Through this petition, the undersigned want to express their concern regarding the decision of Royal NIOZ to abolish the position of senior scientist Leo Maas, a scientific leader in the field of oceanography.

We have appreciated Leo Maas's work very much. He is brilliant and his contributions are internationally recognized. He is very innovative and his deep knowledge of oceanographic questions, whether they are observational or physical has been, and remains extremely useful to us and many of our colleagues.

Leo Maas served NIOZ and the scientific community for over 30 years. During this period he published approximately one hundred peer-reviewed research papers on oceanographic, fluid-dynamic and mathematical topics. In contrast to the argument that his work is strictly of a theoretical nature, it should be recalled that he contributed about 30 papers discussing ocean observations, part of which were collected by him or through his initiative, using both in situ as well as remote instruments. Together with colleagues, he wrote another 20 papers based on laboratory and numerical modeling, which do not fit the qualification of him operating as a pure theoretical oceanographer. Apart from this fact, it should also be recalled that science very often contains both observational as well as theoretical aspects. Rather than disqualifying theoretical contributions, these should be seen as enriching observational studies by providing an interpretative framework.

Leo Maas also educated a large number of students. Over the 30 year period of his work at NIOZ, he supervised and co-supervised 12 PhD and 50 Master and Bachelor students. In fact, he currently co-supervises two NWO-PhD students who both still have a three years period ahead of them; a period over which they were guaranteed by NWO to receive supervision by Leo Maas. In addition, Leo Maas has been teaching courses at Utrecht University yearly since 2007, some of which, for example his lectures on 'wave attractors' are unique in the world.

Internal gravity waves, Leo Maas' research topic, are in the spotlight of the oceanographic community since a few years and will continue because climate scientists have acknowledged that ultimately only a decent handling of ocean mixing and closed energetics could improve models and simulations. An understanding of the behavior and impact of small-scale internal waves, part of Leo Maas' expertise, will likely be more in demand as global population grows. Understanding the basic physics of the ocean has been, and will remain, essential to determining how the ocean and its resources will fare under shifting climate and human demands.

From this perspective also, it is clearly inopportune to abolish the line of research that Leo Maas has developed. Further, it is our opinion that removing theoretical science is a very poor economic strategy. Theoretical projects coupled to the experimental world offers low-cost route finding to the most productive experimental programs and proves, in the long term to be highly cost efficient.

We therefore urge NIOZ to reopen the position for Leo Maas and propose an agreement that is suitable to an established and internationally recognized scientist.