Dr. Christoph Knote is an assistant professor at the Ludwig-Maximilians Universitaet in Munich, Germany. Christoph had been a postdoc in ACOM and returned for a one-month visit in July/August 2015. During his visit Christoph worked on advancing his chemistry box model BOXMOX by including the Master Chemical Mechanism (MCM) and providing means to drive the model with aircraft measurements like the ones taken by TOGA on the NCAR C130. For this he was primarily working with Geoff Tyndall, John Orlando, Christine Wiedinmyer, Louisa Emmons and Rebecca Hornbrook. He further helped including an updated treatment of secondary organic aerosol (SOA) into CESM together with Alma Hodzic, Simone Tilmes and Louisa Emmons. Finally Christoph started working on a chemical data assimilation toy model based on BOXMOX together with Jerome Barre.