Model reduction and inverse problems and data assimilation with geophysical applications. A special issue in honor of I. Michael Navon's 75th birthday
Professor Ionel Michael Navon retired in September 2014 from the Scientific Computing Department, Florida State University, Tallahassee Florida after a brilliant academic career. Since 1997, he is a fellow of American Meteorological Society and recently he became an honorary member of Academy of Romanian Scientists. His distinguished pioneering achievements in the domains of data assimilation, inverse problems and reduced order modeling during the last few decades have greatly contributed to the establishment and development of these aforementioned fields. In particular, his rich interdisciplinary expertise allowed him to advance the science reduced order modeling and inverse modeling as core techniques for data driven modeling. He generalized predictive computational modeling leading to fast novel solution approaches for real world inverse problems of oceanography and weather forecast. At the same time, Professor Ionel Michael Navon has been an outstanding mentor, advisor, role model and friend to his 9 PhD students and 11 postdoctoral scholars, with the large majority of them pursuing successful academic, scientific, and industry careers. This year Professor Ionel Michael Navon celebrates his 75th anniversary and this special issue recognizes his accomplishments. The contributors to this special issue are former students, postdoctoral scholars, colleagues, close collaborators, and friends of Professor Ionel Michael Navon. The next three paragraphs describe his most important contributions to data assimilation and reduced order modeling fields in the last 10 years while the last part of the editorial focuses on the special issue's contributions. Professor Navon's work addressed fundamental issues in both variational and statistical data assimilation with applications in fluid dynamics and atmospheric flows. Professor Navon extended