Dr Annelize van Niekerk
Annelize works on the representation of orography in the Met Office Unified Model.
Areas of expertise
- Orographic flows
- Momentum and drag
- Gravity waves
- Numerical Modelling
- Parametrization
- Model evaluation
Current activities
Annelize is a visiting scientist working on orographic drag processes and their impacts on the large scale circulation within models. Her focus is on constraining orographic drag for parametrization validation and improvement of the Met Office Unified Model. She is also interested in the drag produced by non-orographic gravity waves and their representation within models.
It is difficult to measure the drag from complex orography directly (or even indirectly). As a result, Annelize is currently working on utilising high resolution limited area models over complex mountain ranges, such as the Himalayas, as a proxy for observed orographic drag. This work will help gain insight into missing processes in the model as well as identifying deficiencies in the current orographic drag parametrization scheme.
She has also been working with Perturbed Parameter Ensembles (PPEs) in collaboration with the Quantifying Uncertainty in Model Projections (QUMP) team. The aim of this work is to use PPEs and powerful statistical techniques to narrow the uncertainty in orographic drag parametrization (and other drag parametrizations) and to identify underlying issues with their formulation.
External collaboration activities also include: particicaption in the International Space Science Institute (ISSI) Bern team project: New Quantitative Constraints on Orographic Gravity Wave Stress and Drag; and leading a new Global Atmospheric Systems Studies (GASS) project on orographic drag and momentum transport.
Career background
Annelize joined the Met Office in May 2017, after completing her PhD in Meteorology at Reading University where she worked on the representation of orographic drag in models. Prior to this, she completed her undergraduate in Mathematics and Philosophy at the University of Liverpool in 2010 and went on to gain her masters in Astrophysics at Queen Mary, University of London in 2012.
External recognition
Annelize was awarded the Royal Meteorological Society's L F Richardson Prize in 2018.