Current Position

I am the scientific project coordinator of the German research initiative "Wolken und Niederschlagprozesse im Klimasystem" HD(CP)2.  This is a BMBF-funded 3-to-6-year project that is distributed over 18 institutes across Germany and involves currently more than 120 scientists. The main focus is to use high resolution modelling and observations to improve our understanding of how clouds and precipitation influence climate predictability.



Other activities 


Before this position, I have been working for two years as chapter scientist for the fifth assessment report of the IPCC 5th, specifically for the chapter on climate model evaluation. I have coordinated and helped the international effort for the chapter on climate model evaluation in working group I, together with the coordinating lead authors Jochem Marotzke and Greg Flato.



I am strongly interested in the political frame work of climate change science and policy. Some of my current and recent activities are:


  • I am chair of the conference and adviser of rimini-protokoll in the preparation of the (simulated) UNFCCC conference of the parties for the Hamburg theatre Schauspielhaus
  • Together with Sebastian Sonntag and Vera Schemann I am currently leading the Young Earth System Science community to strengthen the network of Young Earth System scientists from different graduate schools and institutions around the world. YESS was founded by Sebastian and myself in October 2010. We are currently negotiating with WCRP and WWRP to make YESS the world's primary Earth system science community. 
  • I have been conference chair and coordinator of the Interdisciplinary Conference of Young Earth System Scientists 2013, see for more details.
  • I am member of the scientific advisory board for the webpage
  • I am contributing author of the IPCC AR5.
  • I was part of the scientific advisory team to translate the IPCC 2007 FAQs into German (Link).