Ionosphere Monitoring and Prediction Center

One hour Forecast TEC Map, Europe

DLR’s 1 hour forecast TEC maps for Europe provide information about the vertical TEC (VTEC) one hour ahead with a latency of not more than 5 minutes and an update rate of 15 minutes. The maps cover the European region between 30°N – 72°N and 30°W – 50°E with 2° in latitudes and 2° in longitude spatial resolution. The one hour forecast is calculated as a sum of the actual European TEC map and a weighted sum of the temporal TEC gradient of the previous hour and the temporal gradient of the previous day at the same time.

The 1 hour forecast TEC is provided in TEC units (10^16 electrons per square meter) for a shell-height of 400 km.

Every 5 minutes a VTEC matrix with an ionospheric grid point spacing of 2° latitude x 2° longitude is generated and stored in ASCII format. Data is provided here with 15 minutes updated rate. Higher temporal resolution can be provided on request.

This product can be applied to help to improve the accuracy during GNSS positioning. Related validations can be found for instance in Minkwitz et al. (2014). The quality of the 24 hours forecast TEC map is estimated with the deviation between forecast and observation. These errors are monitored through the production pipeline and displayed in a forecast TEC error map. This forecast TEC error map is provided as quality information along with the product.

Product Specification

SpecificationDescription
External partiesGerman Federal Agency for Cartography and Geodesy, data providers below
Data providersEUREF, ASI
Input dataGPS dual-frequency measurements
Input sampling rates1 s
Reliability of data sourceData is preprocessed by DLR including e.g. cycle slip detection
Region of sensorsGlobal - Used stations for TEC map generation are listed in the 
Sensorscf. station list
Single layer shell height400 km
Spatial resolution2° Latitude x 2° Longitude
Boundaries of grid30°N – 72°N, 30°W – 50°E
Temporal resolution15 min
Time informationUTC Time
Reference coordinate systemECEF coordinate system with WGS84 reference ellipsoid
Algorithms2The one hour forecast is calculated as a sum of the actual European TEC map and a weighted sum of the temporal TEC gradient of the previous hour and the temporal gradient of the previous day at the same time.
File formatASCII

ASCII file format

Header line containing: unit of TEC values, UTC time, minimum latitude in degree, maximum latitude in degree, minimum longitude in degree, maximum longitude in degree, latitude step width in degree, longitude step width in degree, size of data matrix

Data matrix with VTEC values in TECU (1e+16 electrons/m²):Upper left corner value represents the minimum longitude and maximum latitude; the lower right corner value represents the maximum longitude and minimum latitude value

Error of the NRT TEC map for Europe, derived from errors of the GNSS measurements.

Terms and Conditions of Use

In any case you plan to use IMPC material please consider the IMPC terms and conditions of use.