But experts warn the high-tech network of sensors and buoys would be useless unless countries like Indonesia beef up communications links to the coastal communities that would be hit by giant waves.
Many coastal villages that bore the brunt of last month's earthquake and tsunami lack modern communication networks. Many don't even have telephones.
An Indian Ocean tsunami warning system is expected to dominate Thursday's gathering of leaders from stricken nations and world donors following the Dec. 26 earthquake and tsunami that killed an estimated 150,000 people.
"There's no point in spending all the money on a fancy monitoring and a fancy analysis system unless we can make certain that the infrastructure for the broadcast system is there," said Phil McFadden, chief scientist at Geoscience Australia, which has been tasked with designing an Indian Ocean system by the Australian government.
"That's going to require a lot of work," he said. "If it's a tsunami, you've got to get it down to the last Joe on the beach. This is the stuff that is really very hard."
Asian leaders including Japanese Prime Minister Junichiro Koizumi - whose nation's $500 million pledge makes it the biggest contributor so far - are to attend Thursday's summit, along with U.S. Secretary of State Colin Powell, U.N. Secretary-General Kofi Annan and top European Union officials.
At a joint news conference Tuesday in Bangkok with U.S. Secretary of State Colin Powell - visiting to assess tsunami relief needs - the Thai government said it would welcome U.S. technical assistance for an early warning system for tsunamis in the Indian Ocean and South China Sea.
A tsunami warning system already links 26 Pacific Ocean nations. If it had been expanded to the Indian Ocean coastal countries, the National Oceanic and Atmospheric Administration might have been able to warn them, the agency's chief, Conrad C. Lautenbacher, said last week.
Over the years, the United Nations and other agencies that track tsunamis have endorsed establishing such a system for the Indian Ocean.
But the countries that suffered the highest death tolls, like Indonesia and Sri Lanka, say they lack the funds to finance such a system.
Among the dozen nations affected by the Dec. 26 earthquake and tsunami, only Indonesia received any warning from NOAA, and then only indirectly through Australia. Officials from the Pacific Ocean warning system put out an advisory to their members and attempted unsuccessfully to contact countries in the path of the tsunami.
Thailand and Indonesia are pushing hard for the system. Thai Foreign Minister Surakiart Sathirathai said it would help provide "security for tourists" that are the lifeblood of southern Thailand.
McFadden said a system for the Indian Ocean basin would include 30 seismographs to detect earthquakes. Ten tidal gauges and six special DART (deep ocean assessment and reporting of tsunamis) buoys would also be needed determine whether an earthquake has generated a tsunami, he said.
He estimates that each DART buoy will cost about $250,000 initially, plus annual maintenance costs of up to $50,000.
"My guess at this stage is probably about six DART buoys, which is a fair amount of money," he said. "But this amount of money is nothing compared to the cost of what has happened."
But McFadden's figures do not include the cost of upgrading communications networks in many countries.
Prih Harjadi of the Indonesian Meteorological & Geophysical Agency agrees.
"It's a problem of infrastructure," he said. "We could produce information but we would just send it to local governments. It is up to the authorities there to evacuate the people. Right now, there is nothing."