GPS and GNSS Technology in Geosciences - Chapter 9: GNSS monitoring natural and anthropogenic phenomena

Over the past several years, there has been a significant development of Global Navigation Satellite System (GNSS). Currently, GNSS systems are used in a variety of applications, including navigation, engineering, and safety-of-life applications, as well as a wide spectrum of scientific applications. Currently, due to the rapid development of Galileo, BeiDou, and QZSS systems and the improvement in positioning techniques in recent years, the number of potential applications will increase. This chapter presents practical research results using GNSS techniques for nonanthropogenic applications such as earthquakes, landslides, and crustal deformations. Various measurement techniques, such as both real-time and postprocess ones and absolute and relative ones, are shown. The only thing that connects all the examples presented in this chapter is their very high accuracy, often at the level of millimeter. As research shows, GNSS can be the base or complement to another measurement technique. GNSS measurements might be integrated together with, for example, classic geodetic measurements, photogrammetry, or interferometric measurements and show the high accuracy and consistency of GNSS solutions with other techniques. At the end of the chapter, challenges related to the use of satellite techniques in future studies related to natural phenomena are presented.