Mourning for Erich Roeckner

Erich was a great role model for me. It was impressive how calmly he analyzed scientific and modeling problems and tested his ideas for solving them. He was also very open to involving others in his projects, such as myself and other young people, from whom we learned a great deal. The biggest and more or less never-ending project was, of course, the development of the ECHAM model and the MPI climate model, which later became the MPI Earth System Model. I still remember well how he led this difficult work in his calm and level-headed manner, even in times when rapid progress must have been very urgent. I certainly owe him a lot. Thank you Erich!

I learned so much from Erich Roeckner, not only about climate modeling, but also about being a thorough and detail oriented researcher. His kindness and patience provided impactful learning opportunities for younger researchers. My condolences!

Knowing him from the early days of my education at Hamburg University (Oceanography and Meteorology) and over the following decades of cooperation with the MPI-Met I was always aware of his his extraordinary input to the excellence in modelling development. He is really worth to be remembered as one the greatest "hidden" gems in modelling science. And I remember his very kind personality.

Mit großer Trauer habe ich erfahren, dass Erich vor einer Woche gestorben ist. Er war mein Mentor durch all die Jahre, die ich am MPI verbrachte. Ich habe von seinem profunden Wissen profitiert und er räumte mir die Freiheit ein, meine Interessen zu entwickeln. Er war nicht nur einer der besten Wissenschaftler, mit denen ich zusammenarbeiten durfte, er war auch einer der bescheidensten.
Ich denke an ihn in tiefer Dankbarkeit.

Erich war fast 20 Jahre lang mein Chef. Ich habe sehr gerne mit ihm gearbeitet, er strahlte immer so eine Ruhe aus. Sein Spruch war immer:
„Schnell ist langsam“ Uns so ist es auch heute, mal schnell etwas programmieren geht nicht.
Neben der Wissenschaft interessierte sich Erich auch für Literatur und Musik.
Erich war großer Wagner Fan, was dann auch irgend wann mein Interesse weckte.
Als ich die Begeisterung nicht mit ihm teilen konnte meinte er nur:
„Für Wagner muss man ein gewisses Alter haben“
Da ich jetzt auch ein gewisses Alter erreicht habe, werde ich es noch mal mit Wagner versuchen und dann werde ich sehr gerne an Erich zurück denken.

Dear Erich, thank you. Thank you for sharing your knowledge on climate modelling and for kindly giving your support when most needed. You remain in my memory. The 1990s, those exciting early years at MPI, and later in the 2000s, when you visited Bologna. Many years, many discussions. With my best sincere admiration and fondness, Elisa Manzini.

I am sorry to hear that Erich passed away. My thoughts are with his family!

I remember Erich as a devoted scientist with an aspiration to do excellent work that make an impact for a long time. Over time, many of us have benefitted from this when using the ECHAM climate model that Erich has been so essential for. Myself, I have used and worked with several generations of the model, such as the high-resolution version of ECHAM4 that has been essential for the scientific work I am most contended with.

I enjoyed my collaboration with Erich through the years, as a PhD student (with Erich on my defence committee), as a young scientist when using the ECHAM model for some “serious” modelling work and as an openminded, respectful and friendly project partner in probably one of the smallest EU-projects ever. And I am certainly grateful for honoured for the “Du” that Erich offered me in the early stage of our collaboration.

Erich was a pioneer in studying cloud effects on climate, first at the University of Hamburg and later at the MPI. One of his first papers was on the optical depth feedback (from clouds gaining more condensate mass with warming), showing how in the early days models were used to test theory. Later he was a pioneer in global studies of aerosol cloud interactions, together with Ulrike Lohmann who he mentored. They both provided my introduction to the institute. 

I think of Erich as one of the greats in what I would call the second generation of climate modelling, after Manabe and Hansen and those of that generation. As Hans von Storch points out, Erich was responsible for the development of many generations of MPIM's climate models. He should be credited for making some of the first truly compelling coupled models, and for understanding the role of physical processes, particularly clouds and aerosol, in making such models work. He deserves a great deal of the credit for the institute’s international acclaim as a modeling center, through his contributions to ECHAM and later the MP-ESM. Even today, when our focus is on ICON, we should remember that it was Erich who first suggested this direction, though he was loathe to take any credit.

Some of you may have heard me talk about the Gates number, i.e., the ratio between accomplishment and recognition. Erich had, in common with Larry Gates for whom the number is named, an astronomical Gates number. His modest, yet wise, manner left its mark on all those who made the effort to get to know him.. even a little bit. I like to think this mark remains part of our institute’s culture.

Erich Roeckner was one of the last major contributors of the Hasselmann/Bengtsson era at the Max Planck Institute for Meteorology. He was rarely the spotlight, but he was someone without whom the success and worldwide recognition of the Institute would hardly have been conceivable. The same is true of Ernst Maier-Reimer, who passed away in 2013.
What they shared was that both created essential tools without which many of the important and foundational research efforts at the Institute—especially its contributions to the IPCC—would scarcely have been possible. In Erich’s case, this was primarily the atmospheric circulation model ECHAM; in Ernst’s case, the ocean model LSG.
I have discussed the careers and perspectives on the development of scientific knowledge with many impressive colleagues in interviews. Unfortunately, that did not happen with Erich and Ernst. That is a great pity, because both had important things to say—especially since they were rather quiet personalities.
I entered climate research in 1976 as a doctoral student at the Meteorological Institute in Günter Fischer’s research group. It was Erich Roeckner who assigned me my dissertation topic and then let me set sail. Before long, our research interests diverged, and after I completed my dissertation, our contact gradually became less frequent, not only for that reason. I regret that, because Erich was an impressive person with whom I shared, for many years, ownership of a chainsaw as well as two white publications from the early 1980s. He also accompanied me on my first-ever flight (to Heathrow) and helped us through a tense moment when the bus driver asked us for “two pounds eich” for the ticket—something Erich correctly interpreted as “two pounds each.”

Es ist eine sehr traurige Nachricht, dass Erich gestorben ist. Seine Leistung in der Klimaforschung war wirklich außergewöhnlich. Über Jahrzehnte konnte man, wenn man nicht mehr weiterwusste mit dem Klimamodell, zu Erich gehen. Er kannte alle Details und hatte sich, so schien es, mit jedem Problem schon auseinandergesetzt.

Liebe Kollegen, liebe Familie Roeckner,

mit grosser Bestürzung hat mich heute die Nachricht von Erichs Ableben erreicht. Ich hatte das Glück, Erich als meinen Ko-Betreuer für meine Doktorarbeit am MPI für Meterologie in den Jahren 2007-2010 haben zu dürfen. Als Quereinsteiger in das Feld hat er mir stets mit Rat zur Seite gestanden und mich unterstützt, das ECHAM Atmosphärenmodell in unbekannte Klimazustände zu treiben.

Mit seiner hohen Fachkenntnis, ruhigen Art und beständigen Bereitschaft zur Hilfe war er eine Institution am MPI.

Ich wünsche Dir, Erich, alles Gute, wo auch immer Du nun weilen magst.

Aiko Voigt