Satellites played an important role in the global response to the Dec. 26 tsunamis that devastated coastal areas throughout the southern Indian Ocean region and they can play an expanded role in the future — both for disaster response and in some limited cases by providing better warning for those in danger.

As the scope of one of the worst disasters in modern times became apparent, governments and private companies moved quickly to get satellite communications and satellite imagery into the hands of response and rescue authorities .

One real key to the rapid response was the creation in 2000 of an international charter on the coordinated use of space assets in the event of a disaster. The charter members at present include the European, Canadian and French space agencies and their counterparts in Argentina, India, the United States and recent applicant Japan.

The charter was the result of recommendations developed during the UN -sponsored Unispace 3 meeting in July 1999. Since its creation, it has been invoked numerous times and has standing protocols that can be set into motion immediately, as they were Dec. 26 when the Indian Space Research Organisation, the French civil protection service and the UN Office of Outer Space Affairs all notified the other members of the spreading crisis.

Once those calls were received by one of the emergency coordinators who are on duty 24 hours a day, the member nations were able to use their spacecraft and ground assets to help the millions of people affected when a massive earthquake triggered tsunamis that wiped out entire towns.

Satellite imagery has been taken of tens if not hundreds of thousands of square kilometers in Indonesia, Sri Lanka, Thailand and other countries throughout the devastated the region. Emergency officials have been able to compare those images with images taken before the tsunamis, which is vitally important since many areas remain under water.

France and Germany have provided maps based on the satellite imagery and the U.S. National Geospatial Intelligence Agency (NGA) has been using its ClearView contract with commercial satellite companies to give U.S. agencies working with rescuers high-resolution satellite images where objects as small as 1 meter in diameter can be identified. The NGA also has provided information based on data gathered by the United States’ super-secret spy satellites.

In addition to imagery, France provided three Inmarsat mobile communications ground stations to affected areas. This has made it possible for rescue personnel to use live satellite video links to confer with doctors around the world as they struggle to treat thousands of victims.

As significant as the response has been, it could be improved for the future. Additional nations with space assets such as Russia and China should become members of the charter. There also should be expanded availability of satellite communications services from both governments and private companies.

In areas where substantial communications infrastructure has been wiped out, satellites are by far the most reliable — if not the only — link to the outside world. The ability to use satellites for telemedicine can save thousands of lives and otherwise improve treatment. In widespread disasters like the current one, dozens if not hundreds of ground stations are needed, along with satellite telephones to help responders communicate immediately with each other, their home countries and the governments of affected nations.

It also is possible to build satellites capable of providing 24-hour-a-day video of the Earth, which would help weather forecasters track storms and other dangerous weather patterns more closely.

No doubt the next crisis will be a different kind of disaster — cyclones, hurricanes, more earthquakes or perhaps a terrible drought or a devastating war. In any of these cases, satellites can be an important tool for attempting to undo the damage of nature or man. The charter clearly was a great idea for dealing with such crises and it should be expanded.

Satellite services are only a small part of the long list of needs for countries and people affected by natural and man-made disasters. But while satellites cannot replace cash, doctors, engineers, food, relief workers, construction crews and dozens of other pressing needs, they can make the delivery of those services much more efficient.