PhD project
Title: The quasi-biennial oscillation in a warming climate
Supervision: Marco Giorgetta, Ulrike Niemeier, Bjorn Stevens

In my PhD project I investigate how and why the quasi-biennial oscillation (QBO) of the zonal wind in the tropical stratosphere may change in a warming climate. To tackle this question I use high resolution simulations with the global circulation model ICON, which explicitly resolve convection as well as gravity waves. This enables a direct simulation of the QBO without the need for relevant parametrizations, which are needed in coarser resolution models and which are accompanied by overwhelming uncertainties, preventing a conclusive answer about the QBO characteristics in a warming climate so far.

Further interests
1) Dynamics of the QBO and its response to external forcings (e.g. volcanic eruptions or geoengineering)
2) General circulation in the stratosphere and its response to external forcings (e.g. volcanic eruptions or geoengineering)
3) Dynamic coupling between the stratosphere and the troposphere
 

M.Sc. Meteorology, University of Hamburg (2017 - 2020)
Master's Thesis: Stratospheric Injection of Sulfur - Injection of H₂SO₄ Compared to Injection of SO₂
Stay abroad: The University Centre in Svalbard (Longyearbyen, Norway), 2018

B.Sc. Meteorology, University of Hamburg (2014 - 2018)
Bachelor's Thesis: Cloud Correlations in Tropical Convection
Stay abroad: University of Oklahoma (Norman, USA), 2016
 

I. Quaglia, C. Timmreck, U. Niemeier, D. Visioni, G. Pitari, C. Brühl, S. Dhomse, H. Franke, A. Laakso, G. Mann, E. Rozanov, T. Sukhodolov: Interactive Stratospheric Aerosol models' response to different amounts and altitudes of SO₂ injections during the 1991 Pinatubo eruption, Atmos. Chem. Phys., https://doi.org/10.5194/acp-23-921-2023, 2023.

M. A. Giorgetta, W. Sawyer, X. Lapillonne, P. Adamidis, D. Alexeev, V. Clément, R. Dietlicher, J. F. Engels, M. Esch, H. Franke, C. Frauen, W. M. Hannah, B. R. Hillman, L. Kornblueh, P. Marti, M. R. Norman, R. Pincus, S. Rast, D. Reinert, R. Schnur, U. Schulzweida, and B. Stevens: The ICON-A model for direct QBO simulations on GPUs (version icon-cscs:baf28a514), Geoscientific Model Development, https://doi.org/10.5194/gmd-15-6985-2022, 2022.

D. K. Weisenstein, D. Visioni, H. Franke, U. Niemeier, S. Vattioni, G. Chiodo, T. Peter, and D. W. Keith: A Model Intercomparison of Stratospheric Solar Geoengineering by Accumulation-Mode Sulfate Aerosols, Atmos. Chem. Phys., https://doi.org/10.5194/acp-22-2955-2022, 2022.

H. Franke, U. Niemeier, D. Visioni: Differences in the quasi-biennial oscillation response to stratospheric aerosol modification depending on injection strategy and species, Atmos. Chem. Phys., https://doi.org/10.5194/acp-21-8615-2021, 2021.

Participitation in research cruise SO284
Details: R/V Sonne, 2021/06/27 - 2021/08/17, Emden - Tropical Atlantic - Emden
Duties: Launching of radiosondes in the Intertropical Convergence Zone (ITCZ)