Brussels, 4 February 2003
Research at the European Commission's Joint Research Centre (JRC) has revealed the effects of a major earthquake in remote regions of the Indian subcontinent, thus providing vital reference material to analyse other earthquakes in the future. The results of this study will be published today.
Using data provided by the Multi-angle Imaging SpectroRadiometer (MISR) instrument on board the NASA Terra satellite platform, JRC, US, French and German scientists analysed the earthquake that struck the Gujarat province of India, close to the Pakistan border, on 26 January 2001. The study shows that large areas around the epicentre were affected, including regions that could not be visited by survey teams.
"This is key information, especially when considering the humanitarian and economic impacts of such disasters," said European Research Commissioner Philippe Busquin. "Advanced space technology has helped to monitor various surface effects of earthquakes accurately and efficiently. The successful collaboration at EU and international level illustrates the benefits that can be expected from co-ordinated approaches such as under the Global Monitoring for Environment and Security (GMES) initiative. Europe is a major player in space. We are currently building, in co-operation with the European Space Agency and national space agencies, a space policy for the EU so that space-based intelligence can be put at the service of our different policy objectives."
Devastating seismic event
Scientific knowledge gained in the Gujarat survey will help in validating earthquake models and documenting relationships between the magnitude of earthquakes and how far their impact extends.
The 2001 Gujarat earthquake was devastating, with a magnitude of 7.7 on the Richter scale, causing the death of nearly 20,000 people, leaving over 600,000 homeless and affecting 16 million individuals. Many monuments were damaged, as well as agricultural land and infrastructure.
The earthquake also triggered the sudden release of ground water and sediments over large areas, reactivating ancient riverbeds and forming shallow lakes. This 'dewatering' phenomenon included liquefaction a process that causes sediments to behave more like liquids than solids when severe shaking occurs and can lead to severe damage to buildings.
A new way to look at the Earth
This collaborative research uses measurements provided by the MISR instrument on board the NASA Terra satellite launched in December 1999. The unique capability offered by MISR to view the sunlit face of the Earth at nine different angles and at four spectral bands was fully exploited using a new method to detect and monitor the sudden appearance of surface water over a wide region around the earthquake's epicentre.
Such applications were not anticipated when MISR was initially designed. Yet, exploratory research was able to take advantage of the advanced capabilities of the MISR instrument to propose new ways to look at land surface processes on Earth.
Joint JRC-NASA collaboration
The Commission interest in MISR derives from its unique combination of multi-angular and multi-spectral capabilities, allowing extensive analysis of land surfaces and the overlaying atmosphere with pole-to-pole coverage. The Commission has been particularly involved in the exploitation of MISR data to detect and characterise the properties of atmospheric aerosols over land, and to estimate key land surface properties from their spectral and directional signatures.
EU researchers participating in the activities of the MISR Science Team aim to develop original algorithms to provide new information about the status of land surfaces. Together with the NASA team, they have carried out advanced research for the joint retrieval of aerosol and surface properties over land, which is a particularly difficult problem.
EU scientists participating in the project have been awarded the 2001 NASA Group Achievement Award for their contribution to the success of the MISR initiative. The experience gained from being part of the MISR Science Team has led to beneficial feedback for European space agencies and will be further exploited as part of the GMES initiative.
The study will be published today in the American Geophysical Union's journal, "EOS Transactions".
For more information:
DN: IP/03/169 Date: 04/02/2003
DN: IP/03/169 Date: 04/02/2003