announced that it will take a leadership role in international efforts to develop integrated, global observing systems.

The Committee on Earth Science and Applications from Space affirms the imperative of a robust Earth observation and research program to address such profound issues as the sustainability of human life on Earth and to provide specific benefits to society. Achieving these benefits further requires that the observation and science program be closely linked to decision support structures that translate knowledge into practical information matched to and cognizant of society’s needs. The tragic aftermath of the 2004 Asian tsunami, which was detected by in situ and space-based sensors that were not coupled to an appropriate warning system in the affected areas of the Indian Ocean, illustrates the consequences of a break in the chain from observations to the practical application of knowledge.

The committee’s vision for the future is clear: The nation needs to rise to the grand challenge of effectively enhancing and applying scientific knowledge of the Earth system both to increase fundamental understanding of our home planet and how it sustains life and to meet increasing societal needs. This vision reflects and supports established national and international objectives, built around the presidential directives that guide the U.S. climate and Earth observing system initiatives. Realizing the vision requires a strong, intellectually driven Earth sciences program and an integrated in situ and space-based observing system—the foundation essential to developing knowledge of Earth, predictions, and warnings—as well as better decision-support tools to transform new knowledge into societal benefits and more effectively link science to applications. The payoff for our nation and for the world is enormous.


The current U.S. civilian Earth observing system centers on the environmental satellites operated by NOAA;1 the atmosphere-, biosphere-, ocean-, ice-, and land-observation satellites of NASA’s Earth Observing System (EOS);2 and the Landsat satellites, which are currently managed under a cooperative arrangement involving NASA and the U.S. Geological Survey (USGS). Today, this system of environmental satellites is at risk of collapse. Although NOAA has plans to modernize and refresh its weather satellites, NASA has no plan to replace its EOS platforms after their nominal 6-year lifetimes end (beginning with the Terra satellite in 2005), and it has canceled, descoped, or delayed at least six planned missions, including the Landsat Data Continuity “bridge” mission.3

These decisions appear to be driven by a major shift in priorities at a time when NASA is moving to implement a new vision for space exploration. This change in priorities jeopardizes NASA’s ability to fulfill


See discussion at the NOAA Web site at <>.


EOS is composed of a series of satellites, a science component, and a data system supporting a coordinated series of polar-orbiting and low-inclination satellites for long-term global observations of the land surface, biosphere, solid Earth, atmosphere, and oceans. See “The Earth Observing System,” at <>.


In accordance with congressional guidance and the Land Remote Sensing Policy Act of 1992 (PL 102-555), the Commercial Space Act of 1998 (PL 105-303), and the U.S. Commercial Remote Sensing Policy (April 25, 2003), NASA and the Department of the Interior/USGS initially planned to continue the Landsat-7 data series by implementing a Landsat Data Continuity Mission (LDCM) that would procure data from a privately owned and commercially operated remote sensing system. Following an evaluation of proposals, NASA declined to accept any offers and canceled this plan in September 2003. Per guidance from the White House Office of Science and Technology Policy, NASA then agreed to transition Landsat measurements to an operational environment through the incorporation of Landsat-type sensors on the National Polar-orbiting Operational Environmental Satellite System (NPOESS) platform. NASA also agreed to further assess options to mitigate the risks to data continuity prior to the first NPOESS-Landsat mission, including a “bridge” mission. Unless otherwise specified, the committee’s reference to cancellation of the LDCM is to this bridge or “gap filler” option, which would have launched a free-flying instrument to avoid a gap in data continuity between the already-degraded Landsat 7 and the launch of the first NPOESS-Landsat satellite in late 2009 or early 2010.

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