News and Activities
GGOS IberAtlantic (GGOS IA) functions as a regional node of GGOS, focusing on geodetic activities across the Iberian Peninsula and the Atlantic region. GGOS IA fosters collaboration among geodetic institutions while promoting scientific research and technological development tailored to the region’s unique geophysical characteristics.
New eBook:
GGOS, IAG, 📰 General NewsOne-mm Accuracy Unified Geocentric
Terrestrial Reference System
A new eBook with the title “How to establish and maintain a one-mm accuracy unified Geocentric Terrestrial Reference System – A theoretical model” was now published.
This book contains a set of mathematical models to go from individual raw observations with any space geodetic technique, to the establishment and maintenance of a Geocentric Terrestrial Reference System, GTRS, using decades of observations. The methods proposed here involves a simultaneous and consistent treatment of the GTRS, the Barycentric Celestial Reference System, the Earth orientation parameters, and gravity, 100 % consistent with the goals of the Global Geodetic Observing System, GGOS, and the IERS Conventions. To reach the goal of obtaining a GTRS with one-mm accuracy, the observations much be combined at the single observation level and several model parameters to be estimated must be treated as stochastic processes.
Detailed observation equations are presented and explained for the following techniques: VLBI, SLR, GNSS, DORIS, KBR, and satellite ACCelerometry, ACC. A detailed and consistent observation model covering all the present GNSS-systems is presented. An observation model for near-Earth VLBI observations is also included. Detailed methods for VLBI and GNSS phase ambiguity resolution is presented. Models for the use of colocated clocks and eccentricity vectors between techniques are described. In addition, all model parameters being candidates for inclusion in the solve-for parameter state vector, are identified in detail. Complete state-vectors at the arc-level and global-level are presented. State-of-the-art estimation methods are described in detail with the possibility to use both kinematic and dynamic stochastic parameters. There is a lot attention paid in the text to the modeling parts that will be essential to go from one cm to one mm.
The methods described in the book should be a very good starting point for the production of a new generation of ITRF/GTRS. The procedures leading to the present-day International Terrestrial Reference System, result in errors and inconsistencies between the techniques at a level of almost one order of magnitude higher than the internal precision of any of the techniques. The procedures described in the book, are expected to reduce these inconsistencies with an order of magnitude. “Unified” in the title of this book, means that the models of all types of high-precision space geodetic observations are expected to be consistent within the resulting GTRS to one millimeter. The simultaneous use of the different independent techniques can be considered as a strategy where the “problem” is observed from several “angles”. This strategy will certainly contribute to the de-correlation of the fundamental model parameters of relevance for the realization of the GTRS, BCRS, EOP and gravity.
This is only half of the story of space geodesy. The other equally important part is the availability of globally distributed observations of mm-precision from any of the techniques treated in this book. Only the analysis part is addressed in the text.
For more information how to buy this book, please click here…
One-mm Accuracy Unified Geocentric
Terrestrial Reference System
Mission Earth – Geodynamics and Climate Change Observed Through Satellite Geodesy
GGOS, IAG, 🌍 Geodesy NewsMission Earth – Geodynamics and Climate Change Observed Through Satellite Geodesy
Book Review
Mission Earth
Geodynamics and Climate Change Observed Through Satellite Geodesy
Detlef Angermann, Roland Pail, Florian Seitz and Urs Hugentobler
With interview contributions by Günter Hein, Harald Lesch and Stefan Rahmstorf
Springer-Verlag Berlin Heidelberg, 2022
ISBN 978-3-662-64105-7
ISBN 978-3-662-64106-4 (eBook)
Mission Earth
Such questions are highly relevant for our society – and are answered by geodesy. The central mission of the author’s team led by Dr. Detlef Angermann at the Technical University of Munich is to illustrate and explain precisely this. Thus, proven experts of global geodesy have come together to present their profound knowledge accurately, factually correct and, above all, easily accessible.
To understand the explanations, one does not need a degree in geodesy and certainly not a corresponding specialization. The book is explicitly written “for the curious”. Formulas and derivations – unfortunately very often an argument against an in-depth study of the subject – are not found. Rather, our planet Earth with its complex dynamics is the focus of interest – and with it the current achievements and future possibilities of geodesy to contribute to a better understanding.
The book is divided into a total of five chapters. In a short introduction, the Earth is presented according to the modern view of systems theory as a dynamic planet, which consists of complex, interacting subsystems such as solid Earth, atmosphere, oceans or ice and which is subject to manifold changes. Climate change is already emphasized in the introduction as an example that is particularly visible to society. The chapter closes with the global view of geodesy on the Earth – illustrated by the three “basic pillars”: geometry and kinematics, orientation and rotation, gravitational field. This clarifies the focus of the book and distinguishes it from an overall view of the geodetic portfolio.
Chapter 2 deals with the historical development of geodesy with regard to questions, tasks and methods from the first surveys in antiquity to the age of satellites. This storyline continues in Chapter 3 to describe and explain the approaches, tools, and contributions of global geodesy in the 21st century comprehensively, but – following the objective and the page size – not exhaustively. In Chapter 4, the focus of the considerations is put on the Earth system with the phenomena of global change. This emphasizes that the self-understanding of geodesy is not limited to a rather technological level. Dynamic processes of the solid Earth body, sea level changes or mass displacements in connection with the global water balance due to, e.g., ice melting in the polar region, are treated in detail. Essential statements about these changes, which affect us to a large extent in our everyday lives, are based on the fundamental findings of geodesy.
Already the preceding chapters are excellently written and extremely exciting to read. Finally, this is further enhanced in Chapter 5 by three interviews with renowned experts who are also known to the broader public. The content of this chapter is based on the societal relevance of the highly precise measuring of our planet from space. Prof. G. Hein, who played a key role in shaping the European satellite navigation system Galileo, looks at the importance of navigation systems in modern society. Prof. H. Lesch, known to a wider German audience through his science broadcasts, takes a holistic look at the Earth system. Prof. S. Rahmstorf, one of the lead authors of the Intergovernmental Panel on Climate Change’s Fourth Assessment Report and an advisor to the German government, focuses on climate change and the threats it poses. The book concludes with a summarizing epilogue and a series of recommended readings to deepen and expand the presentations.
With this book, the authors have succeeded in an impressive way in presenting modern geodesy – using the example of global geodesy – in a lively and descriptive manner with regard to its possibilities and achievements and in placing it in the scientific and societal context. They have more than fulfilled their self-formulated claim, especially in times of “fake news”, to “write down what we know for sure because we have measured it directly”. Congratulations!
It is very worthwhile to read the book. Therefore, this book should be widely distributed in our professional community and its neighboring fields, in order to make the relevance and multitude of the geodetic contributions known far beyond science in the narrower sense – and thus to contribute significantly to the awareness and the positive image of geodesy, also supporting the recruitment of young people for our inspiring profession.
Hansjörg Kutterer, Karlsruhe
This book review is an authorized translation of the original German “Buchbesprechung” by Hansjörg Kutterer, published in zfv – Zeitschrift für Geodäsie, Geoinformation und Landmanagement, Heft 2/2021, 146. Jahrgang, Herausgeber: DVW e.V. – Gesellschaft für Geodäsie, Geoinformation und Landmanagement, ISSN 1618-8950. The translation was done with the help of artificial intelligence (machine translation by the service DeepL.com).
Author: H. Kutterer
Book Review – Mission Earth
GGOS, IAG, 📰 General NewsGeodynamics and Climate Change Observed Through Satellite Geodesy
Detlef Angermann, Roland Pail, Florian Seitz and Urs Hugentobler
With interview contributions by Günter Hein, Harald Lesch and Stefan Rahmstorf
Springer-Verlag Berlin Heidelberg, 2022
ISBN 978-3-662-64105-7
ISBN 978-3-662-64106-4 (eBook)
Mission Earth
How does your cell phone know where you are right now? How is our planet changing due to geodynamic processes and ongoing climate change? How can these changes be precisely measured from space? Such questions are highly relevant for our society – and are answered by geodesy. The central mission of the author’s team led by Dr. Detlef Angermann at the Technical University of Munich is to illustrate and explain precisely this. Thus, proven experts of global geodesy have come together to present their profound knowledge accurately, factually correct and, above all, easily accessible.
To understand the explanations, one does not need a degree in geodesy and certainly not a corresponding specialization. The book is explicitly written “for the curious“. Formulas and derivations – unfortunately very often an argument against an in-depth study of the subject – are not found. Rather, our planet Earth with its complex dynamics is the focus of interest – and with it the current achievements and future possibilities of geodesy to contribute to a better understanding.
The book is divided into a total of five chapters. In a short introduction, the Earth is presented according to the modern view of systems theory as a dynamic planet, which consists of complex, interacting subsystems such as solid Earth, atmosphere, oceans or ice and which is subject to manifold changes. Climate change is already emphasized in the introduction as an example that is particularly visible to society. The chapter closes with the global view of geodesy on the Earth – illustrated by the three “basic pillars”: geometry and kinematics, orientation and rotation, gravitational field. This clarifies the focus of the book and distinguishes it from an overall view of the geodetic portfolio.
Chapter 2 deals with the historical development of geodesy with regard to questions, tasks and methods from the first surveys in antiquity to the age of satellites. This storyline continues in Chapter 3 to describe and explain the approaches, tools, and contributions of global geodesy in the 21st century comprehensively, but – following the objective and the page size – not exhaustively. In Chapter 4, the focus of the considerations is put on the Earth system with the phenomena of global change. This emphasizes that the self-understanding of geodesy is not limited to a rather technological level. Dynamic processes of the solid Earth body, sea level changes or mass displacements in connection with the global water balance due to, e.g., ice melting in the polar region, are treated in detail. Essential statements about these changes, which affect us to a large extent in our everyday lives, are based on the fundamental findings of geodesy.
Already the preceding chapters are excellently written and extremely exciting to read. Finally, this is further enhanced in Chapter 5 by three interviews with renowned experts who are also known to the broader public. The content of this chapter is based on the societal relevance of the highly precise measuring of our planet from space. Prof. G. Hein, who played a key role in shaping the European satellite navigation system Galileo, looks at the importance of navigation systems in modern society. Prof. H. Lesch, known to a wider German audience through his science broadcasts, takes a holistic look at the Earth system. Prof. S. Rahmstorf, one of the lead authors of the Intergovernmental Panel on Climate Change’s Fourth Assessment Report and an advisor to the German government, focuses on climate change and the threats it poses. The book concludes with a summarizing epilogue and a series of recommended readings to deepen and expand the presentations.
With this book, the authors have succeeded in an impressive way in presenting modern geodesy – using the example of global geodesy – in a lively and descriptive manner with regard to its possibilities and achievements and in placing it in the scientific and societal context. They have more than fulfilled their self-formulated claim, especially in times of “fake news“, to “write down what we know for sure because we have measured it directly“. Congratulations!
It is very worthwhile to read the book. Therefore, this book should be widely distributed in our professional community and its neighboring fields, in order to make the relevance and multitude of the geodetic contributions known far beyond science in the narrower sense – and thus to contribute significantly to the awareness and the positive image of geodesy, also supporting the recruitment of young people for our inspiring profession.
Hansjörg Kutterer, Karlsruhe
This book review is an authorized translation of the original German “Buchbesprechung” by Hansjörg Kutterer, published in zfv – Zeitschrift für Geodäsie, Geoinformation und Landmanagement, Heft 2/2021, 146. Jahrgang, Herausgeber: DVW e.V. – Gesellschaft für Geodäsie, Geoinformation und Landmanagement, ISSN 1618-8950. The translation was done with the help of artificial intelligence (machine translation by the service DeepL.com).