Establishing a Reference Network in Parts of Amhara Region, Ethiopia Using Geodetic GPS Equipment Anna Miskas and Andrea Molnar Contact: [email protected] or [email protected] Master’s of Science Thesis in Geodesy No. 3117 TRITA-GIT EX 09-12 Division of Geodesy Royal Institute of Technology (KTH) 100 44 Stockholm, Sweden June 2009 Acknowledgements There is a long list of people from various fields and different backgrounds who contributed both directly and indirectly with their knowledge, experience and simple acts, all being of inestimable significance in accomplishing this project. Sometimes the trivial matters seemed to be the most difficult barriers to overcome therefore we would like to express our gratitude to everybody who had even the smallest contribution to our project. Firstly, we would like to thank Sigrun Santesson, Programme Coordinator for MFS, and Huaan Fan, Director of Studies, who inspired and encouraged us to take the chance to do our thesis work in a developing country. Their advices and ideas on how to start such a project were of high importance. Our warmest thanks go to Lars Palm, a consultant from the Swedish company Orgut Consulting AB, who was our field supervisor. Besides welcoming and introducing us to all our nice colleagues, helping us in every way, he also was a pleasant dinner company and a hero when saving us from a flock of mad dogs. We are very grateful to our supervisor in Sweden, Milan Hormeuz, docent and researcher at the Department of Geodesy, for his technical assistance and the fast and detailed answers through email. We always felt welcome to ask and review our plans that gave us confidence during our work. Thanks to our Professor in Geodesy and examiner, Lars E. Sjöberg, for his advice and opinions during the writing of this thesis. We are grateful for Teshome Taffa, Lecturer and Head of the Department of Land Administration at the Bahir Dar University and Dr. Tadesse Amsalu manager for EPLAUA for inviting us. We are also very thankful for our always helpful colleagues Gebeyehu Belay, Daniel Asmamaw, Birhan Abebe, Shewakena Aytenfisu, Desalegne Tilahun, Yigremew Alemu, Asmare Mekonnen, Habtamu Senshew and all others who showed interest in our project, making everything easier by sharing their knowledge and points of view, it was very appreciated. Thanks for the surveyors whom we shared office with for the nice atmosphere. Special thanks to Daniel for helping us with all kinds of administrative problems, without his help it would have been difficult to solve all practical issues. 3 We were also very fortunate to have such nice drivers: Tadesse, Brhan, Kindu and Ando who were our guides as well, making our trips very joyful. We would also like to thank Erick Asenjo Contreras, Bo-Göran Holmgren and Thomas Dubois who happened to be there in other projects for the good company and for always assisting us with the help we needed in our work. We would also like to mention the small Swedish community for all their help, nice dinners and a memorable Lucia-celebration. Last but not least we would like to express our regards for all the other people who helped us, the kind-hearted and generous people of Ethiopia for their welcoming and helpfulness, they turned every day of our stay into pleasant memories. Photo: Anna Miskas 4 This study has been carried out within the framework of the Minor Field Studies Scholarship Programme, MFS, which is funded by the Swedish International Development Cooperation Agency, Sida. The MFS Scholarship Programme offers Swedish university students an opportunity to carry out two months’ field work, usually the student’s final degree project, in a country in Africa, Asia or Latin America. The results of the work are presented in an MFS report which is also the student’s Master of Science Thesis. Minor Field Studies are primarily conducted within subject areas of importance from a development perspective and in a country where Swedish international cooperation is ongoing. The main purpose of the MFS Programme is to enhance Swedish university students’ knowledge and understanding of these countries and their problems and opportunities. MFS should provide the student with initial experience of conditions in such a country. The overall goals are to widen the Swedish human resources cadre for engagement in international development cooperation as well as to promote scientific exchange between unversities, research institutes and similar authorities as well as NGOs in developing countries and in Sweden. The International Office at KTH, the Royal Institute of Technology, Stockholm, administers the MFS Programme for the faculties of engineering and natural sciences in Sweden. Sigrun Santesson Programme Officer MFS Programme 5 Abstract Since a reform regarding land use became valid in 1975 in Ethiopia, the farmers got long term rights to land owned by the state. In the beginning of the 2000’s a land administration project, Sida - Amhara Rural Development Program, SARDP, was initiated in the Amhara region, with the aim to survey, map and register the land parcels on their holders. This reform resulted in unpredictable difficulties concerning land partitioning and border determination. The problems originated from the fact that the existing reference network, which is a basic condition for determination of location, lacks in availability, precision and number of points. The purpose of this project was to create a reliable, accurate reference system integrated with the existing local reference system, accessible for everyone without any charges. The new established reference network consisting of 12 points was created in east and west Gojam region, in an area with approximately 140 km in east-west direction and 160 km in north-south direction. This master thesis is a description of how this particular reference network was made. It was carried out during 10 weeks as a Minor Field Study in the fall of 2008, in parts of the Amhara region, Ethiopia. For data collection 3 hours long static GPS measurements were performed in four sessions with Leica 1200 receivers. An IGS station and a CORS station located in Addis Ababa and in the town of Jima respectively were used as reference stations in the data processing. To achieve higher accuracy ionospheric correction files and precise satellite orbit data were imported for the processing. The result of the project is presented in both geodetical and Cartesian coordinates, in the frames of IGS05 and ITRF05 in the measurement epoch as well as in the standard epoch of year 2000. The results will also be presented in the national system Adindan UTM37N, which were transformed from IGS05 using a given parameter set from the Ethiopian Mapping Authority, EMA. Keywords: GPS, reference system, Adindan UTM37N, ITRF05, coordinate transformation, Ethiopia, Amhara, EMA, Gojam, static measurement. 6 Preface Already at an early stage of our studies we began considering doing an MFS for our Master of Science Thesis. We began talking with our teachers to find a suitable and interesting project. Through them we got in contact with Lars Palm, a Swedish consultant for Orgut Consulting AB, currently working in the town of Bahir Dar in Ethiopia at the Environmental Protection, Land Administration and Use Authority, EPLAUA. He suggested several possible projects that would be of good use for EPLAUA as well. In the spring of 2008 we got our MFS-grant for the project that took place during September-December in the same year. When arriving to Ethiopia and EPLAUA we got a more detailed description of what they wanted us to accomplish during our stay. The original plan was to create a network that would cover a larger area from the town of Gondar down to the town of Dejen, but because of the circumstances the network was established in a smaller area, with an approximate size of 140 km by 160 km in a part of the Amhara region. Static GPS measurement was the method used when creating the network. This paper will firstly introduce the reader to the background and current situation concerning land administration in the Amhara region. It will also give a brief introduction to the country, in Chapter 1. The following Chapter 2 is a brief literature overview of our main sources to this project. Chapter 3 will provide a short theoretical description of the satellite positioning techniques, focusing on the more documented GPS system. Some theory about the seven parameter Helmert transformation, network adjustment, reference frames and plate tectonics are also mentioned in this chapter. Chapter 4 will cover the most essential part of the work and will deal with the methods required in the work and practical issues that had to be solved in the project. Chapter 5 will treat the data processing both in situ and back in Stockholm. The one done on site was basic, with the aim to just control the collected data. In Stockholm additional data was downloaded to achieve as high accuracy as possible. This chapter also handles the transformation steps with all parameters and links the GPS results to the local datum, Adindan UTM37N. Chapter 6 will deal with the results, the points’ coordinates and their accuracy. General conclusions and suggestions for future use can be found in Chapter 7. If something is unclear for future use of these coordinates please contact us either through EPLAUA or through the following e-mails; [email protected] or [email protected]. 7 Table of contents ACKNOWLEDGEMENTS ..................................................................... 3 ABSTRACT .....................................................................................