- About SWE
- Service Domains
- Expert Service Centres
- Other Resources
Transionospheric Radiolink - Monitoring and Forecast of Ionospheric Disturbances
Equivalent Slabthickness at Pruhonice (Czech Republic), provided by Ionosphere Monitoring and Prediction Center (IMPC), DLR.
The service "Transionospheric Radiolink - Monitoring and Forecast of Ionospheric Disturbances" aims to provide an estimate of the occurrence risk of ionospheric disturbances, including monitoring and detection of ionospheric phenomena causing local disturbances of electron density and detection of geomagnetic storms. This service is currently under development. The aim is to consider the following ionospheric phenomena:
- Travelling Ionospheric Disturbances (TIDs),
- depletions and
- D-region absorption.
Currently, this service provides vertical TEC maps, URSI ionospheric parameters and ionospheric perturbation products like the equivalent slab thickness and Rate Of Change of TEC Index (ROTI).
This service is implemented through a combination of products, tools and alerts which can be found through the following tabs along with expert support provided by the teams constituting the SWE Network. Should you require further guidance in the use of this service, or have specific questions about any aspects of the service presented here, don't hesitate to contact the Helpdesk.
The service is implemented through the following set of assets:
This service page is curated by the ESC Ionospheric Weather. For further information, please contact SSCC Help-desk.
While quiet ionospheric conditions are considered in many applications, disturbed conditions limit the functionality and availability of most systems. Prominent ionospheric perturbations are e.g.
- The ionospheric trough: an electron density depletion near the auroral region.
- Ionospheric patches: very localised regions with strong electron density deviations. Patches occur predominantly in the polar regions.
- Travelling Ionospheric Disturbances (TID): TIDs are signatures of atmospheric gravity waves. The atmospheric waves cause perturbations in the winds and density of the thermosphere, which is impacting the electron density.
- Depletions: Electron density depletions in mid-latitudes often occur during high geomagnetic activity. They are related to mid-latitude spread-F plumes (or plasma bubbles).
- D-region absorption: the D-region describes the lower ionosphere at about 80 km altitude. Enhancement of the D-region electron density can cause absorption of high frequency (HF) radio waves used for long-range communication. These D-region electron density enhancements can be primarily attributed to solar flares (X-ray) and radiation storms.
Many radiofrequency applications use models and assumptions of a quiet ionosphere. Sudden or dramatic changes in the electron density impact the functionality of these applications. E.g. ionospheric perturbations can disrupt or modify the radio communication used in aviation, military, emergency applications and by amateur radio operators. The forecasts of ionospheric perturbations can warn many users to take care of a limited functionality of their systems. The monitoring of ionospheric perturbations can be used to provide improved ionospheric corrections for some application.
Equivalent Slab Thickness
The equivalent slab thickness is a measure of the width of the shape of the vertical electron density profile of the ionosphere. The equivalent slab thickness is defined by the ratio of the total electron content (TEC) and the peak electron density of the local ionosphere. To compute the peak electron density, vertical sounding data from the Pruhonice ionosonde stations is used. The corresponding TEC data are extracted from the TEC maps.
The Rate of change of TEC index (ROTI) can be used as a measure to detect disturbances in the ionosphere. We calculate the ROTI from real-time data streams and associate the calculated values to the ionospheric pierce points. ROTI is a good indicator for scintillations.
ROTI maps are provided by IMPC and RTIM. Within the RESOSS application, ROTI at the ground is provided. This product shows ROTI for a specified ground receiver location, which is easier to apply for users.
Current ionospheric conditions
A map of Europe that presents the current level of ionospheric activity, expressed as the deviation of the observed foF2 parameter in respect to the running 30 days median. The colour code (green-orange-red) corresponds to the ionospheric disturbance level (quiet - disturbed - extremely disturbed). The maps are made available with a latency of 15 min in both ASCII and PNG formats.
Solar Flare detectors SISTED and GSFLAI provided by the MONITOR project
Solar flares cause plasma density enhancements in the ionosphere. These immediate electron density perturbations are detected by the following two products:
- The MONITOR product SISTED is monitoring simultaneous sudden enhancements in the ionospheric Total Electron Content (TEC) using the drift rate (second time derivative) of the ionospheric carrier phase product (LI) which can be derived from the GNSS signal. LI is linearly related to the Slant TEC (STEC) along the satellite-receiver ray path under consideration. The drift rate is used to generate a set of three Impact Parameters (IP). An IP tells (in %) how many satellite-receiver pairs are affected by abrupt over ionisation.
- The MONITOR product GSFLAI based on the impact of ionospheric electron content as response to solar flare activity. The ionospheric response appears as a change in Vertical TEC whose time derivative has a linear dependency on the cosine of Solar Zenith Angle. This relationship can be used to create a proxy for the time derivative of Solar EUV flux (in the spectral band of 21-34 nm). Validation studies with direct Solar EUV measurements by the SOHO SEM instrument (X-class flares during the years 2001-2011) have shown that the GSLAI proxy for EUV flux rate is accurate particularly during moderate and strong activity.
For further information, please contact SSCC Help-desk.
The following products are associated with this service:
Ionospheric Disturbances nowcast
- Equivalent slab thickness, Juliusruh
- Equivalent slab thickness, Pruhonice
- GIVE maps (northern Europe)
- ROTI maps (northern Europe)
- ROTI@Ground maps (Fennoscandia)
- Alerts for ionospheric disturbances in the European sector
- Current ionospheric conditions at each ionosonde location.
- ROTI maps for Europe
- ROTI at ground time series (selected locations in northern Europe)
Ionosphere nowcast and forecast
- TEC map (Europe), current
- TEC map (Europe), 1hr forecast
- TEC map (Global), current
- TEC map (Global), 1hr forecast
- VTEC maps (northern Europe)
- Near real-time TEC maps for the European region
- IONMON TEC maps
- TEC and Err(TEC) nowcast modelled maps
- TEC and Err(TEC) 6-hour forecast modelled maps
- TEC and Err(TEC) nowcast modelled values at a given location
- TEC and Err(TEC) 6h forecast modelled values at a given location
- S4 maps (northern Europe)
- σφ maps (northern Europe)
- Local scintillation indices S4 & σφ Kiruna
- Local scintillation indices S4 & σφ Neustrelitz
- Local scintillation indices S4 & σφ Svalbard
- Local scintillation indices S4 & σφ Tenerife
- Local scintillation indices S4 & σφ Toulouse
- S4 and Err(S4) nowcast modelled maps
- SigmaPhi and Err(SigmaPhi) nowcast modelled maps
- S4 and Err(S4) 6-hour forecast modelled maps
- SigmaPhi and Err(SigmaPhi) 6-hour forecast modelled maps
- S4 and Err(S4) nowcast modelled values at a given location
- SigmaPhi and Err(SigmaPhi) nowcast modelled values at a given location
- S4 and Err(S4) 6h forecast modelled values at a given location
- SigmaPhi and Err(SigmaPhi) 6h forecast modelled values at a given location
Solar indices nowcast and forecast
Geomagnetic indices nowcast and forecast
- Magnetogrammes from North(west) Europe and Greenland
- Forecasts of dB/dt
- Real-time and historic geomagnetic activity plots and data files for geomagnetic surveying (total field)
- Real-time and historic geomagnetic activity plots and data files for directional drilling (total field, declination and inclination)
Tools associated with this service:
The AMDA system provides an archive of planetary, solar wind, Earth magnetosphere and ionosphere mission and ground based products. In addition it supports a range of standard models such as magnetic footprints, magnetic fields, solar wind propagation to planets and probes as well as access to external databases of observations and simulations. A key functionality of the system is its embedded plotting, data mining and cataloguing functionalities which are extremely useful in relation to posteriori analysis.
SWE Data is a web application that provides access to a wide range of Space Weather related data sources covering the areas of the spacecraft, ionospheric, and ground effects. SWE Data allows the user to access all data contained in the repository providing analysis and visualisation tools from these disparate sources.
Alerts associated with this service:
This section provides links to web pages or resources that are not part of the SSA Space Weather Network or esa.int domain. These sites are not under ESA control and therefore ESA is not responsible for any of the information or links that you may find there.
Other European Ionosphere Services
- Space Weather Application Service - Ionosphere (SWACI), one of the first prototypes for a near real-time ionosphere data service in Europe, has been established in 2005 by the German Aerospace Center. It is currently transferred into the operational service Ionosphere Monitoring and Prediction Center (IMPC)
- To better classify the ionosphere and forecast its disturbances over Europe, a data collection endeavour called the European Digital Upper Atmosphere Server (DIAS) was initiated in 2004 by a consortium formed around several European ionospheric stations that transmit in real-time ionospheric parameters automatically scaled. The DIAS project is a collaborative venture of eight institutions funded by the European Commission eContent Programme.
- ECSS-E-ST-10-04C Space environment (15 November 2008)