CliSAP successfully finished in 2018. Climate research continues in the Cluster of Excellence "CLICCS".

### Zu Gast bei CliSAP: Anna Barry

09.07.2014

Anna Barry ist Mathematikerin und lebt in den USA. In den letzten vier Wochen war sie zu Gast bei Prof. Gualtiero Badin, der zu geophysikalischer Strömungsdynamik forscht. Mit ihm zusammen konnte sie Gleichgewichte in Verwirbelungen untersuchen und ihre Stabilität mathematisch beschreiben.

Das Interview wurde auf Englisch geführt.

CliSAP: Beeing a mathematician, what  fascinates you in climate research?

Barry: I was introduced to climate science while I was a Ph.D student. I took part in a "mathematics of climate" workshop that was the combined effort of the Mathematics and Climate Research Network (MCRN) and NCAR - the National Center of Atmospheric Research. This workshop sparked in me the drive to make some positive contribution to the greater knowledge. At first, I hoped this contribution would be to the world of climate science and later realized the importance of climate science informing mathematics. I started studying and analyzing conceptual climate models and have been amazed at the wealth of mathematics lurking within!

CliSAP: You stayed at the Cluster of Excellence for the past four weeks. What research did you do?

Barry: Fluids models are typically partial differential equations which are incredibly difficult to analyze. In certain situations, one can reduce the complexity of the model by focusing on specific features. In my work with Gualtiero, we consider vortex-dominated flows and use ordinary differential equations that describe the motion of the centers of the interacting vortices. Certain vortex configurations are equilibria, meaning that they stay in these configurations for all time when viewed from an appropriate frame of reference. Many stable equilibrium patterns have been observed in nature -  for a beautiful example, google "Mesovortices in Hurricane Isabel". Gualtiero and I have identified a number of physical examples of these equilibria, and have been able to analyze their existence and stability mathematically.

CliSAP: What would you say in wich ways you could add your expertise to the Cluster of Excellence?

Barry: I think my theoretical mathematics background can bring a different perspective to problems in climate. As I mentioned, there is new mathematics lurking everywhere! Working with Gualtiero and meeting other scientists in applied fields has reinvigorated my research. I've come away with new ideas for problems and collaborations. It was thrilling to be a part of the bridge connecting theory and applications and to be reminded that there are actual physical examples that match with mathematical theory. Beeing at CliSAP was a fantastic opportunity!

CliSAP: For the future, will something develop from your trip to Hamburg?

Barry: I hope to remain connected to the University of Hamburg. I will continue to work with Gualtiero and hopefully he will come to visit me in the coming year. In addition, I hope at least one additional collaboration on nonsmooth climate models will come out of this visit.