In the framework of the rigorous fusion of GNSS and InSAR observations, the presented work carries out at a straightforward comparison of the wet delay, caused by water vapor, derived from GNSS and InSAR. The contributions of the two sensors to the wet delay are compared in the line of sight towards the SAR satellite. Comparisons of GNSS observations with the satellite-directed InSAR data show that only a partial component of the wet delay remains after the interferogram formation.

Detailed information on the gravitational effect of the Earth's topographic and isostatic masses can be calculated by gravity forward modeling. Within this book, the tesseroid-based Rock-Water-Ice (RWI) approach is developed, which allows a rigorous separate modeling of the Earth's rock, water, and ice masses with variable density values. Besides a discussion and evaluation of the RWI approach, applications in the context of the GOCE satellite mission and height system unification are presented.

This book is the product of five and a half years of research dedicated to the und- standing of radar interferometry, a relatively new space-geodetic technique for m- suring the earth’s topography and its deformation. The main reason for undertaking this work, early 1995, was the fact that this technique proved to be extremely useful for wide-scale, fine-resolution deformation measurements. Especially the interf- ometric products from the ERS-1 satellite provided beautiful first results—several interferometric images appeared as highlights on the cover of journals such as Nature and Science. Accuracies of a few millimeters in the radar line of sight were claimed in semi-continuous image data acquired globally, irrespective of cloud cover or solar illumination. Unfortunately, because of the relative lack of supportive observations at these resolutions and accuracies, validation of the precision and reliability of the results remained an issue of concern. From a geodetic point of view, several survey techniques are commonly available to measure a specific geophysical phenomenon. To make an optimal choice between these techniques it is important to have a uniform and quantitative approach for describing the errors and how these errors propagate to the estimated parameters. In this context, the research described in this book was initiated. It describes issues involved with different types of errors, induced by the sensor, the data processing, satellite positioning accuracy, atmospheric propagation, and scattering character- tics. Nevertheless, as the first item in the subtitle “Data Interpretation and Error Analysis” suggests, data interpretation is not always straightforward.

Atmospheric Water Vapor contains the technical proceedings of the International Workshop on Atmospheric Water Vapor held in Vail, Colorado, on September 11-13, 1979. The papers assess the state-of-the-art in measurement, modeling, and application of atmospheric water vapor properties and highlight important problems that require further effort in order to better understand the atmosphere itself as well as the electromagnetic propagation through the atmosphere. Comprised of 39 chapters, this book begins with a discussion on the optics and spectroscopy of water vapor. Some actual spectra showing the problems specific to the water molecule are described, along with the method used to calculate precise vibration-rotation energy levels and wave functions. Atmospheric infrared transmission measurements in maritime locations are also presented. Subsequent sections explore microwave and millimeter wave phenomena; geoastrophysical applications; and in situ measurements, remote sensing, and meteorology of water vapor. The final chapters deal with the microphysics and atmospheric chemistry of water vapor. This monograph will be of interest to scientists from universities, government agencies, research laboratories, and industry.

We live on a dynamic Earth shaped by both natural processes and the impacts of humans on their environment. It is in our collective interest to observe and understand our planet, and to predict future behavior to the extent possible, in order to effectively manage resources, successfully respond to threats from natural and human-induced environmental change, and capitalize on the opportunities â€" social, economic, security, and more â€" that such knowledge can bring. By continuously monitoring and exploring Earth, developing a deep understanding of its evolving behavior, and characterizing the processes that shape and reshape the environment in which we live, we not only advance knowledge and basic discovery about our planet, but we further develop the foundation upon which benefits to society are built. Thriving on Our Changing Planet presents prioritized science, applications, and observations, along with related strategic and programmatic guidance, to support the U.S. civil space Earth observation program over the coming decade.

Volcanoes and eruptions are dramatic surface man telemetry and processing, and volcano-deformation ifestations of dynamic processes within the Earth, source models over the past three decades. There has mostly but not exclusively localized along the been a virtual explosion of volcano-geodesy studies boundaries of Earth's relentlessly shifting tectonic and in the modeling and interpretation of ground plates. Anyone who has witnessed volcanic activity deformation data. Nonetheless, other than selective, has to be impressed by the variety and complexity of brief summaries in journal articles and general visible eruptive phenomena. Equally complex, works on volcano-monitoring and hazards mitiga however, if not even more so, are the geophysical, tion (e. g. , UNESCO, 1972; Agnew, 1986; Scarpa geochemical, and hydrothermal processes that occur and Tilling, 1996), a modern, comprehensive treat underground - commonly undetectable by the ment of volcano geodesy and its applications was human senses - before, during, and after eruptions. non-existent, until now. Experience at volcanoes worldwide has shown that, In the mid-1990s, when Daniel Dzurisin (DZ to at volcanoes with adequate instrumental monitor friends and colleagues) was serving as the Scientist ing, nearly all eruptions are preceded and accom in-Charge of the USGS Cascades Volcano Observa panied by measurable changes in the physical and tory (CVO), I first learned of his dream to write a (or) chemical state of the volcanic system. While book on volcano geodesy.