A daily diagnosis of the ionosphere over Brazil is carried out by the Program of Brazilian Space Weather Study and Monitoring (Embrace) of the National Institute for Space Research (Instituto Nacional de Pesquisas Espaciais – Inpe). The variation of plasma (cloud of ions and electrons) in the ionosphere is evaluated by GPS receiver and airglow optical imaging.
Due to the GPS receiver is possible to monitor the TEC (Total Electron Content), while the optical airglow imager generates an image of the light emission of the sky in the ionosphere at 250km high. Both techniques provide two-dimensional information about ionosphere irregularities.
Currently, the mapping of TEC is done every 10 minutes by day, the whole week, and provides a broader view of the events disturbing ionosphere. This monitoring is important because TEC changes the signals received through the ionosphere and interfere in the global positioning system (GPS).
On the other hand, the images are just obtained at night, but show more details on plasma bubbles. Both techniques are complementary and make the ionosphere monitoring more efficient. Embrace program intend to provide this data in real time soon.
The figure above shows the map of South America and the distribution of TEC on November 24, 2011 at 00:50 UT 25/11/11. Shades of green to red show increased plasma density in the South and Southeast, highlighting the location of the equatorial anomaly. The blue shades show a TEC decrease due to the motion of plasma in the equatorial region (source effect) and the rising of plasma bubbles. The picture at right shows the emission observed in São João do Cariri, Paraíba (indicated by a star on the map), covering an area of approximately 1600 km in diameter. The dark band shows the plasma bubbles coinciding with the TEC map. The same effect (presence of plasma bubbles) can be seen in the picture from the imager operated at Cachoeira Paulista (left photo, below). The dark bands in these images coincide with the blue stripe on the TEC map, on the Northeastern Brazil.
Data obtained by Embrace is available on www.inpe.br/climaespacial
Source: INPE
