Following the massive earthquake and tsunami that hit Japan on 11 March, satellite imagery has been vital in providing a clear picture of the extent of devastation to aid the relief effort now underway.
In response to this event, which turned out to be the biggest earthquake Japan has suffered in living memory, the International Charter 'Space and Major Disasters' was triggered by the Cabinet Office of Japan the same day the earthquake struck.
As a result, satellite images from several space agencies and operators from around the world are being used to map and assess the stricken areas.
Founded 10 years ago, the International Charter is a unique mechanism to ensure that timely satellite images are made freely available to authorities and aid workers coping with the aftermath of a disaster.

By combining Earth observation data from different space agencies, the Charter allows resources and expertise from around the world to be coordinated for rapid response to major disasters.

The value of the initiative lies in the way it has been set up to gather and coordinate a range of different satellite data, turn them into usable products and provide a single access point to the products 24 hours a day, 7 days a week, and at no cost to the user.
Demonstrating the incredible power that Earth can unleash, the devastation caused by the 8.9-magnitude quake has left the world stunned.
Japan's northwestern coastline is thought to have shifted by as much as 4 m to the east and whole towns have been washed away by the tsunami, completely changing the landscape.
Satellite maps are providing essential information for search and rescue teams on the ground and for damage assessment. Before-and-after images show how the land has changed and where buildings and roads once stood.

http://www.esa.int/Our_Activities/Observing_the_Earth/Mapping_Japan_s_changed_landscape_from_space

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