Where does the Thermospheric Ionospheric GEospheric Research (TIGER) Program go?

• Published in: Advances in space research 2015-10, Vol.56 (8), p.1547-1577
• Main Authors: Schmidtke, G., Avakyan, S.V., Berdermann, J., Bothmer, V., Cessateur, G., Ciraolo, L., Didkovsky, L., Dudok de Wit, T., Eparvier, F.G., Gottwald, A., Haberreiter, M., Hammer, R., Jacobi, Ch, Jakowski, N., Kretzschmar, M., Lilensten, J., Pfeifer, M., Radicella, S.M., Schäfer, R., Schmidt, W., Solomon, S.C., Thuillier, G., Tobiska, W.K., Wieman, S., Woods, T.N.
• Format: Article
• Language: English
• Subjects: Atmospheric and Oceanic Physics; Calibration; Instrumentation; Modeling; Physics; UV/EUV solar spectral irradiance
• ISSN: 0273-1177; 1879-1948
• DOI: 10.1016/j.asr.2015.07.043

At the 10th Thermospheric Ionospheric GEospheric Research (TIGER/COSPAR) symposium held in Moscow in 2014 the achievements from the start of TIGER in 1998 were summarized. During that period, great progress was made in measuring, understanding, and modeling the highly variable UV-Soft X-ray (XUV) solar spectral irradiance (SSI), and its effects on the upper atmosphere. However, after more than 50years of work the radiometric accuracy of SSI observation is still an issue and requires further improvement. Based on the extreme ultraviolet (EUV) data from the SOLAR/SolACES, and SDO/EVE instruments, we present a combined data set for the spectral range from 16.5 to 105.5nm covering a period of 3.5years from 2011 through mid of 2014. This data set is used in ionospheric modeling of the global Total Electron Content (TEC), and in validating EUV SSI modeling. For further investigations the period of 3.5years is being extended to about 12years by including data from SOHO/SEM and TIMED/SEE instruments. Similarly, UV data are used in modeling activities. After summarizing the results, concepts are proposed for future real-time SSI measurements with in-flight calibration as experienced with the ISS SOLAR payload, for the development of a space weather camera for observing and investigating space weather phenomena in real-time, and for providing data sets for SSI and climate modeling. Other planned topics are the investigation of the relationship between solar EUV/UV and visible/near-infrared emissions, the impact of X-rays on the upper atmosphere, the development of solar EUV/UV indices for different applications, and establishing a shared TIGER data system for EUV/UV SSI data distribution and real-time streaming, also taking into account the achievements of the FP7 SOLID (First European SOLar Irradiance Data Exploitation) project. For further progress it is imperative that coordinating activities in this special field of solar–terrestrial relations and solar physics is emphasized.