GEROS-ISS: Innovative Remote Sensing with Navigation Satellites aboard the International Space Station
Jens, Wickert¹; Beyerle, G.¹; Cardellach, E.²; Förste, C.¹; Gruber, T.³; Helm, A.⁴; Hess, M.P.⁴; Hoeg, P.⁵; Jakowski, N.⁶; Montenbruck, O.⁶; Rius, A.³; Rothacher, M.⁷; Shum, C.K.⁸; Zuffada, C.^9
1German Research Center for Geosciences, GERMANY; ²IEEC/ICE-CSIC, Universitat Autonoma de Barcelona, SPAIN; ³Technical University München, GERMANY; ⁴Astrium GmbH, GERMANY; ⁵Technical University of Denmark, DENMARK; ⁶German Aerospace Center, GERMANY; ⁷ETH Zürich, SWITZERLAND; ⁸Ohio State University, UNITED STATES; ⁹et Propulsion Laboratory

GEROS-ISS (GNSS Reflectometry, Radio Occultation and Scatterometry onboard ISS) is a proposal within the Research Announcement for ISS experiments relevant to study of Global Climate Change, announced by the European Space Agency in late 2011. GEROS-ISS was selected as the only out of 30 submitted proposals for further studies. GEROS-ISS is a new and innovative ISS experiment primarily focussed to exploit reflected signals of opportunity from navigation satellites (L-band) to derive properties of ocean and ice surfaces which are relevant to climate change. Secondary mission goals are S.I. traceable global atmosphere and ionosphere observations using the GNSS radio occultation technique with complementing aspects compared to current satellite missions. GEROS-ISS will pioneer the exploitation of signals from the European Satellite Navigation system Galileo for reflectometry and occultation, thereby improving the accuracy as well as the spatio-temporal resolution of the derived geophysical properties. GEROS-ISS will contribute to the long-term S.I. traceable observation of the variations of major components of the Earth System: Oceans, Cryosphere, Atmo¬sphere/Ionosphere and solid Earth with innovative and complementary aspects compared to current Earth Observation satellite missions. Therefore the data from GEROS-ISS allow for climate change related scientific studies addressing the challenges of ESA’s Earth Observation strategy (SP 1304 The Changing Earth: New scientific challenges for ESA’s living planet). GEROS-ISS will mainly provide mid- and low-latitude observations on sub-mesoscale or longer oceanic variability, surface ocean currents, surface winds, wave heights and the vertical temperature, water vapour and electron density structure for a period of at least 10 years. GEROS-ISS takes advantage of the capacious infrastructure aboard the ISS, which is an unique platform for the development of further and advanced GNSS reflectometry techniques, e.g., to potentially derive additional Earth’s surface parameters critical to understand anthropogenic climate change, as, e.g., soil moisture or mountain glacier elevation change, and other surface parameters. We introduce and review the GEROS-ISS mission idea and the current status of the project.