10:45 AM - 11:00 AM
[PEM11-10] A Discussion of the Threshold for Issuing Space Weather Advisories at ICAO
Keywords:space weather, aviation, GNSS, ICAO
The International Civil Aviation Organization (ICAO) is establishing Space Weather Global Centers in 2019 to distribute advisories on space weather. Currently, advisories are issued when thresholds are exceeded for information on shortwave communications, satellite positioning, and human exposure.
Discussions on the thresholds are ongoing in the Meteorology Operation Group under the ICAO Meteorology Panel. Currently, fixed values of Moderate 125 and Severe 175 are used for the Total Electron Count (TEC), which is used as an indicator for satellite positioning. On the other hand, TEC varies significantly depending on local time, season, and region, and it is questionable whether fixed threshold values are sufficient.
Currently, NeQuick, Krobucher, and other ionospheric models are used for satellite positioning, and when there is a large discrepancy between these models and the actual ionospheric conditions, the satellite positioning error increases. Therefore, it is better to use the difference between this model and the actual TEC as a new indicator.
Currently, I-scale has been proposed by Nishioka et al. (2017). This is a statistical method to process the TEC at a specific location and use the deviation from the median value as an indicator of ionospheric storms. We applied this indicator and examined the difference from the NeQuick and Krobucher model. In my presentation, I would like to discuss how the domain dependence should be handled and how its impact on the system should be evaluated.
Nishioka, M., T. Tsugawa, H. Jin, and M. Ishii (2017), A new ionospheric storm scale based on TEC andfoF2statistics, Space Weather,15, 228–239, doi:10.1002/2016SW001536.
Discussions on the thresholds are ongoing in the Meteorology Operation Group under the ICAO Meteorology Panel. Currently, fixed values of Moderate 125 and Severe 175 are used for the Total Electron Count (TEC), which is used as an indicator for satellite positioning. On the other hand, TEC varies significantly depending on local time, season, and region, and it is questionable whether fixed threshold values are sufficient.
Currently, NeQuick, Krobucher, and other ionospheric models are used for satellite positioning, and when there is a large discrepancy between these models and the actual ionospheric conditions, the satellite positioning error increases. Therefore, it is better to use the difference between this model and the actual TEC as a new indicator.
Currently, I-scale has been proposed by Nishioka et al. (2017). This is a statistical method to process the TEC at a specific location and use the deviation from the median value as an indicator of ionospheric storms. We applied this indicator and examined the difference from the NeQuick and Krobucher model. In my presentation, I would like to discuss how the domain dependence should be handled and how its impact on the system should be evaluated.
Nishioka, M., T. Tsugawa, H. Jin, and M. Ishii (2017), A new ionospheric storm scale based on TEC andfoF2statistics, Space Weather,15, 228–239, doi:10.1002/2016SW001536.