (1) a more profound impact on future climates than previously recognized and (2) that this reduces confidence in climate model projections and climate risk assessment, which continue to focus primarily on GHGs. | 
|
12.06.2025 | Dr. Felix Pithan | How do clouds and turbulence control polar climates? | Global climate change is amplified in the Arctic, which is warming at 3-4 times the global mean rate, and where wintertime precipitation is projected to double within this century. This Arctic amplification of climate change is caused by positive feedback processes such as the surface albedo feedback and the lapse-rate feedback caused by a bottom-heavy warming profile in an often stably stratified lower troposphere. These feedbacks depend on small-scale processes in clouds and boundary layers, which are still poorly understood and represented in models. In this talk, I will show how an air-mass following perspective in observations, modelling and conceptional understanding helps us to constrain crucial processes and to better understand how the Arctic couples to global climate. | 
|
26.06.2025 | Dr. Dietmar Öttl | Theoretical background and practical aspects of the Air Quality Modelling System GRAMM-SCI and GRAL | The air quality modelling system GRAMM-SCI/GRAL has been under continuous development for approximately 30 years as part of various national and international research projects. GRAMM-SCI is a non-hydrostatic, prognostic wind-field model based on the Reynolds-Averaged Navier-Stokes (RANS) equations, while GRAL is a Lagrangian particle dispersion model that includes a built-in CFD module for simulating microscale flow and pollutant dispersion around buildings and vegetation. This presentation highlights several innovative features and developments within both models—many of which remain unique or were first introduced in this class of models. Notable topics include GRAMM-SCI’s specialized discretization approach, as well as GRAL’s advancements in handling low-wind speed conditions, odour dispersion, and emissions from tunnel portals. | 
|
03.07.2025 | Prof. Dr. Mary Kang | Methane emissions from abandoned oil and gas wells and natural gas end use | Methane is a potent greenhouse gas, and reducing methane emissions is a fast and cost-effective way to slow global warming in the near term. In this presentation, I will focus on two methane sources for which national inventory estimates remain highly uncertain: abandoned oil and gas wells and natural gas end use. I will present an overview of available methane emission measurements for these two sources, including the different methodologies employed. I will also provide estimates of methane emissions of abandoned oil and gas wells and natural gas end use for Canada and the U.S., including a discussion of data sources and limitations. I will end with the implications of these results on mitigation potential and policies in Canada, the U.S., and around the world. | 
|
10.07.2025 | Dr. John Rapaglia | Strange Waves in Beautiful Places: Forced Non-linear Waves in Coastal Environments
| Along many coastlines, long-term morphological change is driven by common wind waves, however drastic short-term morphological change is often induced from more powerful non-linear waves such as Tsunami. In shallow coastal environments, the impact of Bernoulli waves from large ships in Venice, Italy, and storm-driven edge waves/Meteotsunami in Dingle, Ireland on coastal processes were investigated. 100s of ship wakes were analyzed and determined to be the driving force of dozens of meters of shoreline retreat along the main industrial canal in Venice Lagoon, meanwhile a special resonance wave forced by a massive North Atlantic storm created a non-linear oscillating wave with a period of up to 9 minutes, caused significant damage in Dingle, Harbor. | 
|
17.07.2025 | Dr. Nils Schorndorf | |||
24.07.2024 | Dennis Hofmann | New insights from Aeolotron experiments - Imaging and characterization of turbulent structures driving gas exchange at the air-water interface |