SeaWiFS Project


NASA Headquarters, Washington, DC
Goddard Space Flight Center, Greenbelt, MD

September 17, 1998

SEAWIFS COMPLETES A YEAR OF REMARKABLE EARTH OBSERVATIONS

For the first time in history, NASA is releasing dramatic images documenting the Earth's changing biology, both on land and in the oceans, as observed from space for one continuous year.

The changing seasons of life, the "pulse of the planet," are being monitored by the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), which was launched on Aug. 1, 1997, and has continuously produced data since Sept. 18, 1997. The SeaWiFS mission is the first NASA Earth Science data purchase in which industry led the development of the full mission.

"Although originally designed to observe the oceans, SeaWiFS provides a unique capability to study the land and atmospheric processes as well," said Dr. Gene Feldman, oceanographer, who heads SeaWiFS' data processing team at NASA's Goddard Space Flight Center, Greenbelt, MD. "As a result, we can monitor changes in the global biosphere with a single sensor over land and ocean."

Among the highlights of SeaWiFS' first continuous year of observation were new insights into the impact of the El Nio climate anomaly on ocean life. Further, SeaWiFS was able to monitor a variety of natural disasters, including fires in Florida, Mexico, Canada, Indonesia and Russia; floods in China; dust storms in the Sahara and Gobi Deserts; and the progress of hurricanes, such as Bonnie and Danielle.

SeaWiFS enabled scientists to witness the ocean transition from El Nio to La Nia conditions in the Equatorial Pacific, specifically around the Galapagos Island. The instrument also allowed researchers to observe the striking speed with which the ocean returned to its pre-El Nio state. While El Nio essentially shut down the highly productive Equatorial Pacific ecosystem, the subsequent La Nia resulted in unprecedented phytoplankton blooms, which stretched across the entire basin from the South American coast to the Western Pacific warm pool.

Phytoplankton are microscopic marine plants that remove carbon dioxide from the atmosphere for internal use. Scientists are eager to understand this exchange of carbon dioxide and the role it plays in the global climate.

"One of the most fascinating events witnessed in the global ocean was the Spring bloom in the North Atlantic," said Dr. Charles McClain, SeaWiFS project scientist. "While many regions of the ocean experience a spring bloom, the event in the North Atlantic was the most dramatic."

During the winter, storms and surface cooling mix the surface waters of the Atlantic, replenishing the nutrient supply from the deep, cold, nutrient-rich waters. Once sunlight is sufficient to support plant growth, phytoplankton populations explode and persist for nearly three months until nutrients are depleted. This bloom migrates northward following the Sun throughout the spring and summer.

Unexpected phenomena observed by SeaWiFS, according to McClain, were the massive blooms of coccolithophores, a unique type of phytoplankton in the Bering Sea. These blooms may have a significant impact on fish populations in this area, one of the most productive fishery regions in the global ocean.

During the summer-fall of 1997 and spring of 1998, expansive blooms of coccolithophores occurred along the Alaskan shelf. These were the first observations of blooms of this magnitude in the Bering Sea. Coccolithophores shed vast numbers of white carbonate platelets which cloud the water. "The net result was fish that normally spawn in the adjacent rivers could not trasverse the bloom in order to enter the rivers to spawn. In addition, local bird and marine mammal populations had a high mortality rates due to starvation because the fish migrated to other waters," said McClain.

NASA is leading an international collaboration using SeaWiFS data. More than 800 scientists representing 35 countries already have registered to use the data. There are over 50 ground- stations throughout the world which receive data from the spacecraft. In addition, the unique government-industry partnership with ORBIMAGE, Dulles VA, represents a new way of doing business for NASA.

SeaWiFS is an essential component of NASA's Earth Sciences enterprise, an ongoing effort to study the changing global environment. Using the unique perspective available from space, NASA will observe, monitor and assess large-scale environmental processes focusing on climate change.

Remarkable images from this mission are available on the World Wide Web at URL:
http://seawifs.gsfc.nasa.gov/SEAWIFS.html


NASA Headquarters, Washington, DC
Goddard Space Flight Center, Greenbelt, MD

September 23, 1997

FIRST GLOBAL OCEAN-COLOR IMAGES FROM NEW SENSOR SHOW PROMISE FOR CLIMATE, BIOLOGICAL STUDIES

Exciting ocean-color images from the Sea-viewing Wide Field- of-view Sensor (SeaWiFS) -- the first readily available ocean-color data in more than ten years -- should play a major role in studying the ongoing El Nino and in other global warming research.

The SeaWiFS data also is giving scientists their first continuous look at the global biosphere -- the combination of living organisms and their environment. Ocean color is largely determined by the concentration of microscopic marine plants called phytoplankton. Accurately measuring phytoplankton concentration is important to climate change research and to local economic concerns such as commercial fishing.

"The images are more than we ever could have hoped for," said oceanographer Dr. Gene C. Feldman, who heads SeaWiFS's data processing team at the Goddard Space Flight Center, Greenbelt, MD. "Although originally designed to just study the oceans, we've also discovered a way of using it to study the land as well, and as a result, we can study the global biosphere for the very first time."

"The new images clearly show areas of coastal upwelling along the northwest U.S., Argentina and western South Africa. These upwelling events foster dramatic plankton blooms which are a critical source of food for major fisheries. The data will be extremely valuable for fisheries management," said Dr. Charles McClain, SeaWiFS Project Scientist.

SeaWiFS offers great potential for monitoring oceanic conditions that have serious, and often tragic, effects on human health. Coastal blooms of algae have been associated with cholera outbreaks around the world. Early detection of these blooms, and subsequent in-water sampling, may significantly reduce the impact of these outbreaks. Red tides, ocean dumping of organic and chemical waste, and perhaps even oil spills can be tracked with SeaWiFS data, Feldman said.

With SeaWiFS, NASA is leading an international collaboration of researchers. More than 300 scientists representing 35 countries have already registered to use the data. Thirty-eight ground stations spread over 18 countries will receive data from the spacecraft.

NASA also has developed a software package called the SeaWiFS Data Analysis System (SeaDAS) for scientists worldwide to process the data. More than 150 scientists have already been to Goddard to learn how to use this package. Another 79 scientists from 11 countries are signed up for SeaDAS training at the Center this fall.

The SeaWIFS instrument is aboard a commercially built and operated satellite called OrbView 2, owned by Orbital Sciences Corp., Dulles, VA. OrbView 2 was launched at 3 p.m. EDT Aug. 1, 1997, from Vandenberg Air Force Base, CA, aboard an Orbital Pegasus XL launch vehicle. The SeaWiFS mission is unlike many other NASA missions. NASA's SeaWiFS Project described the data they wanted to purchase without giving specific requirements for the spacecraft itself.

"It's a whole new way of doing business," said SeaWiFS Project Manager Dr. Mary Cleave.

The SeaWiFS instrument was built by Hughes/Santa Barbara Remote Sensing, Santa Barbara, CA, and is the only scientific payload on the SeaStar spacecraft, developed by Orbital Sciences Corp. NASA is buying the data and is providing it to researchers throughout the world.

SeaWiFS is a follow-on sensor to the Coastal Zone Color Scanner (CZCS), which operated aboard NASA's Nimbus-7 satellite from 1978-1986 and proved that satellite sensors could detect ocean-color from space. SeaWiFS improves on CZCS by providing global coverage every 48 hours, giving a more accurate determination of phytoplankton concentration.

Images from SeaWiFs are available from the World Wide Web.

The SeaWiFS program supports NASA's Mission to Planet Earth enterprise, a long-term coordinated research effort to study the Earth as a global system and the effects of natural and human- induced changes on the global environment. Using the unique perspective available from space, NASA is observing, monitoring and assessing large-scale environmental processes focusing on climate change.


NASA Headquarters, Washington, DC
Goddard Space Flight Center, Greenbelt, MD

July 29, 1997

LAUNCH OF OCEAN-VIEWING SENSOR SET FOR AUGUST 1

The launch of the Sea-viewing Wide Field-of-View Sensor (SeaWiFS), onboard the Orbital Sciences Corporation (OSC), Dulles, VA, SeaStar spacecraft, is scheduled for Aug. 1, 1997, from Vandenberg Air Force Base, CA. The launch window opens at 4:17 p.m. EDT (1:17 p.m. PDT), with a ten-minute window available.

The SeaWiFS project is part of NASA's Mission to Planet Earth Enterprise, a long-term, coordinated research effort to study the Earth as a global system. Using the unique perspective available from space, NASA is observing, monitoring and assessing large-scale environmental processes, such as the oceans' productivity, focusing on climate change. In line with Mission to Planet Earth's commercial strategy, government-industry partnerships such as SeaStar provide NASA with needed data and may lead to practical commercial data use such as the development of fishing maps and estimation of crop yields for farmers and commodities markets.

"We're looking forward to this upcoming launch," said Dr. Mary Cleave, SeaWiFS Project Manager, at NASA's Goddard Space Flight Center, Greenbelt, MD. "The data from SeaWiFS will be of great benefit to our understanding of global carbon cycling."

Understanding the role of the oceans in the global carbon cycle -- the process by which carbon travels through the Earth's atmosphere, oceans, land and living organisms -- is essential to understanding climate change. Phytoplankton, microscopic marine plants, remove carbon dioxide from the atmosphere for internal use. Scientists are eager to understand this exchange of carbon dioxide and the role it plays in the global climate.

The SeaWiFS instrument will study the carbon cycle by observing the world's oceans from space and measuring "ocean color." The color of most of the worlds oceans varies with the concentration of phytoplankton, which contain chlorophyll, a green pigment. Near coastlines, the color of the ocean is affected by chlorophyll, dissolved organic material and suspended sediments from rivers and lagoons. By observing the color of different parts of the oceans, scientists can measure the amount of these materials in ocean water. "A SeaWiFS launch at this time will be particularly important given what appears to be a very intense El Nino event developing in the equatorial Pacific Ocean," said Dr. Charles McClain, SeaWiFS Project Scientist, of Goddard. "SeaWiFS data will allow us to assess the global impact of the El Nino on marine ecosystems, including coastal waters off the U.S. West Coast."

SeaWiFS represents a new way of doing business for NASA. Rather than building, launching, and controlling a satellite to study an important aspect of the Earth's environment, NASA will purchase commercially available data from a privately built satellite and use the data for environmental research. The SeaWiFS Team has developed, and will operate, a data system that will process, calibrate, validate, archive, and distribute SeaWiFS data for research. All other aspects of the mission -- satellite construction, launch, command and control and tracking -- are the responsibility of OSC. NASA has contracted with OSC to provide, for five years, the raw satellite data which will be used for research purposes. OSC will own the data rights for operational and commercial purposes. OSC has integrated the SeaWiFS instrument, built by Hughes Electronics at the Santa Barbara Remote Sensing, Goleta, CA, into its SeaStar satellite and will market the data for commercial and operational use following launch.

SeaWiFS will be launched from a modified Lockheed L-1011 aircraft aboard an OSC Pegasus XL expendable launch vehicle. The Pegasus XL will be released from the L-1011 at an altitude of 39,000 feet over the Pacific Ocean. Following payload separation, an onboard hydrazine propulsion system will then raise the spacecraft to its final 440-mile (705-kilometer) circular orbit within approximately 20 days after launch.

SeaWiFS can view the world's oceans every two days. Since oceans cover 70 percent of the Earth's surface, SeaWiFS will provide information on a large part of the global biosphere. SeaWiFS also will provide important information for fisheries and coastal zone management. SeaWiFS data, which also are useful for viewing plants on land, can be combined with plant productivity data from other satellites, such as Landsat and other operational weather satellites, to measure the role of the biosphere in the total global carbon exchange.

NASA's Mission to Planet Earth Program Office, located at Goddard, manages the SeaWiFS contract and is developing and will operate the research data system for NASA's Office of Mission to Planet Earth, Washington, DC.

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