Satellite remote sensing is the primary tool for measuring global changes in the land, ocean, biosphere, and atmosphere. Over the past three decades, active remote sensing technologies have enabled increasingly precise measurements of Earth processes, allowing new science questions to be asked and answered. As this measurement precision increases, so does the need for a precise geodetic infrastructure. Evolving the Geodetic Infrastructure to Meet New Scientific Needs summarizes progress in maintaining and improving the geodetic infrastructure and identifies improvements to meet new science needs that were laid out in the 2018 report Thriving on Our Changing Planet: A Decadal Strategy for Earth Observation from Space. Focusing on sea-level change, the terrestrial water cycle, geological hazards, weather and climate, and ecosystems, this study examines the specific aspects of the geodetic infrastructure that need to be maintained or improved to help answer the science questions being considered.

Satellite remote sensing is the primary tool for measuring global changes in the land, ocean, biosphere, and atmosphere. Over the past three decades, active remote sensing technologies have enabled increasingly precise measurements of Earth processes, allowing new science questions to be asked and answered. As this measurement precision increases, so does the need for a precise geodetic infrastructure. Evolving the Geodetic Infrastructure to Meet New Scientific Needs summarizes progress in maintaining and improving the geodetic infrastructure and identifies improvements to meet new science needs that were laid out in the 2018 report Thriving on Our Changing Planet: A Decadal Strategy for Earth Observation from Space. Focusing on sea-level change, the terrestrial water cycle, geological hazards, weather and climate, and ecosystems, this study examines the specific aspects of the geodetic infrastructure that need to be maintained or improved to help answer the science questions being considered.--Publisher's website.

Geodesy is the science of accurately measuring and understanding three fundamental properties of Earth: its geometric shape, its orientation in space, and its gravity field, as well as the changes of these properties with time. Over the past half century, the United States, in cooperation with international partners, has led the development of geodetic techniques and instrumentation. Geodetic observing systems provide a significant benefit to society in a wide array of military, research, civil, and commercial areas, including sea level change monitoring, autonomous navigation, tighter low flying routes for strategic aircraft, precision agriculture, civil surveying, earthquake monitoring, forest structural mapping and biomass estimation, and improved floodplain mapping. Recognizing the growing reliance of a wide range of scientific and societal endeavors on infrastructure for precise geodesy, and recognizing geodetic infrastructure as a shared national resource, this book provides an independent assessment of the benefits provided by geodetic observations and networks, as well as a plan for the future development and support of the infrastructure needed to meet the demand for increasingly greater precision. Precise Geodetic Infrastructure makes a series of focused recommendations for upgrading and improving specific elements of the infrastructure, for enhancing the role of the United States in international geodetic services, for evaluating the requirements for a geodetic workforce for the coming decades, and for providing national coordination and advocacy for the various agencies and organizations that contribute to the geodetic infrastructure.

Introduction to GNSS Geodesy is a concise reference for beginners and experts in GNSS-based satellite geodesy. It covers all of the important concepts in almost a third of the space of the other GNSS books. Th e book begins with a case study in Augmented Reality to set the stage for what is to come and then moves on to the key elements of GNSS geodesy that make accurate and precise geopositioning possible. For example, it is important to understand the geodetic reference systems and the associated GNSS data processing strategies that enable both accurate and high-precision geopositioning. Chapter 2 gives an overview of GNSS constellations and signals, highlighting important characteristics. Chapter 3 then introduces reference systems in geodesy, covering such topics as time systems, geodetic datums, coordinate systems, coordinate conversions and transformations, and International Terrestrial Reference Frame. Th is lays the framework for the rest of the book. Chapters 4 and 5 dig deep into mathematical formulation of GNSS parameter estimation and observation models. All the concepts are presented clearly and concisely, with diagrams to assist reader comprehension. Chapter 6 describes Continuously Operating Reference Station (CORS) networks and their role in geodesy and definition of reference frames. Various global and regional CORS networks are presented in this section. Th e chapter also covers GNSS data and common formats such as RINEX and RTCM. Chapter 7 introduces the whole cycle of GNSS data processing, including preprocessing, ambiguity fixing, and solution reprocessing methods as commonly used in both epoch solutions and time series data. Th e book concludes with appendices on orbit modelling, GNSS linear combinations, application examples, and an example linear model.

Applying Earth science knowledge to sustainable development, disaster risk reduction, and climate action Data and insights from Earth observations are critical for assessing the health of our planet, monitoring change, and addressing societal challenges from the local to the global scale. Earth Observation Applications and Global Policy Frameworks presents case studies of Earth science information integrated with statistics and socioeconomic data for managing development targets, improving disaster resilience, and mitigating and adapting to climate change. It also showcases open collaboration among researchers, United Nations and government officials, entrepreneurs, and the public. Volume highlights include: Case studies of projects working with local and national governments, and through public-private partnerships, to make the most of the large volume of complex and diverse Earth science information sources Applications from diverse disciplines including wetland preservation, food security, water quality, marine conservation, disasters, urbanization, drought and land degradation, and greenhouse gas monitoring Examples of internationally coordinated initiatives that are driving progress on three landmark United Nations agreements Resources for decision-makers and practitioners in local and national governments The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals.

The advent of highly precise space-based geodetic techniques has led to the application of these techniques to the solution of global earth and ocean problems. Now under consideration is a worldwide network of interconnected fiducial stations where geodetic as well as other scientific measurements can be made. This book discusses the science rationale behind the concept of an extensive global network of fiducial sites. It identifies geophysical problems that cannot be solved without a global approach and cites geodetic objectives that call for a global deployment of fiducial sites. It concludes with operations considerations and proposes a plan for development of the global network.

The Global Geodetic Observing System (GGOS) has been established by the Int- national Association of Geodesy (IAG) in order to integrate the three fundamental areas of geodesy, so as to monitor geodetic parameters and their temporal varia- ?9 tions, in a global reference frame with a target relative accuracy of 10 or b- ter. These areas, often called ‘pillars’, deal with the determination and evolution of (a) the Earth’s geometry (topography, bathymetry, ice surface, sea level), (b) the Earth’s rotation and orientation (polar motion, rotation rate, nutation, etc. ), and (c) the Earth’s gravity eld (gravity, geoid). Therefore, Earth Observation on a global scale is at the heart of GGOS’s activities, which contributes to Global Change - search through the monitoring, as well as the modeling, of dynamic Earth processes such as, for example, mass and angular momentum exchanges, mass transport and ocean circulation, and changes in sea, land and ice surfaces. To achieve such an - bitious goal, GGOS relies on an integrated network of current and future terrestrial, airborne and satellite systems and technologies. These include: various positioning, navigation, remote sensing and dedicated gravity and altimetry satellite missions; global ground networks of VLBI, SLR, DORIS, GNSS and absolute and relative gravity stations; and airborne gravity, mapping and remote sensing systems.