NASA plans to use its share of the new money as a down payment to put what scientists call an aerosol polarimetry sensor in orbit in 2007 to study the composition of greenhouse gases in the atmosphere. Those are the gases that are thought by scientists to contribute to global warming. The sensor will gather its data by measuring light waves as they bounce off aerosols.

The current generation of NASA instruments can measure the quantity of greenhouse gasses in the atmosphere, but yield only limited data about their chemical composition. The advanced polarimeter NASA plans to put in orbit aboard a discarded satellite bus would enable scientists to inventory gasses other than carbon dioxide that are suspected to play a larger role in global warming than previously thought.

The new funding initiative was announced Thursday at the Earth Observation Summit at the U.S. State Department here. Commerce Secretary Don Evans said the funding would be spent on research priorities identified in the Climate Change Science Programs 10-year strategic plan released July 24. That plan, ordered by U.S. President George W. Bush in 2001, called for, among other things, a better understanding of the role non-carbon dioxide gasses play in global warming and carbon sequestration, the trapping of carbon to prevent its release into the atmosphere.

Earth observation, both from space and from sensors on the ground, is critical to understanding and protecting the planet, Evans said.

I dont think there is anything more important than to measure the heartbeat of mother Earth as we move into the 21st Century, Evans said.

Despite an annual worldwide investment of billions of dollars in Earth observation, Evans said, critical gaps persist.

Its time for us to close the data gap that exists out there today and move the Earth observation data system to the next level, he said.

Representatives of more than 30 nations participated in the summit. One of the goals of the participating countries is to lay the ground work for a 10-year plan to establish a closely coordinated international global observation system.

U.S. Secretary of State Colin Powell opened the summit with a call for countries to work together to monitor the Earth and its ecosystems for the mutual benefit of all nations.

The Earth Observation Summit follows a meeting earlier this summer in Evian, France where the G-8 nations called for strengthening international cooperation on global observation as part of a larger science and technology action plan for sustainable economic development. The G-8 is made up of the eight most economically developed nations in the world.

At Thursdays Earth Observation Summit here, the conferees adopted a declaration calling for an international commitment to making such a comprehensive, coordinated observation system a reality within a decade.

The declaration endorses the need to monitor continuously the state of the Earth, to increase the understanding of dynamic Earth processes, to enhance prediction capabilities for changes to the Earth system, and to further implement our environmental treaty obligations. As such, the declaration asserts the need to support a freer exchange of Earth observation data and the development of a 10-year plan for implementing a comprehensive, coordinated, and sustained Earth observation system.

The framework for such a plan is expected to be completed by the time the worlds environmental ministers meet next spring in Tokyo.