TomoScand is a collaboration project between Finnish Meteorological Institute and Sodankylä Geophysical Observatory for multi-instrument ionospheric tomography.

TomoScand consists of its own network of low Earth orbit (LEO) satellite receivers, as well as an algorithm for ionospheric tomography. The Jitter GNU Ionospheric Tomography Receivers measure the phase differences in the transmitted 150 and 400 MHz signals caused by the ionosphere. The phase difference is proportional to the electron density along the signal path.

Besides TomoScand network, the method can utilise GNSS measurements provided by National Land Survey of Finland, Geotrim and SWEPOS, as well as incoherent scatter radar and ionosonde measurements provided by EISCAT Scientific Association.

The TomoScand algorithm is based on Bayesian statistical inversion. It combines the information of different measurements and produces a 3D reconstruction for the ionospheric electron density.

TomoScand quicklook data base consists of visualisations of data and automatic tomographic reconstructions for each analysed overflight. The inversions for electron density reconstructions are carried out automatically with general default parameter values and should be used only as rough idea of current ionospheric state. For more detailed conclusions a separate tomographic inversion should be performed with optimised parameters for the specific overflight data.

TomoScand development is currently funded by Academy of Finland (decision no. 287679) and European Regional Development Fund (Regional Council of Lapland, decision no. A70179).

Quicklook figures

Choose a date interval to search for overflights. The first available date is 2014.10.23 and the last available date is 2016.05.15.

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- Hour limiter

Ground-based receivers whose data can be used in the TomoScand inversion.
The measurement setup provided by GNSS and Beacon signals for TomoScand (click for a larger image).