Charlotte Breitkreuz

My PhD project evolves around the development and application of data assimilation (DA) methods for paleo-ocean modelling. Data assimilation methods are not yet well-established in paleo-ocean modelling and the development of such methods raises many questions and challenges. The method I am developing is based on a Particle Filter approach. I spent a two-months research stay at the University of Reading in the department of Meteorology to work with Professor Peter Jan van Leeuwen who is an expert in the field of data assimilation and in particular in using Particle Filter methods.

I first met Peter Jan during a workshop in Leiden, the Netherlands, where I focused on understanding different DA methods and which, in the end, lead to my decision of using a Particle method in my project. Later, during EGU in April 2017, I met Peter Jan again and asked him for a collaboration for the development of a Particle Method for the specific application in paleo-ocean modelling. After discussing some details we decided that I will come to visit the University of Reading for 2 months to work on this project.

The University of Reading has a lively community in the field of Meteorology and Maths and has a big group of scientists working on data assimilation (DARC – Data Assimilation Research Centre). Upon my arrival at the university Peter Jan welcomed me to the DA group and to one of his PhD students who showed me around campus. During my stay I was based in the Mathematics department in a PhD office were I met many other PhD students and was welcomed into a lively environment with weekly coffee & cake meetings and the obligatory visit of the pub on campus every Friday after work. I particularly enjoyed to be based in the Maths department as Mathematics is my original background. Each week there were many seminars in the Maths and in the Meteorology departments evolving around topics such as climate modelling or in particular about DA. Especially, the DA seminars were of great interest to me as DA is my biggest personal research interest. There is no big DA community in Bremen and the research stay was a great opportunity for me to meet other scientists working with DA and to extend my network in the field of DA.

In the beginning of my stay I gave a short introductory talk in the DA seminar to introduce myself to the group. Later towards the end of my stay I presented my work in a regular long seminar talk which was followed by a lively discussion. Additionally, I participated in the bi-weekly Maths PhD seminar series. The seminar series is organized by PhD students and gives the opportunity to present your work in a casual environment. It was great for me to see other fields of application of Mathematics and I contributed a talk about using DA for paleo-ocean modelling. It was very interesting and a good exercise to prepare this talk for an audience of Mathematicians who are not familiar with climate or ocean sciences.

The two months in a new environment made in possible for me to focus only on the development of the method and not think about other aspects of my PhD. I had weekly meetings with Peter Jan during which we always had in-depth discussions. I highly profited from the expertise of Peter Jan and the discussions with him such that in the two months I made great progress in a comparatively short period of time. At the end of my stay the backbone of the method was developed and I performed the first successful experiments. I will continue developing the method at MARUM and stay in contact with Peter Jan via mail.

Besides from work, a research stay gives the great opportunity to discover the surroundings on the weekends. Even though Reading itself is not the most lively and interesting town, its surroundings offer many opportunities for weekend trips. Most prominent of course is London, which is only a 30-minute train ride away. I also spend one weekend in Devon which is in the South-East of England and has a lovely countryside, including two coast lines (one in the North-West and one in the South) and two national parks.

At the end of my stay I already felt at home in Reading and especially in the department of Mathematics. The two months were definitely too short in terms of work but also personally and I am looking forward to visiting the friends I made during that time. I will continue the development of the method at home and possibly go back to the University of Reading next year to further work with Peter Jan.

I am very grateful  to GLOMAR for providing funds for my research stay and making it possible. The research stay was a unique experience not only related to my PhD project but also for me personally.