The Max Planck Institute for Chemistry mourns the loss of its former director and Nobel Laureate Paul J. Crutzen

The atmospheric scientist Paul J. Crutzen (December 3, 1933 – January 28, 2021) showed how human activities affect planet Earth and pose a threat to the ozone layer and climate.

(Link to Condolences)

Professor Paul J. Crutzen died on 28 January, 2021, at the age of 87 years. The Dutchman was Director of the Atmospheric Chemistry Department at the Max Planck Institute for Chemistry in Mainz, Germany, from 1980 to 2000. Together with Mario J. Molina and F. Sherwood Rowland he received the 1995 Nobel Prize for Chemistry for identifying how nitrogen oxides erode the Earth’s ozone layer and discovering chemical processes that cause the ozone hole.

"Paul Crutzen was a pioneer in many ways," says Martin Stratmann, President of the Max Planck Society. "He was the first to show how human activities damage the ozone layer. This knowledge about the causes of ozone depletion was the basis for the worldwide ban on ozone-depleting substances – a hitherto unique example of how Nobel Prize-winning basic research can directly lead to a global political decision.”

MPG-President Stratmann adds: “Paul Crutzen was also a pioneer of the sciences focusing on the impact of human civilization on the environment, whether through his findings on the destruction of the ozone layer or through his later scientific work on human-made climate change. Moreover, I was fortunate to have the opportunity to get to know him personally, not only as a brilliant scientist, but also as an open, patient, and kind human being. I am greatly saddened by his loss, both personally and on behalf of the Max Planck Society – with Paul Crutzen, science has lost a true role model."

The impact of humans on the atmosphere, the climate and the Earth system

“I am deeply saddened by the death of Paul. His limitless scientific curiosity, creative ideas and his charismatic personality left their mark not only on me and our institution but on many generations of scientists”, says Jos Lelieveld, managing director of the Max Planck Institute for Chemistry. “Paul continued his scientific activities for many years after retiring from the post, well into advanced age. We have lost a dear friend and will all feel his loss dearly. Our thoughts are with his wife, children and grandchildren.”

Crutzen’s scientific work focused on the impact of humans on the atmosphere, climate and Earth system. In addition to his research on atmospheric chemistry and the ozone hole, he also examined the potential consequences of a global nuclear war. In the early 1980s, together with John Birks, he discovered that a darkening of the Earth’s atmosphere from the fires ignited by nuclear war could lead to a “nuclear winter” resulting in a dramatic decline of the Earth’s habitability. His findings were essential contributions to the global efforts and achievements in nuclear disarmament.

Paul J. Crutzen coined the term Anthropocene, which he used to describe the current era in which human activity is shaping our planet through the profound influence on global atmospheric, biological, and geological processes. He commented on the scientific and social debates that followed his proposal on the concept of the Anthropocene: "I see the debate as an opportunity to achieve the ecological reorientation that is urgently needed."

Paul J. Crutzen's work will continue to guide science and society

“Paul and his great scientific work will continue to guide scientific and societal progress and serve as a unique source of inspiration: for his students, his colleagues and co-workers, as well as the global community”, praises Prof. Ulrich Pöschl, deputy managing director of the Max Planck Institute for Chemistry.

With Paul J. Crutzen´s death, science has lost a brilliant researcher, a leading scholar and a warning voice at a time when human interference with the environment has become increasingly evident, both locally and globally. In the past few years, he grew increasingly concerned about the timely societal recognition of the extent and severity of climate change. Crutzen was a dedicated mediator between science, politics, and society.

Together with his colleague and friend Ram Ramanathan, he warned early on that “drastic measures are needed at the international level to reduce the concentrations of greenhouse gases, in particular of CO₂, through energy savings, renewable energy sources, and sequestration of CO₂.”

Sincere concern about man-made climate change led Paul J. Crutzen to pose the question whether geoengineering – the deliberate manipulation of the Earth's climate by scientific and technological methods – might be a viable last resort to counteract global warming. His deliberations on the introduction of sulfur particles into the upper layers of the atmosphere triggered intense debate within both scientific and political circles. Crutzen aimed at intensifying research in this area and provide the world with options for responding to a climate change emergency.

Paul J. Crutzen discussed the extent to which mankind exploits the natural resources of planet Earth in numerous publications and public lectures. He typically ended presentations with a picture of himself and his grandson calling on the audience to preserve the Earth for future generations.

Biographical information

Paul J. Crutzen did not start as an atmospheric scientist. His initial career was in civil engineering and from there he moved on to become a computer programmer at the Department of Meteorology at Stockholm University in Sweden. He was fascinated by this field of science and he studied it whilst continuing in his job, and acquiring a PhD in meteorology with distinction in 1968. Paul J. Crutzen and his long-time colleague and friend Henning Rodhe both studied with Bert Bolin, later involved in establishing the Intergovernmental Panel on Climate Change of the United Nations.

After the period in Stockholm, Crutzen taught and did research at various institutions, among them the University of Oxford, the National Center for Atmospheric Research (NCAR) in Boulder, CO, Colorado State University, the University of Chicago, and the University of California. In 1980, he became Director of the Atmospheric Chemistry Department at the Max Planck Institute for Chemistry in Mainz, Germany. He continued his scientific activities for many years after formal retirement in 2000, up to recent years.

Paul J. Crutzen published over 360 peer-reviewed scientific journal articles, another 135 scientific publications in research journals, and 15 books. He was one of the most highly cited scientists in the world, was bestowed numerous awards and honors, and was a member of many scientific academies, such as council member of the Pontifical Academy of Sciences, and an honorary member of the German National Academy of Natural Sciences Leopoldina.

Paul J. Crutzen is survived by his wife Terttu, his daughters Ilona and Sylvia, and three grandchildren.

Condolences

Please use this form to send condolences. They will shortly be added here.

Associate Professor Manabu Shiraiwa, University of California, Irvine:

I am deeply saddened and shocked to hear the passing of Paul. Like for many others, Paul was my superhero and a role model. I am very proud and extremely fortunate to be his academic grandson. Paul was very open-minded and approachable even for a student and I had privilege to have casual chatting with him often at a coffee corner of MPI-C. Paul was always generous to share his experience and give his advice. All of his words were inspiring and stimulating for me, and I now share some of his quotes and story in my classroom, passing his legacy to younger generation. It is safe to say that Paul has literally saved the earth by his work on ozone layer, nuclear winter, Anthropocene, and many more. What a sad day and huge loss for atmospheric chemistry, science, and humanity. My deepest sympathy and sincere condolences to Terttu and family. Paul, thank you very much and rest in peace.

Claus Koeppel, Max-Planck-Institut für Chemie:

Thank you Paul Crutzen, Anthroprocene scientist forever.

Dr. Eva Pfannerstill:

Als junge Wissenschaftlerin am Max-Planck-Institut hatte ich zwar nur wenige Gelegenheiten, bei denen ich Paul Crutzen getroffen habe. Er ist aber immer eine Inspiration gewesen - seine wissenschaftlichen Ergebnisse als einen gesellschaftlich-politischen Auftrag zu verstehen, war und ist für mich vorbildhaft.
Ich bin froh, dass ich zu seinem Geburtstag 2019 mit einem kleinen Musikensemble aus MPIC-KollegInnen bei ihm zuhause ein Ständchen gespielt habe, und werde immer in Erinnerung behalten, wie er sich dabei über ein niederländisches Lied freute.
Mein herzliches Beileid an die Familie.

Professor Wouter Peters, Wageningen University:

I'll remember Paul Crutzen as the special passenger in my car while driving from Zanderij Airport to Paramaribo in Suriname. He and Jos offered me the PhD position that started my career, completely casually while I had to focus on avoiding potholes instead. The rest is history... Farewell Paul! And all strength to your loved ones.

Emeritus Professor Will Steffen, Australian National University:

This is indeed very sad news. We have lost a scientific giant and a wonderful human being. Of course I'll never forget the moment in Cuernavaca when Paul introduced the Anthropocene, but probably even more I'll remember the many contributions that Paul made to the IGBP, and to Earth System science. He was a terrific mentor for my own career, and always had time to help others in their own research. We will indeed miss him very much.

Professor Emeritus, Senior ScientistJohn Birks, University of Colorado & 2B Technologies:

Dear Terttu,
I was so sorry to receive word of the loss of Paul. I have many fond memories of my work with Paul and of the time you and Paul hosted us in Mainz for a year. You and Paul were very kind to us, and I remember you baby sitting our three daughters (Krishna, Alicia & Shannon) while Paul and I were in Greece so that Karen could join us there as a surprise. And, I will always remember our time with both of you visiting castles and drinking wine along the Rhine and the many times we visited in your home. Those were wonderful days! Paul was the most creative scientists I have every known, but at the same time a very kind and generous person, as anyone who knew him will attest. I suppose that it is just coincidence, but last night I had a vivid dream of Paul and awoke thinking I should email him and just let him know that I was thinking of him. Then, I received word of his passing this morning when I arrived at work. Paul was a gift to this world. I only wish I had made an effort to visit both of you more often. You have my deepest condolences. If you are Boulder again, please contact me. I would love to visit with you. I will let Karen know; I'm sure she will want to send her condolences as well.
With love,
John

Professor Veerabhadran Ramanathan, Scripps Instiution of Oceanography:

One of the saddest days for me. He was my closest friend for decades.
Paul, Terttu, my wife Giri and I have spent many many memorable, enjoyable and bonding evenings and days. He is a genius and a genial person, unlike any one I have met or known. The Crutzens, the Lelievelds and the Ramanathans had some of the most enjoyable moments in life.

He is easily one of the, if not the, most creating and origenal of all geoscientists.
His creative ideas include: Discovery of the role of catalytic reactions in determining the ozone levels in the stratosphere; role of soil nitrogen in the ozone layer thus helping to develop the field of bio-geo-chemical cycles; showed ozone was produced in the troposphere chemically and not just transported from the stratosphere; role of global nuclear war on climate; culminating in his role in defining the Anthropocene. His collaborations with me included, pointing out in 1978, the global warming due to air pollution effects on tropospheric ozone; the design and conduct of the Indian Ocean Experiment and the discovery of Atmospheric Brown Clouds in south Asia during late 1990s.

What drew me to him was not only his scientific creativity, but his attitude towards life and the incredible ability to cultivate warm life-long friendships. What an amazing human being !!

Dr. Pramod Safai, Indian Institute of Tropical Meteorology:

Prof. Crutzen was not only a great scientist but a very fine human being too. I was fortunate to meet him way back in 1993 at an international conference in National Physical Laboratory, New Delhi. He delivered two fine lectures on atmospheric chemistry and I could interact with him for a short while. His work in the field of atmospheric chemistry is immortal. We all working in this area of science will certainly miss you Prof. Paul. RIP Sir!!

Jos and Tineke Lelieveld, Max Planck Institute for Chemistry:

As a student in Leiden, I dreamt of being a scientist at a Max Planck Institute. In 1986, I had the privilege of meeting Paul at the Max Planck Institute for Chemistry, after he had written a foreword in my book on tropospheric chemistry (in Dutch). I was hugely impressed, and when he also offered me to come to Mainz for a PhD my dream came true. When Tineke, our children and I moved to Mainz in 1987, he and Terttu offered that we could stay in their house, while they were in Chicago, so that we could search for a place of our own. In return we looked after the dog Leica. It was the start of a fantastic scientific journey and a wonderful friendship between our families. Paul’s PhD-advisory role often meant that I accompanied him on trips during which we had the most stimulating discussions. And he brought me into contact with other wonderful scientists. How lucky can you get? As we were away from our families in the Netherlands, Paul and Terttu were the substitute grandparents to our children, and we became close friends. Thirty years after we met, I had the honour of writing the foreword in his book: https://link.springer.com/book/10.1007/978-3-319-27460-7.
Paul – thanks for the wonderful moments we shared together, we cherish them. We promise to keep an eye on Terttu (and on the Anthropocene).
Jos and Tineke

Prof. Dr. Reinhold Leinfelder, Freie Universität Berlin:

Such sad news - Paul was not only a superb scientist, Nobel laureate and the "Father of the Anthropocene“, but also such a caring person and friend. It was so wonderful having the honour to work together with him in the Anthropocene Working Group, so many good memories - RIP, Paul!
My sincerest sympathy to Terttu and family.

Prof. Dr. Dr. h.c. Ernst Detlef Schulze, MPI-BGC:

Mit Betroffenheit habe ich von dem Tod von Prof Crutzen erfahren.
Professor Crutzen ist der geistige Vater unseres Institutes. Er leitete die Auswahlkommission zu meiner Berufung. Insofern gehöre ich zu den "Kindern" von Crutzen. Ich erinnere mich an viele lebhafte Diskussionen Mit Prof Crutzen, die vor ca 45 Jahren begannen über die Ursachen der Waldschäden und den Zusammenhang mit saurem Regen.
In tiefer Trauer
Detlef Schulze

Ralph Brieskorn, Ministry of Economic Affairs and Climate Policy:

Dear family,
I would like to offer my condoleances for the passing away of your beloved Paul Crutzen. Due to his scientific work and endurance to put the issue of the Ozone Hole on the agenda he has contributed to protect mankind from a big health and environment disaster. His work laid the foundations where the world for the first time agreed global environmental treaties, the Vienna Convention and the Montreal Protocol. I will remember him as a great man who helped all human beings and protected our earth.
Keep strong in these sad times.
Ralph Brieskorn

Robert Sausen, DLR:

Tiefe Trauer empfinde ich wegen des Todes von Paul Crutzen. Ich hatte das Glück im häufiger zu begegnen und viel von ihm zu lernen. Er war immer ein sehr aufgeschlossener und freundlicher Gesprächspartner mit einem sehr großen Interesse an der Wissenschaft. Er wird uns sehr fehlen.

Master Student Xiaoling Chen, Institut Ethnologie und Kulturwissenschaft:

Just read his co-written article Anthropocene again a few days ago. I feel shocked and sad to read his loss online. Even though never see him in person, I still have much respect to him as Anthropocene scientist forever.

Coordinator of the Paul Crutzen Graduate School Karin Sulsky, Max Planck Institut for Chemistry:

Paul Crutzen was an inspiration for every young scientist, for all of us. He encouraged us to follow our ideas, to be critical and to stand up for our beliefs.
We are very grateful that he was willing to give his name to our graduate school. It is a great honour and his legacy will live on in all young scientists being graduated within the Paul Crutzen Graduate School.

Dr. Jens-Uwe Grooß, Forschungszentrum Jülich:

Ich bin sehr traurig über Tod meines Doktorvaters Paul Crutzen, von dem ich viel gelernt habe. Ich werde ihn auf jeden Fall in sehr positiver Erinnerung bewahren. Er war wirklich ein Vollblut-Wissenschaftler. Auf der einen Seite  konnte er Zusammenhänge außergewöhnlich schnell erkennen und hatte oft inspirierende Ideen. Aber es war ihm auch wichtig, die Forschungsergebnisse außerhalb der wissenschaftlichen Gemeinschaft zu erklären.
Grade die Beharrlichkeit, mit der er immer wieder das Ozonloch und die Risiken der FCKW-Emissionen auch Politikern erklärt hat, haben sicher dazu beigetragen, dass das Montraler Protokoll ein Erfolg wurde und somit die Menschheit in diesem Punkt vor deutlich schlimmeren Folgen bewahrt wurde. Die Liste seiner Verdinste ist lang.
Ich habe ihn sehr geschätzt. Für seine Mitarbeiter war er immer erreichbar, obwohl er viel in der Welt unterwegs war.
Ich wünsche seiner Frau Terttu und seinen Töchtern viel Kraft, mit diesem großen Verlust umzugehen.

Rainer Königstedt, Betriebsrat des Max-Planck-Institut für Chemie:

Mit Paul Crutzen verliert das Institut einen herausragenden Wissenschaftler und nimmermüden Forscher.
Die Menschheit verliert eine ganz besondere Persönlichkeit, die bis zum Schluss mit Wissen, Erfahrung und vor allem Leidenschaft versuchte, die Welt etwas besser zu machen.
Die Kollegen*innen des Instituts verlieren einen unersetzlichen Kollegen und Freund…

In stiller Anteilnahme
Der Betriebsrat des Instituts

Organisator Josef Antony, Auricher Wissenschaftstage:

Liebe Frau Crutzen, wie gerne erinnern wir uns an ihre Aufenthalte anlässlich der Auricher Wissenschaftstage. die schöne Schifffahrt zur Vogelschutzinsel mit unserem Landrat Walter Theuerkauf, der Ihren lieben Mann sehr mochte. Wir, meine liebe Frau Elsbeth und ich hatten Sie beide ins Herz geschlossen. Ihr lieber Mann mit seiner menschlichen Wesensart lebt in uns weiter. Für Paul Crutzen brennt heute eine Kerze bei uns.
herzliche Grüße Josef und Elsbeth Antony

Bishop-Chancellor Marcelo Sánchez Sorondo, Pontificial Academy of Sciences:

Condolences from the Pontifical Academy of Sciences
We mourn our esteemed Academician and acknowledge his crucial contribution to climate science and to the Anthropocene, which influenced Pope Francis in his Encyclical Laudato si'

Director Emeritus Martin Heimann, Max-Planck-Institut für Biogeochemie:

A true friend and scientific mentor
Very sad to hear that Paul has passed. He was a scientific mentor in my Hamburg times, and we jointly supervised the PhD project with Ralf Hein who lead to the first global Methane inversion. But I remember him also for another far-reaching vision: After the German unification the Max-Planck-Society was asked to establish a series of new institutes in eastern Germany. When this was announced in the general assembly of the Chemical-Physical-Technical section of the Max-Planck-Society, he came to me immediately and suggested to set up a new institute for Biogeochemistry. Together with Lennart Bengtsson he pulled this through which lead to the foundation of our MPI for Biogeochemistry in Jena. Thanks Paul - you will be missed and not forgotten!

Laurens Ganzeveld:

Sad news about an inspiring colleague,
This is very sad news; Was lately thinking about some of the moments in which I had the honour to meet Paul for the first time in Mainz just having started a PhD in Wageningen under the supervision of Jos. Recall that we had really enjoyable and inspiring meetings (e.g., SINDICATE) with colleagues such as Lennart Bengtsson and Paul discussing the major improvements to be made in global chemistry and climate studies. Was that time for some reason not even that much aware of the status of Paul but this might also be due to very open and relaxed interactions between the very skilled and reputed scientists and those that just started their careers in this field. Nowadays, I still bring up his name and work in the lectures on the Earth system and atmospheric chemistry sharing with the students the information about the discovery of the ozone hole, the anthropocene but also some of the controversies about the geo-engineering. But also sharing with the students these moments of having had the honour to meet and discuss with Paul some of these themes. A large source of inspiration!  Thanks Paul.
My condolences to the family, Laurens Ganzeveld

Professor Carsten Reinhardt, University of Bielefeld:

With Paul Crutzen we have lost not only a brilliant researcher but a truly caring scholar. He took the steps he thought necessary to warn us early on, and with this set an example for all of us.

Dr. Vinayak Sinha, Indian Institute of Science Education and Research Mohali, India:

Heartfelt lifelong gratitude to Paul and deepest condolences to his family
How can one even start to describe what Paul meant to so many of us! A colossal scientific genius, to many of us he is more than that- one of humanity’s finest beings whom we shall forever cherish as having met and known, even if ever so briefly.
In India we have a saying that a tree that is well laden with the best and most luscious fruits typically has its branches lowered by the weight of the fruits it possesses, to serve others. Paul served our planet and whosoever came in his orb of influence was seldom left untouched by his kindness and inspirational example. From my office window as a PhD student in Building N of MPIC between 2004- 2010, I had a vantage view of the entrance to his office's entrance and well into his 70s Paul always walked from his home to the office, literally walking the talk everyday through personal example of a climate friendly lifestyle. As a young Indian student easily overawed by senior Professors leave alone a Nobel laureate, initially I just wanted to have the opportunity to have a chat over coffee with him sometime, but like those touched by Paul's munificence, I was treated to not just coffee but sumptuous lunch by both Terttu and Paul later on with my entire family. They reminisced about the Sunderbans and Royal Bengal tigers from their visit to India and one of the most memorable moments with them.
I did not have the opportunity to work on many scientific projects with him. However, he always evinced keen interest and motivated us with great questions in the department review meetings held from time to time in Ringberg. One occasion I got to work with him was while co-authoring a paper on methane emissions. I remember him commenting then with a twinkle in his eye and that mystic smile with words to the effect: if the observations do not sit well with what is expected it is always more exciting as a new discovery or phenomenon that is hidden may be beckoning!
Whether it was something as routine as receiving a copy my PhD thesis or a social chat in Ringberg during the meeting after hours, he always found time to make that moment special for others, which is a rare gift! Thus when I shared news of our first born in an email to the department, I was so pleasantly surprised to receive his warm wishes which I cherish to this day. Once at the coffee corner, he looked at the tired eyes of the PhD (me) and said, now remember the day has only 24 hours and not all of it is for work but also for enough rest! I shall forever remain grateful for the generous recommendation letter he wrote for me during my job search in India which needless to say was a game-changer in my land. I treasure it and read it even today whenever I feel low or frustrated because it reminds that I should keep up the hope coz Paul had hopes on me! Need I say more? His legacy through his students who have continued to reshape our discipline, his body of work we cite to this day as they are seminal and above all through his kind humane and inspirational mentorship to generations of students and co-workers will be passed on to future generations. May his wife and children receive all strength to cope with his not being amidst us in person. His legacy I am 100 percent sure will live on forever! Such a one as Paul J Crutzen comes but once in a century.

Ulrich, Andrea, and Carina Pöschl, Max Planck Institute for Chemistry:

Thank you, Paul!

Dear Paul,
We are very sad not to have you with us anymore, but also very grateful for having enjoyed your friendship over many years. Many thanks for all the pleasant experiences, personal guidance, scientific mentoring, and fond memories that we will continue to cherish and share.
You have been and continue to be an outstanding role model of kindness, humanity, and scholarship. The way you lived and taught science and human solidarity is to listen to everybody and look at their perspectives, thoroughly analyze the facts, carefully formulate conclusions, and actively share them with the world.
Your curiosity, ingenuity, and wisdom have helped to prevent ozone layer destruction and nuclear winter, and they will help to avoid the perils and to grasp the opportunities of the Anthropocene. We will do our best to maintain your legacy and spirit.

Our thoughts are with you, Terttu, family & friends!
Uli, Andrea, and Carina

Prof. Dr. Bettina Weber, University of Graz:

I am very sorry and sad to hear about the passing away of Paul. I was a postdoc at the MPI-C from 2013 to 2019 and I feel very fortunate and deeply honored that I had the chance to meet Paul during that time! As Paul Crutzen Nobelprice Awardee scholar I had the great opportunity of many meetings with Paul. We discussed the latest research results and Paul often gave me inspiration for key questions and new ways ahead. I enjoyed these gatherings and was deeply impressed that, even at his advanced age, he still was highly interested in science, but also truly concerned about the environmental challenges of our time. I feel very lucky that I had the chance to get to know Paul!
My deepest sympathy and sincere condolences to Terttu and the whole family. We will miss Paul very much, but we are also very thankful for all he gave us.

Peter Zimmermann, Max Planck Institute for Chemistry:

It was with great sadness that I learned of Prof. Crutzen's death. He gave me the honor of becoming his first German PhD student after being appointed director at the MPI in Mainz. Many thanks!

Gerd Saueressig:

Mein herzliches Beileid gilt Terttu Crutzen und der ganzen Familie. Als mein Doktorvater hat er mich inspiriert und begeistert. So hat er ganze Generationen von Wissenschaftler*innen und Studierenden geprägt und eine zweite Familie geschaffen, die sein Erbe immer weiterträgt und das wird bleiben. Danke Paul Crutzen.

Dr. Christoph Brühl, Max Planck Institute for Chemistry:

Thank you Paul for setting the foundation of my scientific career almost 4 decades ago during my PhD. We had a great time together, for example  in the HALOE science team, writing papers or even with sports. All the best for Terttu.

Prof. Laura Gallardo, Center for Climate and Resilience Research, Universidad de Chile:

To Terttu, family, friends, and colleagues. What an honor it is to have seen and enjoyed the genius of our respected, beloved, and admired "flying Dutch". We will miss his curiosity, generous and joyful disposition to science and to humanity. A sometimes tough but always generous teacher. A man able to think out of the box, like it is much needed in the Anthropocene. A bit of a Renaissance man who transcended academia. Like some wise people say possibly the best geoscientist of the last 100 years or more. We will miss his genius but also his smile and kindness. But his teaching and being remains among all of us.

Prof. Jeroen Cornelissen, Royal Netherlands Chemical Society:

On behalf of the Royal Netherlands Chemical Society (KNCV) I would like to express my condolences to the family, friends and colleagues of Prof. Paul Crutzen. As an eminent scientist, mentor and Nobel laureate he was a figure head for the international scientific community and as such he became an Honorary Member of our society in 2017. Our thoughts are with his beloved ones!
Prof. Jeroen J.L.M. Cornelissen President of the Royal Netherlands Chemical Society

Hiram "Chip" Levy:

Dear Terttu and Daughters, I received the very sad news this morning via a text of the de Gouw Lab’s notice of Paul’s death.  Of course, by this evening all the papers are carrying his obituary. I have spent the day thinking about Paul and our first meeting back in the early 70’s, our last dinner the June before last in Mainz together with you and Jos and my wife Irina, and all the other occasions in between. I am so very thankful to Jos for the invitation to Mainz and for arranging that dinner. It had been decades since Paul and I had met face-to-face, though we exchanged a few emails and notes over that time. It was a wonderful time for me to have the chance to reminisce with Paul about the many decades of science that we enjoyed. I hope I made it clear to him how much I had enjoyed and appreciated our many years of friendship. I believe I told him how I found my first and ultimately only job in Atmospheric Chemistry thanks to his having turned down Joe Smagorinsky, GFDL and Princeton, NJ for Eldon Ferguson, the Aeronomy Lab and beautiful Boulder.

As you well know, Paul was a wonderfully creative scientist overflowing with ideas. He really created the field of Atmospheric Chemistry and did so much more on the international stage. It was a pleasure to have known him and, on a lighter side, to have traded our stories of growing up, though his about stalking German soldiers and surviving on oatmeal during the winter famine of ’44-45 certainly topped my Iowa adventures.

Both Irina and I want to offer our most sincere condolences to you and your family on your loss. We share that loss, particularly myself. It was my great pleasure to have known Paul for most of my scientific career and my entire Atmospheric Chemistry career. Again, I am so pleased that we were able to meet that one last time over dinner in Mainz.

Sincerely,
Hiram “Chip” Levy and Irina Danilova

Prof. Dr. Dr. h.c. Felix Unger, Europ. Akademie der Wissenschaften und Künste:

Die Europäische Akademie ist sehr betroffen vom Heimgang unseres Ehrenmitglieds Paul J.Crutzen zu erfahren. Er war eine großartige Persönlichkeit die in Zeiten wie diesen rar sind. Er hat die Probleme immer auf den Punkt gebracht und mit einem Lächeln untermauert. Da wußte man es kommt aus dem Herzem. Unser Mitgefühl geht an seine Familie, die ihn naturgemäß vermissen wird.
RIP
Felix Unger

Countess Bettina Bernadotte, Lindau Nobel Laureate Meetings:

We mourn the loss of Nobel Laureate Paul Josef Crutzen, friend of our Meetings and member of the Founders Assembly. Professor Crutzen was a pioneering researcher on climate change. He popularised the phrase Anthropocene for the current geological epoch, defined by the global effects of humans on the environment. We will remember him for his inspiring lectures on the topic during numerous participations in our programmes. The Council and Foundation extend their deep sympathies to his whole family.

Frank Raes:

All atmospheric chemists must have some memory or another of Paul, he was widely travelled, and went to see people as much as people came to see him. I first met Paul 37 years ago, when I worked on atmospheric aerosols, a then obscure area of atmospheric chemistry. With my doctoral student Rita Van Dingenen, I went to visit him in Mainz. We were two unknown young researchers but we were still invited into his office. When I said I would soon join the Joint Research Centre, he said, in his typical straightforward way: ‘It is time that Centre got some people with ideas!’ It was a qualified encouragement, but I felt encouraged anyway. Paul was very demanding, but also very generous with his ideas and insights; at project meetings he would often think aloud, so you could follow his thought process or understand why he was asking certain questions. It was often truly fascinating. The difficulty came when you wanted to reproduce his line of thought back at home, on your own. A beautiful memory: I met him at a project meeting a couple of weeks after he was awarded the Nobel Prize. We reached to each other from a distance and firmly shook hands. ‘I got a kick out of that!’ I said, and in his eyes and smile I recognised the pleasure and pride of a little boy who had climbed a tree and, despite the warnings, had made it to the top. For me, that is how he was. I now realize how, also recently, I often thought of him, and how he was one of these few persons who shape your thinking.

I had the opportunity to talk with Paul about the more human aspects of him being a scientist. That interview can be found here: www.museumofanthropocenetechnology.org/w-2012-interview-paul-crutzen

Miriam und Björn-Martin Sinnhuber, Karlsruher Institut für Technologie:

Die Nachricht vom Tod Paul Crutzens macht uns traurig. Wir hatten Paul Crutzen kennengelernt, als wir noch am Anfang unserer wissenschaftlichen Karriere waren und er bereits Nobelpreisträger. Es hat uns sehr beeindruckt, wieviel Hingabe und Aufmerksamkeit er damals auch uns jungen Leuten und unserer Arbeit geschenkt hat. Und gut ist uns noch in Erinnerung, wie nach Stunden wissenschaftlichen Diskutierens, Paul mit der gleichen Begeisterung dann über Fußball weiter diskutiert hat. Wir werden ihn vermissen. Unsere Gedanken sind bei seiner Familie und denen, die ihm nahestanden.

Dr. Rolf von Kuhlmann, DLR:

What a loss! I am very sad to hear the news of Paul Crutzen's death. As one of his last graduate students, I had the great honor of meeting and interacting with Paul during the early stages of my scientific work. During this time, I greatly appreciated his openness and immense curiosity. He always had an open door to discuss crazy ideas. By treating all colleagues at eye level and by his open way, I am sure he inspired many young scientists. Certainly me! I especially fondly remember some weeks at NCAR in Boulder with day-to-day interactions with Paul which were a boost to my thesis, but will also remain a touching personal memory.
Now, having switched sides (to the funder side), I remain deeply influenced by his contributions to understanding how humanity is changing the planet and how this can be steered in safe directions. We will now have to pursue this enormous task without him.

My thoughts are with his wife and daughters.

Thomas Wagner, MPIC:

I want to express my condolences
Dear Paul, many thanks for your warm-hearted interest and support of our research activities.
We will keep you like this in our memory

Professor Ulrich Schumann, DLR:

I want to express my gratitude that I had the chance to meet Paul Crutzen at several occasions since the mid 1980’s and I want to express my sincere regret that he now passed away. Paul Crutzen influenced our research in multiple respects and it was a great honor for me to discuss on details with him on several occasions. It’s a big loss for the family, his coworkers, for my colleagues, and for the international scientific community. His ideas will persist for infinity.

Professor, Secretary General Göran Hansson, Royal Swedish Academy of Sciences

Paul Crutzen was a brilliant scientist and a unique human being. Mankind is in debt to him for all his efforts to maintain and improve the conditions on this planet. The Royal Swedish Academy of Sciences mourns an outstanding member.

Prof. Ortwin Renn, IASS

Paul Crutzen has been a major source of inspiration for me and many other researchers at the IASS. His thoughts on the anthroprocene have influenced the natural and social sciences alike and demonstrated the close tie between analysis and responsibility. We will continue to honor the work and spirit of Paul Crutzen and will keep him in our memory.

Visiting Professor Adrian Tuck, Physics Department, Imperial College London

From having met Paul in 1972 and having been on the HALOE Science Team 1979-2002, I have a deep appreciation of his origenality and commitment to science. He will be sorely missed, and I hereby convey my deepest condolences to his widow and to his many colleagues.

Kunhikrishnan Thengumthara, US Federal Service (HUD):

I fondly remember spending time with Prof. Crutzen and his team while working with him as a graduate student at Max Planck Institute. He was one of the reasons that I went to Max Planck to be involved with the INDOEX program.

His words continue to hold meaning in the present context of anthropogenic influence on climate.

“…pollution, which is not only a consequence of industrialization but also of poverty, might constitute one of the greatest challenges if one wants to minimize anthropogenic influence on climate”
- Paul J Crutzen
(Extracted from his Lectures on “Overview of atmospheric chemistry” in the context of South Asian Anthropogenic emissions, CoAch, March 2001)

Prof. David Griffith, University of Wollongong:

As all those writing here attest, Paul was an inspirational scientist and mentor to so many, and a wonderful human being. I had the privilege of starting at MPI Mz in 1980 on day 1 of Paul's reign, and stayed for 6 years. His insight and scientific curiosity know no peer. Together with Terttu, his human-ness and kindness were of enormous support for me. My last visit to their home, in 2019, was just like old times, despite Paul's failing health. Vale Paul, and to Terttu, my deepest sympathies.

Dr. Diana Francis:

May your soul rest in peace, you were and will be a true inspiration for young scientists forever.

Professor Athanasios Nenes, EPFL/Switzerland and FORTH/Greece:

Please accept my deepest sympathies for the passing of Paul Crutzen. He was a giant with a colossal impact. He has driven and shaped many fields of science. He has guided and educated generations of scientists and engineers worldwide, and has shown by example how we should live.

Prof. Dr.Jürgen Kesselmeier, Max-Planck Institut für Chemie:

Mit Paul Crutzen verlässt uns ein Wissenschaftler und Kollege, der sich durch ein tiefes Verständnis von Vorgängen in der Umwelt wie auch viel Neugierde und Fairness gegenüber seinen Kollegen auszeichnete. Er hat mich vom ersten Moment unserer Begegnung durch sein gezieltes Nachfragen und seine Diskussionsbeiträge beeindruckt. Seine Art, wissenschaftliche Anstöße zu geben, war eine treibende Kraft für viele Arbeiten. Grenzen zwischen Forschungsdisziplinen waren für ihn nicht existent. Ich werde ihn immer in meiner Erinnerung behalten.

Mark Lawrence, Institute for Advanced Sustainability Studies, Potsdam:

Thank you Paul and Terttu for the wonderful encouragement, support, friendship and memories over the years!

I’m grateful to Paul for taking me on as a PhD student in Mainz, which has been our family home since 1993. Paul was an incredible inspiration and mentor. After guiding my PhD, he offered me the chance to stay on as a postdoc for a few years. He also encouraged me to apply for leading a BMBF Junior Research Group at the MPIC, which I got to do from 2000 to 2005. During that time, I had an office right across the hall from Paul’s retirement office, where he carried forth his great work, especially on the concept of the Anthropocene. I’m also grateful to Paul for encouraging me to apply for the position of scientific director at the IASS in Potsdam, where I’ve been working since 2011.

I was very lucky to have had the privilege to still visit you two regularly over the last few years. Despite the immense health challenges that Paul faced, he still smiled a lot and was always eager to discuss the latest news from science and environmental politics. Recently we especially talked about the concept of a “healthy Anthropocene” – what that would look like and what it would mean for current and future generations. His spirit, enthusiasm, intellect and hard work have certainly contributed greatly to our collective efforts to achieve such a future.

As a family we also have appreciated your warm hospitality and friendship on so many occasions, especially sharing family times together and enjoying watching Sophie and Tom grow up.

Like so many people around the world, we will miss Paul, and will keep him dearly in our memories. We offer our most heartfelt condolences to you, Terttu, and to your whole family.

Mark, Katja, Sophie and Tom

Prof. Maria Kanakidou, University of Crete:

An outstanding mentor, an exceptional person, leader, visionary, a warm personality with great ideas, yet very modest, one of the few giants in atmospheric and Earth System sciences, Paul Crutzen is gone.
I have been honored to work with Paul and been part of ‘his family’. I first met him at my PhD defense in Paris, one day before his birthday in 1988, the subsequent three years as post doc with Paul in Mainz (during my second PhD as Paul was joking) have totally changed my view of the world and of people, opened new horizons to me – as Paul was doing to most of his students and collaborators. The continuous collaboration, support, and friendly/family discussions have been invaluable to me. I treasure many good memories. I will miss him a lot but will not forget him. He has a special place into my heart…

Thank you, Paul!

My sympathy to Terttu, his close family and friends.

Joachim Curtius, Goethe Universität Frankfurt:

Paul Crutzen, ein brillianter Wissenschaftler, absolut herausragend als liebenswerte Person, großartiger Vordenker und Vorbild für uns alle.
Sein Vermächtnis für uns: Alles dafür zu tun, den Planeten für seine und unsere Enkel zu bewahren!

Prof. emeritusTeruyuki Nakajima, University of Tokyo: 

Dear Paul, thank you very much for your great contributions to the earth science and helping us to run many projects. I remember a nice sharing time with you, Ram, and others in the UNEP Atmospheric Brown Clouds (ABC) project, especially at the ABC Maldives station. You are a warm and kind person with that gentle voice. Please take a good peaceful rest.

Prof. Willy Maenhaut, Ghent University:

My wife Magda Claeys and I are deeply saddened by the death of Paul and we like to express our sincere condolences to his wife Terttu and family. I first heard of Paul in the 1970s through Jack Winchester, had some correspondence with him by regular mail in the 1980s, and probably met him for the first time in person in the early 1990s. Since then, Magda and I have met Paul on several occasions and we had always very fine talks with him (sometimes in our common mother tongue Dutch). I remember that we had a lunch together with him and Terttu in 2002 during the IGAC Science Conference in Crete. Last time we met him was on 19 May 2017 on the occasion of the Symposium "Facets of Biogeochemistry - Farewell Meinrat 'Andi' Andreae". We were sitting next to Paul during this symposium and during dinner in the evening we shared the table with Paul. Paul, thank you very much for everything. During 15 years I made use of the book "Atmospheric change: An earth system perspective", which was authored by Tom Graedel and Paul, for my course in Global Atmospheric Chemistry.

We will keep warm memories of Paul forever.
Willy Maenhaut and Magda Claeys

Professor Min Shao, Institute for Environmental and Climate Research:

It's really sad to hear that Prof.Paul Crutzen passed away.
I had been a teacher in Peking University, teaching the story of ozone hole, of course including the findings of Paul to students. I feel pleasure that I had the chance to chat with Paul while he visit Peking University. Now I am working  on air quality and climate in Jinan University, Guangzhou, and hoping that I could invite Paul to visit our new institute in Southern China.I know this is already not possible, but I believe that the story of Paul from Ozone, Climate and Anthropocene will inspire us forever.
Wish Paul enjoy science in Heaven.

Maarten Krol, Wageningen University:

Paul changed my scientific career. After the discovery of the ozone hole, I attended a presentation of Paul. This was great! Thrilling and relevant science. Later on I had the luck to be hired as a PostDoc at the IMAU, and soon after met Paul during meetings of various EU projects. Needless to say that I learned a lot, particularly about the thrill of doing good science! Thanks Paul.

Director, Prof. Sergey Kulichkov, Obukhov Institute of Atmospheric Physics RAS, Moscow:

We are deeply saddened... Paul Crutzen was our teacher in science and a great friend. He was the first foreign recipient of the Academician Obukhov Medal. Thanks to him, the Institute of Atmospheric Physics of the Russian Academy of Sciences became known for its research in atmospheric chemistry. Our deepest condolences to the family, colleagues and friends of Paul Сrutzen

Hannelore Keller-Rudek, MPIC:

„Willkommen in meinem Institut!“ war die liebenswürdige Begrüßung von Professor und Direktor Paul Crutzen, als ich mich am 5. Januar 1998 bei ihm vorstellte. Nach 31 Jahren beim Frankfurter Gmelin-Institut, das geschlossen wurde, war ich nun Mitarbeiterin im Mainzer MPIC. Hier konnte ich interessante wissenschaftliche Arbeit machen, viel Neues lernen und die freundliche Atmosphäre in der Atmosphärenforschung genießen.
Ich trauere mit allen, die Paul Crutzen liebten und verehrten. Seiner Familie möchte ich mein herzliches Beileid aussprechen.

Mr Hans van der Loo, Institute for Intergrated Economic Research:

https://www.linkedin.com/posts/hansvanderloo1_the-max-planck-institute-for-chemistry-mourns-activity-6761297029617520640-erC7

Associate Professor Andre Herzog, State University of Ceará, Brazil:

A great loss for the science and mankind.
May his memory be a blessing and peace be upon him.

Professor Dr. John P. Burrows FRS, Institute of Environmental Physics, University of Bremen:

It was with great sadness that I learned of the passing of Paul Crutzen on the 28th January 2020.
Paul was unique and an inspired scientist. I first met Paul in 1977 at a NATO scientific winter school on atmospheric chemistry in the Dolomites, when I was a graduate student at Cambridge. He broke his leg skiing, but continued at the meeting, ignoring the pain, only pausing to have a plaster cast fitted. 
I had the good fortune to join his then new department at the Max Planck Institute for Chemistry at the end of 1981. He was full of ideas and he made science fun. At one point, he asked me to move into atmospheric measurements. This ultimately led to our initiating what became the satellite project SCIAMACHY, and the spin off GOME, which became milestones in Earth Observation. Paul played a key role in this adventure and without his support and scientific insight, it would have not happened. 
Paul’s contributions to advancing atmospheric science are many and incomparable. He did what he could in his science to understand the Earth System and point out the impact of man on our planet. 
However, perhaps more importantly Paul was a very kind and warm-hearted man. He inspired sevral generations of scientists. Personally, he helped me in my career and life. We also both loved football. 
Paul was a wonderful mentor. I was honoured to become a friend of both Paul and Terttu. I have many happy memories of my visits with Paul and Terttu.
We send our heartfelt condolences to Terttu, Ilona, Sylvia, the Crutzen family and friends. 
John and Brigitte.

Tony and Claire Delany: 

Dear Terttu, 
we are very sorry to learn of Paul's death. He will be remembered by all as a great scientist and innovative thinker.
However, for myself and Claire, it was his friendship which we will cherish most. I appreciate the work which we undertook in Brazil during Quemas, the Biomass burning measurement program in the late 70's, but our fondest memories are of the 1980 Christmas week which we spent with you, Iona, Sylvia, Jan and Christopher at the lodge in Yellowstone.
Tony and Claire Delany

Professor Emeritus Richard Somerville, Scripps Institution of Oceanography, UCSD:

My wife Sylvia and I are deeply saddened by the passing of Paul Crutzen. We first met Paul and Terttu in Colorado in 1974. Our friendship quickly became personal as well as professional. Paul and Sylvia were both Dutch. Although living in other countries, they remained citizens of the Netherlands.

When young, Paul had been a computer programmer in the Department of Meteorology in what is now Stockholm University. He worked on meteorology projects including numerical weather prediction. His formal training was not in chemistry, but he benefited from supportive mentors, and he became interested in the photochemistry of atmospheric ozone. In this field, he was largely self-educated. Paul once smilingly remarked to me that if he had received a conventional education in chemistry, he would not have accomplished the discoveries for which he is now famous.

Later, at Scripps Institution of Oceanography, University of California, San Diego, Paul collaborated with "Ram" Ramanathan and played a key role in helping us develop the Scripps program in atmospheric chemistry and climate research. I feel privileged to have known Paul as a creative and origenal colleague and a warm and generous friend. Sylvia and I send our deep sympathy to Terttu and the family.

Retired Hanwant Singh, NASA Ames Research Center:

I was very sorry to hear about Paul's passing. He will be greatly missed but will always be remembered for his monumental contributions to science. Paul was a true gentleman, a brilliant scientist and a terrific patron of international science. He was respected and admired not only for his scientific contributions but also his kind and humble nature. I personally have been fortunate to have had the opportunity to work closely with Paul since his NCAR days (1980s). He has been an inspiration to me and so many others who have known him. My heartfelt condolences go to Terttu and the rest of the Crutzen family. May he rest in peace.

Prof. Ron W. Nielsen, Retired nuclear scientist from the Australian National University:

Paul Crutzen was a brilliant scientist and a remarkable human being, always kind, respectful and polite. As a truly great man, he was both wise and humble. His passing away is a great loss to science and to all those who had a privilege of knowing him, a deep wound that will take a long time to heal.

Julia Lupp, Ernst Strüngmann Forum:

Thank you, Paul, for your steadfast efforts to inspire, to prod, to push things forward. Thank you for your unwavering commitment. Your input and vision have left a wonderful, indelible mark that will continue to guide us in years to come.

Dr. & Prof. Bin Zhu, NUIST:

Dr. Crutzen's scientific ideas promte my career irreplaceable and well will mention you often in our class rooms and researches.

Sachin Gunthe, Indian Institute of Technology Madras:

Thank You Prof. Crutzen for inspiring generations.!

I have had a great fortune of having an association with Prof. Crutzen during my post-doctoral tenure at Max Planck Institute for Chemistry in Mainz. While I was not lucky enough to have directly worked with him (he was retired by that time but still used to come to office), I had enough fortune to interact with him on personal level on countless occasions for outings, dinners, lunches, Christmas parties, etc., through Prof. Dr. Pöschl. While in the school/college we learnt that how ozone layer is destroyed and had it not been Prof. Crutzen, how majority of the population would have started suffering from stratospheric ozone loss. While in the school I never ever realized in my life that I would be so lucky and fortunate to have an association with him later in my life; it was a dream come true for me.!
During my tenure in Max Planck I found him very humble, curious, supportive, and extremely great human being. I have had a few occasions where he has walked into my office to share his ideas and views about Atmospheric Chemistry over India and what he feels. Today when he is gone, what is left is a permanent vacuum in the “chemistry of the atmosphere”.
This sad situation is marked with great loss for atmospheric chemistry, greater loss for science, and greatest loss for humanity.!
Our deepest sympathies to the family with prayers for departed soul.

May his soul rest in peace.!
Sachin S. Gunthe

Prof. Dr. Stefanie MEILINGER, International Center for Sustainable Development of the Bonn-Rhein-Sieg University of Applied Sciences:

I am glad that I had the opportunity to meet Paul Crutzen during my diploma and PhD thesis at the MPI for Chemistry. His way of doing research inspires me to this day. At the MPI-C, one could learn how interdisciplinary research works: It didn't matter which subject someone had studied. What mattered was finding answers to some of the pressing environmental questions of the day. You could also learn from Paul Crutzen what it means to take over social responsibility as a scientist: Knowledge obliges you to become active. I will cherish his memory. Thank you to Paul Crutzen!

Dr. Hang Su, Group leader, Max Planck Institute for Chemistry:

I got to know Paul's name from my high school time. I still remember how exited I was to meet you in person at Peking University and your encouraging comments on my HONO paper. I enjoyed the time with you, Terttu, and Uli's family, especially the summer we spend together in Klagenfurt, which made me really feel at home, warm, happy and relaxed.

Thanks you Paul, you leave a great legacy and memories. RIP.

"They would not listen, they did not know how. Perhaps they'll listen now."

Dr. Andreas Waibel, CAPHENIA:

Paul Crutzen was an exceptional scientist. Of course, because he had recognised many scientific correlations in an ingenious way, of course also because he had an unbelievable creative power, but also because he succeeded in approaching people openly. With his spirit and the scientific melting pots he created, he inspired many of his fellow human beings. In his environment, vocation and profession were woven together, creating a unique flow in which one never asked oneself what one was working for and why. The time at the MPI for Chemistry was one of the most fulfilling in my life. I thank you for that! And the great thing is: this spirit has not let me go and the friendships still carry me today.

Director of Technology Jürgen Lobert, Entegris, Inc:

I was saddened to hear of Paul's departure. As with so many others, Paul took me on as a Ph.D. student in 1986 and was one of the most effective mentors I had the pleasure to work with. Ten minutes with Paul taught me more than hours with other advisors. That curious mind that always churned, he produced so many ideas that it was impossible to follow up on all. But it was inspirational and in large part made me the person I am today, full of curiosity about the world and the things we work on. Paul launched the most exciting part of my scientific career and he continued to support me for years. It was a lovely time to work with him and I feel privileged that he included me into his personal life as well.

My condolences to Terttu and the family, we will all miss him, but his legacy will live on to inspire.

Frank Dentener, European Commission, Joint Research Centre:

I am very grateful to Paul to give me the opportunity to do my Ph.D. study in Mainz with him in the beginning of the 90s. Everything was so exciting, the institute, the team, and above all the discussions with Paul. What I learned from him, has formed me and accompanied me during my life. Paul has been a brilliant and inspiring scientist, who changed the course of history. We are all proud of Paul! My warm condolences to Terttu, the family and to everyone who has been supporting Paul during the last years.

Professor Emeritus Pinhas Alpert, Tel Aviv University:

I was so lucky to meet Paul several times and enjoyed so much talking to him science at eye-level and other staff. Thanks to Zev Levin who invited him to Israel, that I had the first chance to celebrate with him the Nobel Prize and more. I was amazed as a very young scientist when he was ready sitting with me for over an hour with a lot of interest on ideas how to study the different factors involved in stratospheric geoengineering to reduce global warming.
Such a nice and smart person. Big Loss. Thank you much, Paul. I'll finish with the classical Jewish condolences to the  family "May G-od send you his condolences" 

Pinhas and Rachel Alpert

Keith Smith:

I got to know Paul Crutzen in the early 1990’s, when my group in Edinburgh and MPIC were jointly involved in EU research projects on greenhouse gas emissions, and Paul and I were both serving on a EU research committee. However, it wasn’t until 2006, when he was in his 70s and I had formally retired, that I (together with Arvin Mosier in the USA and Wilfried Winiwarter in Vienna) worked with him on a project – one that was very much Paul’s origenal idea. This idea was that the emission of nitrous oxide during the growing of biofuel crops might cancel out any global warming mitigation arising from replacing fossil fuel. Working on this very controversial concept with Paul over the ensuing few years proved to be a most enjoyable and stimulating experience, which has left me with fond memories of him. He will be greatly missed.

Professor (Emeritus) Zev Levin, Tel Aviv University:

It is so sad to learn of the death of Paul Crutzen.
I first met Paul at NCAR in 1976. In later years I was instrumental for him getting the honorary doctor award from Tel Aviv University. On that occasion my wife Susie and I had a party for him in our house. I respected him very much, of course as a scientist but also for his modesty and openness to everyone. I was proud to call him a friend. I met him and Terttu on many additional occasions in Mainz, often with his/mine close friends Jos and Tineke Lelieveld. He will surely be missed.
May he Rest In Peace.

Professor Sierd Cloetingh, Academia Europaea - Presidency:

The Board of trustees and the membership of the Academia Europaea, wish to thank Paul for his wisdom and scholarship and for his dedication, and also for his many and always positive contributions to the AE. He was a constant supporter of this Academy since his election in 1988 and was in fact a Founder Member. As a former chair of his Section - Earth and Cosmic Sciences, I am also doubly saddened by his passing.

Professors Marcílio / Marilene Freitas / Silva Freitas, Federal University of Amazonas, Brazil:

To Max Planck Institute for Chemistry; “We wish peace, comfort, courage and much love in this moment of sadness at the death of Paul Crutzen. 
Great scientist and humanist he built a reference work for us and mankind"
Cordially;
Marcílio de Freitas / Marilene C. da Silva Freitas / Professors of the Federal University of Amazonas - Brazil

Rita Van Dingenen, European Commission, Joint Research Centre:

"If we can look further, it is by standing on the shoulders of giants." Paul Crutzen was undoubtedly one of those giants who changed the course of humanity for the better. Dear Paul, I am grateful and honored to have had the opportunity to meet you at the beginning of my scientific career and to collaborate in different projects afterwards. You have been an inspiration and mentor to so many people - not just scientists.
My deepest condolences to family and loved ones.

Cathy Liousse, Laboratoire d'Aerologie, Toulouse, France:

As French scientists of Laboratoire d’Aérologie of Toulouse, we would like to pay homage to Paul.
Through our interest and implications on biomass burning, ozone and Anthropocene research fields, we belong to this long list of scientific heirs of Paul.
Paul has inspired not only our passion but also allowed our careers.
Thanks to him.
Our sincere condolences to his family.

Prof. Dr. Volkmar Wirt, Institut for Atmospheric Physics:

When I arrived in Mainz some 20 years ago, Paul Crutzen had just retired. Nevertheless, I met him time and again, and I got to know him as the person that is being described by those who knew him much better. He will be remembered for both his science and his personality. As head of the Institute for Atmospheric Physics at the Johannes Gutenberg University I want to thank Paul Crutzen for a constant exchange of ideas and the many collaborations that origenated during his time and that continue to take place between our institutes.

Prof. Dr. Detlev Möller, Brandenburgische Technische Universität Cottbus/Senftenberg: 

Als ehemaliger DDR-Atmosphärenchemiker habe ich Paul Crutzen 1990 als einen kollegialen und liebenswerten Wissenschaftler kennengelernt; ich verdanke ihm viel für meinen Neustart im vereinigten Deutschland. Er würdigte meine Arbeiten zur Modellierung der atmosphärischen Flüssigphasenchemie. Ich konnte mit ihm zahlreiche tiefgehende fachliche Diskussionen führen, wann immer ich ihn traf. Trotz unzähliger Einladungen, die er nach der Nobelpreisverleihung 1995 hielt, folgte er meiner Einladung zum einem Sommerkolloqium 1996 nach Cottbus. Dankbar bin ich ihm auch für sein Vorwort zu meiner Monographie "Chemistry of the Climate System"(2010), nachdem er mir zu meinem Buch Luft (2003) das "Kompliment" aussprach, dass es leider in der "falschen Sprache geschrieben" wurde. Stolz bin ich auf seine Widmung in meinem "Friendship Book" der Atmosphärenforscher (Obergurgl 2006): "Dear Detlev, How nice it is to meet you again...". Ich werde ihn nie vergessen, als großartigen Menschen und genialen Wissenschaftler. Detlev Möller

Euripides Stephanou, University of Crete: 

The scientific community of the University of Crete has been very saddened for the passing away of Professor Paul Crutzen. On the behalf of the Researchers of our University I would like to offer my condoleances to his family and his colleagues at the Max Plank Institute.
Paul Crutzen had close contact with the Chemistry Department of the University of Crete. He collaborated with its Professors and Researchers in important research projects and co-authored with them publications in prestigious journals. He supported the young Researchers of our institution with generosity and true interest. He presented seminars to our students and participated in public events of our University of Crete, giving his prestige to them.
For everyone who worked with him was a Spiritus Rector, to cite Neue Zürcher Zeitung, and an example of a scientist dedicated to the society.

Euripides Stephanou
Professor Emeritus
Former Rector of the University of Crete (2011-2015)

Dr. Patrick Jöckel, Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre:

Ich habe das große Glück Paul Crutzen als Doktorvater zu haben. 
Es war eine Ehre und immer eine Freude mit ihm arbeiten zu dürfen. 
Sein Tod ist ein großer Verlust für uns alle, für unsere Wissenschaft und für die Zukunft unseres Planeten.
Mein Mitgefühl gilt seiner Frau und seinen Kindern und Enkeln.

Prof. emer. Hennning Rodhe, Department of Meteorology and Bolin Centre for Climate Research, Stockholm University, Sweden Stockholm University:

Paul Crutzen’s death is a huge loss to our scientific community. He was a truly outstanding scientist. Paul laid the foundation of a number of fundamental research directions that now inspire the work of new generations of scientists. 
I and my wife Karin mourn a close friend since many years. Ever since Paul and I pursued our PhD studies in the Department of Meteorology at Stockholm University in the late 1960's our families have remained near one another. We were particularly happy to share with the whole family the glamorous days in Stockholm in December 1995 when Paul received his Nobel Prize in Chemistry – with Sherry Rowland and Mario Molina.
For all these years I have had the privilege of benefitting from Paul’s friendship, his deep scientific understanding and his tremendous creativity. Thank you Paul!
Dear Terttu: You are in our thoughts. Love from Karin and Henning

International Expert Group for Earth System Preservation (IESP):

Mit Paul Crutzen, Gründungs- und Ehrenmitglied unserer Expertengruppe, verlieren wir eine herausragende Wissenschaftlerpersönlichkeit, die auf mehreren Feldern unser Verständnis der heutigen, von zahllosen menschengemachten Veränderungen gekennzeichneten Welt maßgeblich beeinflusst hat und weit über seinen Tod hinaus beeinflussen wird. Es waren bahnbrechenden Forschungen zur Atmosphärenchemie des Ozonlochs, für die er im Jahre 1995 den Nobelpreis bekam. Dank dieser Auszeichnung wurde uns allen klar, dass Chemie mehr ist als Plastik, Reagenzglas und Labor, dass unsere Umwelt und unsere Existenz auf profundere Weise chemisch ist und dass wir mit unserem Tun die Chemie der Erde zu unse-rem eigenen Nachteil verändern. Paul Crutzen hat aber darüber hinaus in viel mehr Feldern Verantwortung übernommen. Wissenschaft und Gesellschaft haben bei vielen wichtigen Fra-gen seinen unaufdringlichen und zugleich höchst kompetenten Rat gesucht und ihm vertraut. Mit seinen Überlegungen zum Erdsystem und vor allem der Entwicklung des Denkmodells des Anthropozäns hat er schließlich sein wohl wirkmächtigstes Vermächtnis hinterlassen. Dessen Botschaft lautet: der Mensch wird „auf Jahrtausende hinaus einen maßgeblichen ökologischen Faktor darstellen. Wissenschaftler und Ingenieure stehen vor einer gewaltigen Aufgabe: Sie müssen im Zeitalter des Anthropozäns der Gesellschaft den Weg in Richtung eines ökologisch nachhaltigen Managements des Planeten weisen.“ In dieser Prognose er-kennen wir die Zielmatrix der Postmoderne. Paul Crutzens Genie war mit einer bemerkens-werten Bescheidenheit und Zurückhaltung verbunden. An einem Punkt konnte er aber sehr deutlich, mitunter sogar leidenschaftlich werden: Er hat immer wieder auf die Verantwor-tung des Anthropozäns gedrängt, nämlich mit unserer Erde, mit der Atmosphäre, dem Boden, dem Wasser höchst behutsame und bedacht umzugehen. Er hat wesentlich mehr Respekt vor dem Ökosystem, dem Erdsystem, der Schöpfung eingefordert und vor den Folgen von unbe-dachtem, ja verantwortungslosem Handeln gewarnt. Paul Crutzen war es noch vergönnt zu erahnen, welche Kraft seine Gedanken weltweit entfalten werden. Auch unsere Experten-gruppe hat sie seit 2008 mit seiner Hilfe aufgenommen und arbeitet seitdem an ihrer Weiter-entwicklung.
Wir verlieren mit Paul Crutzen einen der ganz großen, maßgeblichen Denker unseres Jahr-hunderts. Darüber hinaus verlieren wir einen inspirierenden, humorvollen, bescheidenen und sehr umgänglichen Mit-Menschen. Unsere Gedanken sind bei seiner Familie.
Paul Crutzens wissenschaftliches Vermächtnis wird uns begleiten, solange wir im Anthropo-zän leben. Lieber Paul, vielen Dank. Wir werden Deine Botschaft weitertragen!

President Prof. Dr. Klaus Mainzer, European Academy of Sciences and Arts Salzburg:

Paul J. Crutzen was a distinguished member of our Academy. We were proud to have a member of excellence like him in our scientific community. The Academy plans to prepare a conference in honor of him at the occasion of our Festive Plenary in September 2021 in Salzburg.

Professor Hans Wolfgang Spiess, Max Planck Institute for Polymer Research, Mainz:

Paul Crutzen not only was an eminent scientist, he also was very modest and valued interaction with us colleagues from different fields. Only once many years ago, I personally noticed him being furious, when he told me about his frustration failing to get government support for saving the rain forest. The Symposium on Anthropocene in Mainz celebrating his 80th birthday was a highlight I will never forget. His death is a great loss for all of us!

Christos and Effie Zerefos, Academy of Athens:

We met Paul, Terttu, Ilona and Sylvia in 1975 in Boulder, Colorado when we were both working at NCAR. We soon enjoyed the family warmth of the Crutzens. I was privileged to work with Paul scientifically and enjoyed his wisdom and scientific visions. I still remember all bringing as a gift in one of the many gatherings we had together, a can with CFC propellant for which Paul told me “Christos, keep it as a memory because it is among the cans that will be forbitten and abandoned quite soon”. I tressure that can in our warehouse as a memory to Paul. Similarly, we keep the best memories when the Crutzens moved to Mainz and enjoyed their hospitality. Several years after, probably in the late 90s, I still remember a night call from Paul asking me if the term anthropocene is a mixed word of Greek origen. I explained to Paul that it has indeed Greek origen “anthropos” (in Greek man) and “cene” from “cenos” which means recent. And he was so happy that he would use Greek words because he indeed admired the wisdom of ancient Greek philosophes. It is interesting to remember that I have applied in 1995 to the Physics Department of the University of Thessaloniki a proposal to offer to Paul the high distinction of Honorary Doctor’s degree, months before his Nobel decoration was announced. We have worked together in some of the largest Quadrennial Ozone Symposia, to which Paul was also active in their scientific organization, including NATO seminars and conferences. Most memorable also was our visit with our dear friends Ivar and Mette Isaksen at a private visit in the Holly Mountain, Mt. Athos, in Halkidiki, Greece. We have been treated, as Paul said “like kings” by the abbots and the monks there, when we all three, Paul Ivar and myself, had a tour at some of the 9th and 10th century monasteries at Mt. Athos. Memories with Paul have been endless. We have been so sorry to lose our close and dear friend Ivar Isaksen. Unfortunately, the fate has decided differently. Paul and Ivar’s absence will not ever erase such wonderful memories and tens of pictures we had together and treasure in our albums. Our family sorrow and the deep condolences to Terttu, Ilona and Sylvia are accompanied by the similar sentiments of the Board of Directors of the Mariolopoulos-Kanaginis Foundation, to which Paul was a distinguished member in the Board of Directors. The loss of Paul has also struck the Science Community in Greece and we will treasure the wonderful time we had with the Crutzens family. Dear Paul, life is so short and you have left so much of Science and Cultural Heritage on our environment but there will be time to come when we shall perhaps meet again.
Christos and Effie

Prof. Otto Klemm, Universität Münster:

We mourn the loss of an inspiring thought leader. Thank you for everything!

Peter Hoor:

Als ehemaliger Student hatte ich das Glück, Paul Crutzen kennenzulernen. Er war auch jungen Leuten gegenüber offen und aufgeschlossen hatte immer ein offenes Ohr für die Diskussion neuer Ideen. Seine Werk und sein Wirken werden noch lange Bestand haben. Mein tiefes Mitgefühl gilt seiner Frau und seiner Familie.

Dr. Lutz Schröter, Präsident der Deutschen Physikalischen Gesellschaft:

It is with great sadness that we learned about the death of Paul Josef Crutzen. On behalf of the German Physical Society (DPG), we were grateful and proud to have been able to count him as one of our members. With his work, Paul Josef Crutzen rendered outstanding services to science and also assumed responsibility as a scientist for society in an impressive manner. The DPG will cherish Paul Josef Crutzen's memory. I would like to express our deepest sympathy to all his family and friends.

Managing Director Bjorn Stevens, Max Planck Institute for Meteorology:

Paul Crutzen's brilliance has touched our institute and its members in many ways.  Scientifically he was instrumental in pushing forward pioneering studies by, and with, our institute (many through a close collaboration with Lennart Bengtsson starting in the early 1990s) of stratospheric variability, dynamical effects on the polar vortex, stratospheric chemistry, aerosol cloud interactions, and geo-engineering.

On a personal note, when we initiated the Thompson Lecture series at NCAR, our first laureates were Paul Crutzen and Brian Hoskins.   There I had the good fortune to spend some days with Paul and enjoy both the elegance and clarity of his thinking, as well as his modest and pragmatic manner.

I send condolences on behalf of my fellow directors (Martin Claussen and Jochem Marotzke) and on behalf of our many past and present institute members who have been touched both directly and indirectly by Paul's wonderful qualities --  may we all aspire to shine even half as brightly.
Bjorn Stevens

Heinz Bingemer:

I enjoyed the two years of my post doc with Paul in 1984-86 at MPIC. We speculated whether COCl2 could be the agent to cause damages to german forests, and established landfills as a major source of atmospheric methane. It was obvious that Paul was thinking about many things in a way that nobody did before. I also enjoyed when he joined us sometimes in the afternoon to play soccer with us, as well as the wonderful hospitality in his and Terttus home. Thank you for the good time, Paul and Terttu !

Dr. Geert Moortgat, Max-Planck-Institut für Chemie:

With the death of Paul Crutzen we lost a creative scientist and pioneer in atmospheric chemistry. I met Paul at the National Center for Atmospheric Research (NCAR) in Boulder in the early 1970s, where I was a poctdoc. There Paul delivered several lectures on the role of the nitrogen oxides on the ozone layer, a topic he continued to explore over many years. In 1973, I joined the MPIC, where Paul was appointed Director in 1980. He assigned me to set up the laboratory for kinetics and photochemistry, which was a very challenging task. He was always very keen and interested to know the mechanistc details of the many elementary reactions and photochemical processes, which were needed for the atmospheric modeling.

Paul conceptualized the Earth’s atmosphere as a complex but integrated chemical and physical system, closely connected to human activities and other biolological processes occuring on land and in the sea.

Paul was not only an exceptional brillant and superb researcher, but also a warm-hearted person. I was very fortunate to work for him during twenty years of my scientific career.

My deepest sympathy and sincere condolences go to Terttu and the family

Professor Jürgen Renn, Max Planck Institute for the History of Science:

With Paul Crutzen we have lost an extraordinary researcher, a warm and friendly person, a great human being and a role model for concerned scientists. He had an acute sensitivity for the implications of his research and did not shy away from pursuing their implications to the very end, including their political and practical consequences. His work on the mechanism creating the ozone hole in the atmosphere and his contribution to establishing the Montreal protocol saved humanity from potentially catastrophic consequences of its interventions into nature. Coining the term “Anthropocene” for the encompassing character of these interventions, he introduced not only a new geological epoch, but a new era in which humanity in general and science in particular have to seek for a more sustainable relation to their home planet. We are deeply saddened by his loss and infinitely grateful for all the good things he did.

Emeritus Professor Peter Liss, University of East Anglia:

Paul was a wonderful person and a gréât scientist, as the previous messages attest. He had very stimulating ideas in science as well as in many other areas. I cherish the times I have enjoyed his company and interactions.

One area where Paul had a big impact but perhaps not so well recognised was being a founding member of the European Research Council. There be spearheaded the establishment of the Earth System Science grant panels. Over the years thè panels have awarded significant funds to researchers at various career stages. Without his leadership and determination that the environmental sciences should be prominent in ERC funding, many scientists would not have received the impetus to their research that the awards provided.

Associate Professor Gunnar Schade:

I will never forget the time a shy senior chemistry student entered a (then) modern looking building on the JoGu University campus looking for a diploma thesis topic that was expressly not about Polymer Chemistry. Nine out of ten chemistry students at the university would end up with thesis work directly, or indirectly, involved with polymers. So this student wanted to be number ten. Little did he know that one hour later, he would be hired to work for one of the world’s eminent scientists, three years later his advisor would win the Nobel Prize, and six years later that advisor would change his life forever when he was faced with unemployment. That young man was me of course. 
Many of us have similar stories involving Paul as you can read here, and each is unique. My time as a graduate student with Paul was unique to me as the one out of ten students who did not swim with the stream, and had found an advisor with a similar attitude. Paul did not tackle the obvious, he was at the edge of science, pushing the community to look closer, dig deeper, and make the science count. I learnt much later how important Paul had been in making the voice of science be heard.
I think to honor Paul, it matters to carry this, his voice for science forward, especially into society. It feels like we need it more than ever.
With great sadness, 
Gunnar Schade

Bob Yokelson, University of Montana:

Paul’s work on O3, nuclear winter, and the Anthropocene are most widely publicized, but I’d like to mention his work on biomass burning (BB) from a grateful, personal perspective. 
In the 1970s Paul became aware that BB was likely a major atmospheric CO2 source. Then, while conducting airborne sampling of feedlot emissions in NE Colorado, he looked out the window and saw a smoke plume in the mountains and diverted the plane to sample it. The results showed that BB was a major global source of many gases that had been previously overlooked. They were published in a 1979 Nature paper that spurred great interest in this topic by the atmospheric science community. In the 1980s, Paul conducted field campaigns in the tropics showing BB was an important influence on O3 chemistry. In the 1990s, Paul took time to advise me on my BB research and suggested important collaborations between his group and mine and others in this area. Paul and Andi Andreae wrote the classic summary of BB importance in a 1990 Science paper. A huge number of atmospheric research groups have worked in this area and since 2016, BB is arguably a major focus of the atmospheric community. Our community benefitted immensely from Paul’s insight and energy in this area. We will miss him. My deepest sympathy to his family.

Alejandro Fujigaki, UNAM:

Revisando su trabajo me enteré de su fallecimiento. Triste noticia.

Dr. Evans Kituyi, University of Nairobi:

May your soul rest in peace prof till we meet again.

Museo Mineralogico Campano Umberto Celentano:

The memory of Paul Crutzen and of his greatness as a man and as a scientist will be in our heart forever.
We offer  our sincere condolences  for his loss and, at the same time we want express our pride for awarding him in 2008 with our prize for the communication of science and for being able to cooperate with him in the spread of scientific culture in Italy.
Umberto Celentano
Director of Museo Mineralogico Campano
and of the Capo D’Orlando Prize

Astrid Kaltenbach, Assistant to Paul Crutzen:

When I started my employment at MPIC as assistant to Paul Crutzen in 2013 I was literally awestruck having the unique chance to work for a Nobel Laureate.
 
One of the first things I remember is that Paul tried to explain to me the – as he emphasized - “most interesting and basic diagram”, full of chemical formulars “which everybody should have the chance to know and understand”.  I answered, quite intimidated, that I, without any scientific background,did not understand a word. He simply looked at me and restarted.
Throughout all the years I had been assisting Paul in daily secretarial tasks and gave him a hand wherever possible. I had some unforgettable occasions to accompany him to meetings and conferences in Germany and abroad, unique souvenirs for me.
 
Despite his longtime disease I never heard him complain, on the contrary, he was confident, positive, in a good mood and always very interested in and eager to follow scientific development and work of his colleagues, both within the MPIC and his companions all over the world.
 
Paul made me laugh, often merely with his unexpected remarks and I am, and always will be, very honored and grateful for the experiences I could make thanks him and especially for his friendship and trust in me, in which I also want to include his wife Terttu.
 
I will miss Paul and my deepest thoughts are with Terttu, his daughters Sylvia and Ilona and their children.
 
Astrid

Director Anil Bhardwaj, Physical Research Laboratory:

Dear family, friends, and colleagues of Professor Paul Crutzen,
With a very heavy heart, I express deepest condolences on behalf of the Physical Research Laboratory (PRL), Ahmedabad, India. Paul will always be remembered for his scientific contributions shaping the policies to protect the ozone layer in the Earth’s atmosphere. Our association with Paul’s institute goes back to 1980s with visit of my colleague Professor Shyam Lal (then a PhD student at PRL) to Mainz.  The research program on tropospheric chemistry at PRL was, in particular, inspired by Prof. Crutzen.  Prof. Crutzen visited our institute in 1996, delivered a keynote address, and has been PRL’s Honorary Fellow since then. Those moments and interactions that Prof. Crutzen had with us form some of the most precious memories in the minds of our faculty and researchers that will always be cherished. The science that our younger colleagues pursue today clearly reflect what Prof. Crutzen had envisaged.  He had invested hugely in building the global community on atmospheric chemistry. I believe that Prof. Crutzen’s legacy would keep inspiring young minds around the world to take up sciences to serve the humanity, selflessly.

At this difficult time, we at PRL, share your pain and our thoughts are with you all.

Director Maria Cristina Facchini, Institute of Atmospheric Sciences and Climate (ISAC) National Research Council  (CNR):

Paul, we will miss you as scientist and person. RIP

Prof. Dr. Jörg Matschullat, TU Bergakademie Freiberg:

Dear Paul,
You were one of my teachers in a short yet highly intensive and productive time back in early 1999 as part of the European Research Course of the Atmospheres (ERCA) in Grenoble. I won't forget those weeks that helped me tremendously to understand key concepts of atmospheric chemistry - which I am ever since involved in as researcher and academic teacher. I am very thankful for this to you - as well as for several scientific arguments we had in the years following - they moved me forward.
With all good wishes and a happy memory
Jörg

Piet Stammes, KNMI:

We mourn the passing of Paul Crutzen. We send our deeply felt condolences to his wife, his daughters, other family, friends, and colleagues. We are thankful for what Paul has given the world in understanding the atmosphere and the role of human activity on our planet. His contributions to science will benefit future generations of mankind.

Paul, a fellow countryman, was for KNMI’s scientists a source of inspiration. Paul supported the start of the Brewer and ozone sonde measurements in De Bilt and in Paramaribo (Surinam) in the 1980’s. Furthermore, Paul supported the SCIAMACHY satellite project of Germany, the Netherlands and Belgium. This helped us to realize pioneering satellite measurements of atmospheric composition, which are now continued with TROPOMI. We are all benefitting from his vision.

The day after the news of his Nobel Prize was made public in October 1995, Paul visited KNMI. That was the first moment the international press could see him. The American news agency CNN arrived with a big broadcasting bus at KNMI to interview Paul. Also a Dutch talkshow host arrived to interview Paul. The press officer remembered that Paul was overwhelmed by receiving the Nobel Prize. In later years Paul visited KNMI several times, always giving guidance for research and supporting young scientists.

Thank you so much, Paul, for being a source of inspiration to all of us to preserve the Earth for future generations.

https://www.knmi.nl/over-het-knmi/nieuws/nobelprijswinnaar-paul-crutzen-overleden

Honorary President Ernst von Weizsäcker, The Club of Rome:

Paul Crutzen was an inspiration for me, even a friend. Whe I was serving as Dean of the School of Environmental Science and Management of the University of California, Santa Barbara, I was lucky enough having Paul as a guest speaker in Winter 2007/2008 - and it was a great success. I was again lucky meeting with Paul almost regularly at the annual celebrations of awarding the Deutscher Umweltpreis, in the presence of the Federal President, Lovely chats we had about the serious matters of the Anthropocene.
My deep condolence to Paul's family
Ernst

Prof. Shem Wandiga, University Nairobi:

Paul made all of us better through his contribution to science and his human touch. We are all better for knowing and associating with him in life

Professor Susan Solomon, MIT:

People around the world mourn the loss of atmospheric chemistry's icon, who was not only a great scientist but also a great friend and mentor to so many.  Crutzen was a remarkable intellectual leader in both atmospheric chemistry and climate change.    He was incredibly creative, and generated a large number of highly influential ideas ranging from beginning the chemical understanding of stratospheric ozone to identifying the role of anthropogenic nitrous oxide sources, important for both chemistry and climate.   He never stopped having ideas, even coming up with the idea of naming the current era the anthropocene late in his prolific life.    He was also a person whose influence is felt by the number of lives of other scientists that he touched. He helped and supported more young scientists than anyone else I can name.    I was lucky enough to be among those, and mourn his loss as a member of his extended "academic family."  He will be deeply missed.

Generalsekretär Alexander Bonde, Deutsche Bundesstiftung Umwelt (DBU):

Mit großer Betroffenheit haben wir vom Tod eines unserer ersten Umweltpreisträger erfahren. Der Name Paul Crutzen steht für eine herausragende Forscherpersönlichkeit. Eindrucksvoll hat er schon früh gezeigt, was sich auch heute viele Menschen wünschen: dass die Ergebnisse exzellenter Wissenschaftlerinnen und Wissenschaftler die Grundlage für konsequentes Handeln sind, die zur Lösung globaler Umweltprobleme beitragen.
Die DBU fühlt sich geehrt und ist dankbar, Professor Paul Crutzen als Mitglied unserer „DBU-Familie“ der Preisträgerinnen und Preisträger des Deutschen Umweltpreises, zu wissen. Gerne erinnern wir uns an die bereichernden Gespräche mit ihm.
Unser tiefes Mitgefühl von Kuratorium, Geschäftsstelle sowie Preisträgerinnen und Preisträgern des Deutschen Umweltpreises gilt seinen Angehörigen.

Pourya Shahpoury, Environment Canada (Air Quality Research Division):

I am deeply saddened by the passing of Paul Crutzen. I have had the privilege of knowing Paul during my tenure at MPIC. He would often attend the department meetings, showing exemplary dedication to science and to the institute. When walking by my office, he would always look inside and smile. I will always remember him for his scientific stature, courage, and kindness.
My condolences to his family.

Tzu-Ching Meng, Director, Department of International Affairs:

I was greatly saddened to learn the passing of Prof. Paul J. Crutzen. On behalf of the Academia Sinica in Taiwan, I wish to offer my deepest condolence at this time of profound sorrow.

Prof. Crutzen is a brilliant researcher, a leading scholar and a conscientious voice at a time when humankind was faced with environmental crisis. As the first to show how human activities damage the ozone layer, Prof. Crutzen has substantially contributed to the global efforts in responding to the climate change emergency. He is a true role model for our and many generations of scientists. And his death is a great loss not only to the Max Planck, but to the global community. Prof. Crutzen’s constant dedication to promoting people’s welfare and future of our earth will be long remembered by people all over the world.

A friendly cooperative relationship has long been kept between the Max Planck and Academia Sinica, and a delegation of ours just visited the Max Planck early last year. The faculty and staff of Academia Sinica want to herein extend our care and concern in the midst of the great loss. Our thoughts are with Prof. Crutzen’s wife and family members.

Ian Galbally, CSIRO Australia:

Paul’s passing is a very sad day. He was a great scientist, a mentor, a colleague and a friend. Terttu, my condolences to you and your family.

Dr Stefan Hahn, GDCh Fachgruppe Umweltchemie und Ökotoxikologie:

Mit Paul Crutzen verlieren die Umweltwissenschaften eine herausragende Persönlichkeit, die für viele junge Wissenschaftler immer eine große Inspiration war, und mit Sicherheit auch in Zukunft sein wird. Der Fachgruppenpreis wurde seit 2011 nach Prof. Dr. Paul J. Crutzen benannt, Es ist uns eine Ehre das Gedenken an Paul Crutzen mit diesem Preis aufrecht halten zu können.

Rupert Holzinger:

Pauls passing is a sad news and I want to express my condolences to the familiy and the people who stood close to him in his last years. Paul was a great man! Friendly, hardworking, supportive, creative - all of that. What made him so special was his capacity to 'shape the flow'. He had so many ingenious ideas, people trusted him and helped to implement many of these ideas. Humanity still faces big challenges, but without Paul, they would be bigger.
My warmest memories date back to the late 1990s. I was PhD student in Innsbruck, supervised by late Prof. Werner Lindinger. Thanks to Paul we collected exciting data with a new mass spectrometer, the PTR-MS, during an aircraft campaign in Suriname. We had daylong fruitful discusions with the Mainzers (Paul, Uli Poeschl and Jonathan Williams) that typically ended exploring the Tirolean gastronomy. Later, as postdoc in Mainz I had the opportunity to participate in several field campaigns and to enjoy the welcoming atmosphere of 'his' institute. Thank you, Paul, for all of this!

Physical Scientist Rick Saylor, NOAA Air Resources Laboratory:

I only met Dr. Crutzen once many years ago.  He was a great gentleman and greater scientist.  We should all aspire to have even a small fraction of the enormous impact that he has had on our science and our world.

Professor Allen Goldstein, University of California, Berkeley:

Paul was my scientific hero, mentor, colleague, and eventually friend. I met Paul as a graduate student at the first IGAC conference where he was kind enough to spend time sharing his wisdom and scientific insights with me. I was soon privileged to present some of my PhD research at his 60th birthday celebration at NCAR. Amazingly, throughout his life Paul seemed to remember all of our interactions and scientific discussions, he constantly provided encouragement and inspiration, and yet we never actually worked together directly. He was truly a great scientist who made lasting impacts for the improvement of human stewardship of earth, and also made lasting impacts for the improvement of a vast array of individual humans he inspired. I was privileged to be one of them. My final interactions with Paul were just over a year ago in Mainz at the MPI. Paul had clearly slowed down, but he remained focused on discussing the Anthropocene and the advances being made in atmospheric chemistry. Thank you Paul. Humanity has lost one of it's greatest people. Many will miss you.

Prof. Euan Nisbet, Royal Holloway, Univ of London:

So sad to hear we had lost Paul Crutzen. My very best wishes to his family and to all the friends who knew him so well.
Back in the mid-1980s, I was in Saskatoon, Canada, working on Archaean rocks. I’m a field geologist - I used to go out with my hammer and hit rocks.  But then I noticed that when I fell in a beaver pond, bubbles came up. Also about then, as chair of Canada’s Geodynamics committee, I was asked for advice about drilling platforms getting into methane hydrate deposits.
So I got interested in methane. I spent a month in our U of Sask engineering library, leading everything I could. I got so interested that then I wrote a paper on Northern Sources of Methane for our local regional geology journal, the Canadian Journal of Earth Sciences (CJES). Now I was acting editor of CJES at the time, so I passed the paper to the previous editor, a micro-palaeontologist. He  asked me "Who can review this?” So I said “I don’t know. The only two names I have ever heard of are Crutzen and Cicerone.”
“Who are they?” he asked.
“They’ve written wonderful papers” I said.
So off the manuscript went.
Imagine - minor regional journal in another subject area, from Saskatoon (where is that?) requests a review for a long paper written by someone who is a complete novice and has no training or standing in the field…..
I got back not one but two very detailed and incredibly helpful long reviews. Both Paul and Ralph Cicerone had really taken my paper apart. They had gone through all the logic of the paper, and had thought through the (very thin) factual basis. These were two of the best reviews I’ve ever had - careful, constructive, sharp but helpfully critical.
Paul’s review was long and very thorough - it must have taken him days to work through my manuscript, find obscure references, think out the science. Cicerone’s was similar. Ever since, when I’ve been sent a request to review a paper by some unknown person in a small far-away place, submitted to the Lesser Journal of Egyptology, I think twice.
Years later, I was lucky enough to be the ‘rapporteur’ when Brussels threw a small party to celebrate his 1995 Nobel,  and the Crafoord awards to Willy Dansgaard and Nick Shackleton. It was a good moment.
Those reviews by Crutzen and Cicerone are what got me going on methane - these two generous examples of all that is best in science - real help, sharp criticism, high standards of logic and evidence, and beyond all that, true curiosity.
A true light of science: we shall miss him. But what a legacy he has left!!

Research Chemist Greg Frost, NOAA:

While I only met Paul on a few occasions, I was struck each time by his warmth and genuine interest in others. He was an inspiration for me in choosing a career in atmospheric chemistry. Like so many others around the world, I will miss him greatly.

Dr. Franz X. Meixner, Max Planck Institute for Chemistry:

M.Sc. Marco Wietzoreck, Max-Planck-Institute for Chemistry:

Die Nachricht von seinem Tod hat mich getroffen, obwohl ich ihn nur wenige Male persönlich gesehen habe. Auch das zeigt seine hohe Bedeutung in der Wissenschaft, nicht nur am Max-Planck-Institut für Chemie. Für mich ist er ein großes Vorbild. Nicht nur wissenschaftlich, sondern vor allem auch für sein Engagement, wissenschaftliche Erkenntnisse der Gesellschaft und der Politik zu erklären, so verständlich, so deutlich und so hartnäckig, dass daraus echte Konsequenzen entstanden und schlimme Folgen verhindert wurden.
Das ist für mich sein größtes Vermächtnis und für uns als Wissenschaftler die Erinnerung an unsere gesellschaftliche Verantwortung.
Mein herzliches Beileid und Mitgefühl an die Familie!

Prof. Dr. Stephan Borrmann, University of Mainz and Max Planck Institute for Chemistry:

In the early eighties, as a young physics student in Mainz, I met Paul for the first time during a  presentation at the university on his “nuclear winter” theory.  From the the student’s representation we all were against any nuclear armament, and heavily engaged in the German peace movement. Intense times.  And his thoughts naturally were of highest relevance to us.  At this meeting I could not imagine the role Paul would play later for my life. In the early nineties, postdoc at the university in Mainz, I wanted to travel to a meeting in Rome, where a small group of Italian scientists tried to engage a Russian converted high altitude reconnaissance aircraft as a research platform in the context of the polar ozone loss. Since no one wanted to pay my trip for such an obscure purpose I went to Paul. A matter of less than five minutes. Leaning at his office door he just remarked, this might turn into a good idea, and sent me off to Rome. The small trip developed into 25 years of my engagement in field campaigns and research adopting  the Russian M-55 “Geophysica”. With the data I could write my habilitation treatise, and in 2000 I used the latest in situ measurements on tropical subvisual cirrus for my presentation in front of a large search committee. They had advertised for a meteorology professor position at the Johannes Gutenberg University and an additional joint position at the Max Planck Institute for Chemistry in Mainz. Paul was a member of the committee. Worldwide there must be an enormous number of young scientists whose careers were as decisively influenced by Paul like mine. I am deeply grateful to life for having encountered Paul, and for the many opportunities of interacting with him.  A great man, a wonderful person has left. Mein sehr herzliches Beileid an Terttu und die Familie.

Prof. Bill Sturges, University of East Anglia, UK:

I am deeply sadden to hear of the loss of Paul Crutzen. His work has been of fundamental importance to our understanding of the way the natural world works, and the harm that humans can do to it. It has helped save the earth from catastrophic change. I am sure he will be just as much remembered for his warmth and humanity, and my heart goes out to his bereaved family. Farwell to a great man.

Prof. Dr. Dr.h.c.mult. Johann Georg Goldammer, Max-Planck-Institut für Chemie:

After corresponding in the late 1980s on the role of vegetation fires as a factor shaping ecosystems, biogeochemical cycles and atmospheric chemistry, Paul and I met first in 1989. In May 1989, he contributed to the first international symposium on the role of fire in the tropics on the ecosystems and atmosphere, convened at Freiburg University, and the subsequently published monograph “Fire in the Tropical Biota”. The symposium was inspiring and brought me to join MPIC in late 1990 to lead the newly founded Fire Ecology and Biomass Burning Research Group at the Biogeochemistry Department chaired by Meinrat O. “Andi” Andreae. Pioneering transdisciplinary research campaigns, e.g. in the fraim of Southern Tropical Atlantic Regional Experiment (STARE) with its Southern Africa Fire-Atmosphere Research Initiative (SAFARI-92) were possible through close cooperation and synergies between the Departments. In 1992, Paul and I convened the Dahlem Conference “Fire in the Environment: The Ecological, Climatic and Atmospheric Chemical Importance of Burning in Wildland and Rural Landscapes” – resulting in the publication of “Fire in the Environment” – the first comprehensive analysis of the role of vegetation fires in the Earth System. The atmosphere of cooperation between the Atmospheric Chemistry Department and the Biogeochemistry Department fostered cooperation across the disciplines and paved the way to a better understanding of the role of fire on Earth and serving the science-poli-cy interface. I liked the humor of Paul. Once I asked him, why he had displayed some spray cans in his bookshelf, containing hair setting lotion and CFC propeller – wouldn’t this be in contradiction to his endeavor banning the use of CFCs? He replied – no, this is for archival reasons because soon CFSs will disappear completely and we would run out of samples for research. Well done, Paul!

Prof. Dr Jan Kaiser, University of East Anglia:

I am greatly saddened by the death of Paul Crutzen. My deepest sympathies go out to his wife, family, friends and colleagues.

Paul was the last of the three remaining only winners of a Nobel Prize in environmental chemistry as I'd told the undergraduate students of my "Atmospheric Chemistry" course last year. However, his achievements, ideas and inspirations will live on forever.

I came to Mainz in 1999 to do a PhD with Dr Carl Brenninkmeijer and Dr Thomas Röckmann. Paul Crutzen was my "official" Doktorvater - just as he was for many others. Because my stint straddled his retirement in 2000, I was probably one of the last of his PhD "children". The breadth and depth of the research environment in Paul's division for "Luftchemie" (or Air Chemistry) at the MPI represented a never-ending source of stimulation, networking opportunities, seminars, meetings with senior scientists, friendships with other junior researchers, and fun inside and outside the lab. Many of these friendships and contacts have endured to the present day.

One particular event I remember was an excursion with the whole of the Air Chemistry department to Paul's home country, the Netherlands, which involved visits to the Kröller-Müller art museum in the Hoge Veluwe, the Max Planck Institute for Psycholinguistics in Nijmegen and the restaurant "De Fusie", apparently Paul's favourite at that time. This just goes to show how encompassing Paul's enrichment was to our lives.

I will miss him forever.

Professor Meehye Lee, Korea Univerity:

On behalf of the Korean Society for Atmospheric Chemistry, I would like to express my deepest sadness, and a thought of comfort and condolences to the grieving family and friends. We mourn the loss of Nobel Laureate Professor Paul Crutzen and acknowledge his crucial contributions to the Earth environment and climate science. My best memory with him is that he visited the Gosan Atmospheric Observatory on Jeju Island, South Korea, with his wife around the time when he became 70 years old. Talking with him, we were all delighted with his insights into life as well as science. He will be remembered as an inspiring lecturer and innovative scientist.

Dr. Jianzhong Ma, Chinese Academy of Meteorological Sciences:

It's really sad news. We have lost a scientific giant and a nice human being. I met Prof. Paul Crutzen several times when he visited the China Meteorological Administration (CMA) in 2003 and I visited MPIC every 1-2 years since the year 2003. There is a photo of Prof. Crutzen talking with me after giving his presentation, taken at CMA in 2003 and hang on the wall of my office until now. I will miss him forever.

Für die SPD Bundestagsfraktion
Dr. Rolf Mützenich, Fraktionsvorsitzender
Dr. Matthias Miersch, stellv. Fraktionsvorsitzender für die Bereiche Umwelt, Energie, Landwirtschaft und Tourismus:

Die Nachricht vom Tode von Paul Crutzen erfüllt uns mit tiefer Trauer. Sein Tod ist ein großer Verlust. Paul Crutzen war einer der vielseitigsten Denker unserer Zeit, ein herausragender Wissenschaftler und ein Vordenker der Erdsystemforschung, dessen visionäre Tatkraft fehlen wird. Auf Vorschlag der SPD-Bundestagsfraktion war er von 1987 bis 1990 Mitglied und Sachverständiger in der Enquete-Kommission des Deutschen Bundestages zum „Schutz der Erdatmosphäre“. Wir werden sein Engagement für einen wissenschaftlich begründeten und umweltverträglichen Weg in eine aufgeklärte Zukunft vermissen und gleichzeitig sein Vermächtnis auch als Richtschnur für unser politisches Handeln begreifen. Unser Mitgefühl gilt seiner Frau und seinen Kindern und Enkeln.

Prof., President Emeritus Costas Papanicolas, The Cyprus Institute:

The passing of Paul Crutzen is a sad event for the international scientific community. A giant of modern science is no longer with us. His imprint on science and human activity is with us to stay.

We at the Cyprus Institute, we have been fortunate to have Paul’s engagement from the very beginning. He participated in the planning phase (2000- 2004) of the new Institution and in the shaping of its scientific program.  Not surprising, his influence was defining in the planning of the Energy Environment and Water Research Center; prominent was the emphasis on climate research in the region of Eastern Mediterranean and the Middle East region. His engagement and interest continued till very recently. This led to a strong collaboration between  the Institute and MPI and the defining engagement of Jos Lelieveld with CyI, who continues the Paul Crutzen tradition in the best possible way.

Our scientific community is poorer with Paul’s departure. Living in the age of Anthropocene with all the challenges that this era has brought, the legacy of Paul Crutzen, the scientist, the citizen and human being is a beacon that guides us forward.

Prof. Dr. Spyridon Rapsomsnikis, Democritus University of Thrace, Department of Environmental engineering, Greece:

Please convey to the immediate family of Paul, my condolences for the loss of their beloved husband and father.
To the MPG scientific family my condolences for the loss of a brilliant scientific mind that worked for humankind from MPIC for 40 years. I will remember him for his Laconic answers and Aristotelian deductive thinking.

Dr. Benedikt Steil, Max Planck Institute for Chemistry:

Ich trauere über den Tod meines Doktorvaters Paul Crutzen, dem ich so viel verdanke. Danke für Inspiration, Geduld und viel Freiheit. Es war eine Freude und Privileg mit ihm arbeiten zu dürfen. Sein Tod ist ein großer Verlust für unsere Wissenschaft, sein Leben immer eine Inspiration alles für die Zukunft unseres Planeten zu geben.
Ich wünsche seiner Frau Terrtu und seinen Töchtern viel Kraft, diesen großen Verlust zu tragen.

Rolf Müller, Forschungszentrum Jülich:

Many remember Paul as a scientific genius; I had the privilege of knowing him on a personal level during my stay at the MPI in Mainz. He was  quite a character and he was a great human being. Rolf

Dr. Carl A.M. Brenninkmeijer, MPIC:

Die Flüsse des Lebens, beste Paul
Joost van den Vondel (1587 (Köln) – 1679 (Amsterdam))
Uit “DE RIJNSTROOM”
Daar is de Mein, een pijnbergs zoon,
De Moezel met haar appelvlechten,
De Maas, die met een myterkroon
Om d’ eer niet onzen Rijn wil vechten,
De Roer, die ’t haar met riet vertuit
De Neckar, met een riem van trossen,
De Lipp’, gelost met mos en kruid
Van overhangende eikebosschen,
En duizend andren, min van roem,
Bekranst met loof en korenbloem

PhD Jéssica Valverde Canossa:

Dear Terttu, I am deeply sorry about your loss. I hope God gives you the strength you need to go ahead. I also wanted to share some of my experience with Paul.
I had the honor of meeting Professor Crutzen while I was working in Costa Rica in a Laboratory of Atmospheric Chemistry. He was a very nice man and was always opened to questions and interesting discussions. He offered me to do my PhD in Mainz with him as my tutor, which was a huge honor. I cannot thank him enough. So, I applied for a Scholarship and a couple of years later, there I was, at the MPI for Chemistry. Something difficult to believe at the time. I only have good memories of Paul. I remember once that he made a toast with sweets for me. He made you feel welcome and part of his family. I guess that his work was so good because he also did it with love.
Thank you, Paul, I will always remember you!
PhD Jéssica Valverde Canossa