Preface These Conference Proceedings contain the selected papers of the International Conference «Marchuk Scientific Readings 2020» (MSR-2020) held on October 19 - 23, 2020, in Akademgorodok, Novosibirsk, Russia. The conference is dedicated to the 95th anniversary of the birthday of Academician Guri I. Marchuk. He was the founder and the first Director of the Computer Centre of the Siberian Branch of the USSR Academy of Sciences (currently, the Institute of Computational Mathematics and Mathematical Geophysics SB RAS). In different periods, he was the Chairman of the Siberian Branch of the USSR Academy of Sciences, Chairman of the USSR State Committee for Science and Technology, the last President of the USSR Academy of Sciences, Chairman of the Council of the USSR Academy of Sciences for Space. Hero of Socialist Labour and Lenin Prize winner, Academician Guri I. Marchuk was an outstanding scientist, recognized specialist in computational mathematics and mathematical modelling, nuclear reactor theory, atmospheric physics and geophysics, space, and environmental sciences, medicine, and immunology. He authored more than 350 scientific papers and monographs. Academician Marchuk was a distinguished organizer of science. He created a huge scientific school and was actively working on the introduction of scientific achievements to industry. Guri I. Marchuk made a significant contribution to the development of nuclear reactor technology. He was one of the pioneers of space exploration, the organizer of the international project “World ocean”, international systems for remote sensing of the Earth from space and space station flights to Venus. The purpose of the «Marchuk Scientific Readings» conference series is to gather specialists in numerical analysis, applied mathematics, mathematical modelling, computational technologies, information systems, artificial intelligence, and machine learning to discuss, identify and systematize current results, applications, and promising directions in computational mathematics and computer science. The conference program included 31 plenary, 298 oral, and 46 poster presentations. They were presented in 11 sections and two mini-symposia. The conference sections were: • Numerical solution of differential and integral equations • Computational algebra and approximation methods • Numerical statistical modeling and Monte-Carlo methods • Mathematical geophysics • Mathematical models of atmospheric physics, ocean and environment • Programming • Supercomputer computations • Inverse problems • Informational and computational systems • Machine learning and artificial intelligence methods • Computer biology, medicine and biotechnology Two mini-symposia were held: • Computational geosciences across the scales • Particle-based methods: numerical aspects and modern applications All contributions selected for publication in this volume have been peer-reviewed according to rigorous international standards. We are grateful to the reviewers for maintaining the manuscripts’ standards and quality throughout the reviewing process. However, the authors take full responsibility for the content of their papers. The event was organized by the Institute of Computational Mathematics and Mathematical Geophysics SB RAS and Novosibirsk State University. It was supported by the Russian Foundation for Basic Research (under project 20-01-20025) and the Siberian Branch of the Russian Academy of Sciences. We gratefully acknowledge all our sponsors. Editors Corresponding Member of the RAS Gennady A. Mikhailov Corresponding Member of the RAS Sergey I. Kabanikhin Professor Yurii M. Laevskii Professor Vladimir V. Penenko Professor Boris M. Glinsky Ph.D. Alexey V. Penenko