03-26-2001

Highlights of the March 30th Science paper

* The annual rate of carbon consumed by the Earth’s land plants and ocean algae fluctuated between 111 billion metric tons during the peak of the 1997-98 El Nino event and 117 billion metric tons during the strong La Nina that followed.

* This result is important for global carbon cycle research because it sets a new baseline measurement for global photosynthesis, the primary pathway through which carbon enters the Earth’s biosphere.

* The SeaWiFS record marks the first time that the abundance of plants and algae have been measured globally by a single instrument, making this the most complete and consistent data set available. Previous estimates of carbon uptake by the biosphere combined sporadic observations over many years from different instruments to produce an annual average.

* The “greenness,” or productivity, of the world’s oceans increased on a global scale during the three years of this study. No such multi-year trend was seen in land plants on a global scale, although certain regions experienced pronounced changes.

* The extent of summer phytoplankton blooms in the Northern Hemisphere exceeded those in the Southern Hemisphere.

Quick Facts about SeaWiFS

* The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) was launched on Aug. 1, 1997, and has continuously collected data since Sept. 18, 1997. The sensor is carried on the OrbView-2 spacecraft, which is operated by Orbital Imaging Corporation (ORBIMAGE) of Dulles, Va.

* The SeaWiFS mission is the first NASA Earth Science “data buy,” and industry/government partnership in which industry led the development of the mission.

* SeaWiFS orbits the Earth from pole to pole 14 times a day providing a complete global view every two days.

* SeaWiFS can pick out features as small as 1 kilometer (.6 miles) across.

* Every month SeaWiFS provides greater global coverage of the biosphere than its predecessor, NASA’s Coastal Zone Color Scanner (CZCS), collected during the entire lifetime of that mission (1978-1986).

* NASA leads an international scientific collaboration using SeaWiFS data. More than 1600 scientists representing 35 countries have registered to use the data. There are over 78 ground stations around the world that receive SeaWiFS data and provide it to NASA.

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