G3.2/CR2.4/HS11.7/OS4.9 Spaceborne geodetic sensor observations: From high-frequency geophysical fluid signals to applications in hydro-geodesy, oceanography, and cryospheric sciences (co-organized) |
Convener: Mohammad J. Tourian | Co-Conveners: Roelof Rietbroek , Henryk Dobslaw , Ernst Schrama , Carmen Blackwood , Andreas Güntner , Tonie van Dam , Jean-Paul Boy , Michael Schindelegger |
In the recent past, spaceborne geodetic sensors with a variety of different purposes have established themselves as valuable tools for hydrological, oceanographic, and cryospheric applications. For example, satellite altimetry has demonstrated its potential to act as virtual lake and river gauges. Surface water extent quantification with satellite imagery data allows for the high-resolution monitoring of the geometry of flooded surfaces over large areas. The satellite mission GRACE provides a fundamentally new remote sensing tool for a wide spectrum of Earth science applications by measuring changes in the Earth's gravitational field and thereby mass changes in both oceanic and terrestrial storages. The ubiquity of Global Navigation Satellite Systems (GNSS) additionally provides a wealth of information on several components of the water cycle, including GNSS-based atmospheric sounding for tropospheric water vapour content assessment; GNSS-network deformations reflecting loading effects from hydrological, cryospheric and atmospheric mass changes; and GNSS-reflectometry aiming at the measurement of both changes in water-level heights and local soil moisture.
In addition to signals at weekly to interannual time-scales that are well resolved from repeated space observations, individual sensor recordings are sometimes strongly affected by high-frequency variability caused by, e.g., tides in the solid Earth, oceans and atmosphere and their corresponding crustal deformations that affect permanent station positions; temperature and moisture variability in the troposphere modifying navigation signal dispersion; rapid changes in the amount of terrestrially stored water both in the root zone and in surface water bodies associated with extreme precipitation events and its consequences for the time-variable gravity field; as well as relative changes in regional to global sea-level that are driven by the mass and energy exchange of the global oceans with other components of the Earth system.
This session solicits both contributions that demonstrate new applications of spaceborne geodetic sensors for hydro-geodesy, oceanography, and cryospheric applications, as well as reports about state-of-the-art approaches to observe or model high-frequency variability of geophysical origin, which needs to be treated as accurately as possible during data processing to avoid the misinterpretation of residuals in terms of an entirely unrelated geophysical process.