The team has been systematically monitoring the area by InSAR since 2005 and continues to acquire about six new SAR scenes per month. The thousands of interferograms computed by the team so far have provided a detailed picture of the site and afforded experience in distinguishing real ground deformation from possible artefacts.
The InSAR technique was also applied to data over Mount Nyiragongo to determine whether there were any signs of activity at the volcano.
In order to evaluate the level of risk and increase their knowledge of volcanoes, volcanologists need continuous data over long periods. In some cases, only a satellite is capable of providing this, because some areas are inaccessible or too dangerous to be approached. For instance, to reach Mount Nyamulagira by ground scientists would have to travel through dense tropical forests in a region where rebel forces are present.
Envisat can supply this much-needed information and provide accurate maps of areas at risk. Continuously gathered satellite data can be used to assess risk and detect the slight signs of change that may foretell an eruption.
When an eruption begins, optical and radar instruments can image the various phenomena associated with it, including lava flows, mud slides, ground fissures and earthquakes. Atmospheric sensors can identify the gases and aerosols released by the eruption, and quantify their wider environmental impact.
The GORISK project, funded by the Belgian Science Policy Office and the National Research Fund of Luxembourg, aims to improve and implement techniques dedicated to studying and monitoring the Nyamilagira and Nyiragongo volcanoes through space- and ground-based observations.
SAR images are provided as part of ESA category-1 projects through which the team also ensures the systematic monitoring of other volcanic areas in Cape Verde, Cameroon and Tanzania.
|Contact: Robert Meisner|
European Space Agency