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Methods for Assimilating Remotely-Sensed Water Storage Changes Into Hydrological Models

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Methods for Assimilating Remotely-Sensed Water Storage Changes Into Hydrological Models Institut für Geodäsie und Geoinformation Professur für Astronomische, Physikalische und Mathematische Geodäsie Methods for assimilating remotely-sensed water storage changes into hydrological models Inaugural-Dissertation zur Erlangung des akademischen Grades Doktorin der Ingenieurwissenschaften (Dr.-Ing.) der Landwirtschaftlichen Fakultät der Rheinischen Friedrich-Wilhelms-Universität Bonn vorgelegt von Maike Schumacher, M. Sc. aus Frechen Bonn 2016 Referent: Univ. Prof. Dr.-Ing. Jürgen Kusche Korreferent: Univ. Prof. Dr. techn. Wolf-Dieter Schuh Korreferentin: Univ. Prof. Dr. rer. nat. Petra Döll Tag der mündlichen Prüfung: 12.09.2016 Erscheinungsjahr: 2016 Diese Dissertation ist auf dem Hochschulschriftenserver der ULB Bonn http://hss.ulb.uni-bonn.de/diss_online elektronisch publiziert. Angefertigt mit der Genehmigung der Landwirtschaftlichen Fakultät der Universität Bonn. This thesis is dedicated to Matthias Schürheck whose words always enlightened my life and consoled me in difficult times and to Elisabeth Schürheck who is like a shelter for me to find calm and peace. Ein Kinderherz soll sein -- wie die Lilie, so rein, wie der Tau so klar, wie der Spiegel so wahr, wie der Quell so frisch, wie das Vöglein im Gebüsch so froh! --- . “Die Philosophie steht in diesem großen Buch geschrieben, dem Universum, das unserem Blick ständig offen liegt. Aber das Buch ist nicht zu verstehen, wenn man nicht zuvor die Sprache er- lernt und sich mit den Buchstaben vertraut gemacht hat, in de- nen es geschrieben ist. Es ist in der Sprache der Mathematik geschrieben, und deren Buchstaben sind Kreise, Dreiecke und an- dere geometrische Figuren, ohne die es dem Menschen unmöglich ist, ein einziges Wort davon zu verstehen; ohne diese irrt man in einem dunklen Labyrinth herum.” - Galileo Galilei - . Acknowledgments First of all, I would like to thank my supervisor Prof. Dr. Jürgen Kusche who offered me the great chance to undertake my PhD studies in the Astronomical, Physical and Mathematical Geodesy (APMG) group at the Institute of Geodesy and Geoinformation, University of Bonn. I am very grateful for all the fruitful dialogs, the guidance and freedom that gave me the opportunity to build my own research profile, and the valuable insights and suggestions that without doubts helped me to improve the quality of my work. Our dialogs were always very open, and they were forthright with both criticism and praise. My gratitude also goes to Prof. Dr. Wolf-Dieter Schuh (University of Bonn, Germany) and Prof. Dr. Petra Döll (Frankfurt University, Germany) for being a referee of this the- sis, and for providing valuable discussions and kind supports. Prof. Schuh has been my great mathematics teacher, whose understanding of mathematical formulations and pre- cise comments on the parameter estimations considerably improved the quality of my work. I cannot thank enough Prof. Döll for giving me the unique chance to work with the WaterGAP Global Hydrology Model (WGHM) source code, and constantly supporting me to cope with technical-hydrological issues. Without her generous collaboration, the pro- posed calibration and data assimilation framework of this thesis could not be completed. Furthermore, my thanks go to PD Dr. Axel Nothnagel and Prof. Dr. Sven Lautenbach (University of Bonn, Germany) who agreed to be the chairperson and member of my examination board. During my bachelor and master studies, I had great supports from Prof. Kusche, Prof. Schuh, PD Dr. Klaus Börger, Dr. Lutz Roese-Koerner, Dr. Enrico Kurtenbach, Prof. Dr. Torsten Mayer-Gürr (Graz University, Austria), and Dr. Annette Eicker. During this time, I wrote my BSc and MSc theses, and worked as a student assistant in the Theoretical Geodesy (TG) and APMG groups. Their kindness and scientific inputs were essentially the main motivation behind my decision to continue my research towards a PhD. I would like to acknowledge the financial supports awarded by the German Research Foundation (DFG) under the DFG SPP1257 “Mass transport and mass distribution in the Earth system” project “REGHYDRO” and under the “BAYES-G” (Bayesian Methods in Geodetic Earth System Research) project. Further, I am thankful for the exchange grant (2015/16 57044996) awarded by the German Academic Exchange Service (DAAD) to visit the Australian National University (ANU). A great deal of the data that I used in my research was provided mostly freely by inter- national and national organizations such as NASA, ESA, University of Bonn and Graz University. I was also fortunate to receive data sets and great advices on my research, for which particularly, I would like to thank Dr. Matthew Rodell (NASA, USA) for the groundwater well time series in the Mississippi River Basin (USA), Dr. Russell Crosbie (CSIRO, Australia) for the groundwater well observations in the Murray-Darling River Basin (Australia), and Dr. Fabrice Papa (LEGOS-IRD, France) for the Global Inunda- tion Extent from Multi-Satellite (GIEMS) data set. In addition, the river discharge data from the Global Runoff Data Centre (GRDC, Bundesanstalt für Gewässerkunde (BfG), Koblenz, Germany) are acknowledged. I cannot thank Hannes Müller Schmied (Frankfurt University, Germany) enough for taking his time and providing technical and scientific supports regarding the WGHM’s input data, source code modifications, and analysis of the model outputs. His research contribution has had a tremendous positive impact on my experience. The calibration and data assimilation software of this thesis is written using MATLAB and C++ with the Open Source HPS computing libraries ATLAS, BLAS, LAPACK and OpenMPI. I would like to thank Dr. Roelof Rietbrock and Dr. Jan Martin Brockmann (University of Bonn, Germany) for their technical supports, and helping me with various computer issues. My special thanks go to Dr. Ehsan Forootan (Cardiff University, UK), Hannes Müller Schmied, PD Dr. Klaus Börger, Matthieu Talpe (University of Colorado at Boulder, USA), and Sebastian Halsig (University of Bonn, Germany) for proof-reading my thesis. During the last year of my PhD studies, I had the unique chance to spend two months as a guest researcher at ANU, Australia. I am very grateful for the kind supports of Prof. Dr. Albert van Dijk during my research stay at his Water and Landscape Dynamics group at ANU, for sharing his hydrological expertise with me, and the valuable guidance throughout my graduate studies. Thanks to Dr. Paul Tregoning (ANU, Australia), Dr. Luigi Renzullo (CSIRO, Australia), and Dr. Russell Crosbie for the fruitful discussions during my stay in Canberra. I also had a chance to meet Prof. Dr. Jeffrey Walker and Prof. Dr. Valentijn Pauwels at Monash University (Melbourne), Prof. Dr. Shin-Chan Han, Prof. Dr. George Kuczera, and Prof. Dr. Garry Willgoose at the University of Newcastle, Australia, as well as Prof. Dr. Joseph Awange and Prof. Dr. Ir. Peter Teunissen (Curtin University, Australia), whose helpful discussions inspired my work. Especially, I would like to thank Prof. Dr. Mark Thyer (University of Adelaide, Australia) for his invitation to visit the University of Adelaide. This chance gave me the great opportunity to discuss my research with Prof. Dr. Dmitri Kavetski, Prof. Dr. Seth Westra, and Dr. Michael Leonard. I would also like to thank them for their time and scientific supports. My thanks go to the PhD students Siyuan Tian (ANU, Australia), Khandu (Curtin University, Australia), David Wright and Bree Bennett (University of Adelaide, Australia) for their warm welcomes during my visits. In April 2015, I attended a short course on “Model building, inference, and hypothesis testing in hydrology” given by Prof. Dr. Mark Thyer, Prof. Dr. Dmitri Kavetski, Dr. Fabrizio Fenicia (Eawag, Switzerland), and Dr. Benjamin Renard (Irstea, France), which considerably broadened my knowledge about hydrological modeling and inference. This course inspired me to use the simple one-bucket model, discussed in the course, as an example to demonstrate the functionality of the methods in this PhD thesis. During my PhD studies, I attended several national and international conferences. This provided me the great chance to discuss my research with experts in hydrological sciences, geodesy, remote-sensing and statistical analysis. I am very thankful for all the impressions and ideas that I got and that often resulted in new collaborations, naming a few: Prof. Dr. Laurent Longuevergne (University Rennes, France), Dr. Lars Nerger (AWI, Germany), Dr. Rolf Reichle (NASA, USA), Prof. Dr. Gabriëlle De Lannoy (KU Leuven, Belgium), Prof. Dr. Bart Forman (NASA, USA), Andreas Kvas (Graz University, Austria), Dr. Ben Gouweleeuw (GFZ, Germany), Prof. Dr. Thorsten Wagener (Bristol University, UK), Prof. Dr. Andreas Güntner (GFZ, Germany), Prof. Dr. Michael Schmidt (DGFI, Germany), Dr. Guillaume Ramillien (GRGS, France), Dr. Lucia Seoane (GRGS, France), Prof. Dr. Paul Bates (Bristol University, UK), and Dr. Lucia Plank (University of Tasmania, Australia). I would like to thank my colleagues in the TG and APMG group for all the scientific and non-work related discussions, and the wonderful time in a great working environ- ment: Ehsan Forootan, Ina Loth, Klaus Börger, Lutz Roese-Koerner, Cathrin Schnier, Silvia Müller, Annette Eicker, Roelof Rietbrock, Anne Springer, Judith Schall, Laura Jensen, Bernd Uebbing, Ribana Roscher, Jan Martin Brockmann, Boris Kargoll, Anno Löcher, Prof. Dr. Karl-Rudolf Koch, Christina Lück, Christina Esch, Joël Koehler, Michael Plümer, Sandra-Esther Brunnabend, Luciana Fenoglio-Marc, Fan Yang, Gerd
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