SAN FRANCISCO — Before the fall hurricane season begins in earnest, the U.S. National Oceanic and Atmospheric Administration (NOAA) plans to obtain data on precipitation, atmospheric water vapor and sea surface wind speed from the first satellite in Japan’s new Earth observation constellation.
Through an international data-sharing agreement, NOAA’s National Weather Service will use information drawn from the Advanced Microwave Scanning Radiometer 2 (AMSR-2), launched May 18 on the Japan Aerospace Exploration Agency (JAXA) Global Change Observation Mission-Water satellite, to predict the location, timing and intensity of severe storms, said Mitch Goldberg, NOAA’s Joint Polar Satellite System program scientist.
In July, the new Japanese satellite, known as Shizuku, is scheduled to move into position at the tail end of the A-train, an international constellation of polar-orbiting Earth observation satellites. Approximately three months later, the spacecraft will begin producing operational data on the global water cycle with observation of the atmosphere, clouds, oceans, ice and soil moisture, according to a statement JAXA released May 19. Shizuku will also work in conjunction with other satellites in the NASA-led Global Precipitation Measurement mission, a virtual constellation featuring a U.S.-Japanese core satellite slated to launch in 2014.
NOAA officials, in the meantime, are particularly interested in using Shizuku’s AMSR-2 data since a similar space-based sensor, Shizuku flying on NASA’s Aqua Earth observation satellite, is no longer working, Goldberg said. AMSR-E gathered data for nearly a decade until October, when its microwave antenna stopped spinning “most likely due to aging lubricant in the mechanism,” according to a message posted on NASA’s website.
AMSR-2 also is designed to offer enhanced data-gathering capabilities. For example, the new sensor includes a 2-meter antenna compared with 1.6 meters for its predecessor, to offer improved accuracy including the ability to measure sea surface temperature with a margin of error of less than 0.5 degrees Celsius. Unlike its predecessor, the new sensor also is designed to operate in all weather conditions.
“Traditionally, observations of sea surface temperature, snow cover and sea ice depth could only be observed under clear skies,” Goldberg said. “With AMSR-2, you can derive those products under cloudy conditions as well.”
That feature will enhance NOAA’s ability to spot sea ice in the Arctic region. NOAA currently obtains detailed information on sea ice and snow depth from the Visible Infrared Imaging Radiometer Suite (VIIRS) flying on the NASA-NOAA Suomi National Polar-orbiting Partnership satellite launched in October. VIIRS, however, only works when skies are clear. In some areas of the world, such as Alaska, where land and water often are obscured by clouds, the ability to obtain data in all weather conditions will be extremely helpful, Goldberg said. AMSR-2 data will help NOAA monitor ice in the Northwest Passage and determine when the waterway is clear enough for ships, he added.
The Shizuku data-sharing agreement stems from memorandum of understanding signed in July 2011 by Mary Kicza, NOAA assistant administrator for satellite and information services, and JAXA Executive Director Masanori Homma. According to the agreement, NOAA will operate the AMSR-2 ground station in Svalbard, Norway, assist JAXA in calibrating the instrument and transmit AMSR-2 data from Norway to NOAA and JAXA facilities. In exchange for ongoing access to the AMSR-2 data, NOAA will provide JAXA with data from its Joint Polar Satellite System (JPSS) as well as data products that blend Shizuku and JPSS data.
As part of the Global Change Observation Mission, JAXA plans to launch a series of three satellites to gather information on water-related phenomena and a series of three spacecraft equipped with climate sensors to gather data on clouds, aerosols, vegetation, ocean color, snow and ice. The first Global Change Observation Mission-Climate satellite is scheduled to launch in 2014. The Japanese water and climate satellites are scheduled to offer more than a decade of observations, according to a message posted on the JAXA website by Keizo Nakagawa, Global Change Observation Mission program manager.
JAXA’s plan to continue gathering data on water and climate conditions over many years is one of the reasons NOAA officials are so eager to gain access to the data. “NOAA is interested in sustained observations,” Goldberg said. If an international agency announces plans to launch an Earth observation sensor that will gather data for three or four years with no successor, NOAA officials may study the data to determine its utility but they would be unlikely to invest money making that data available to the NOAA community, he added.
In contrast, NOAA is eager to invest in networks to share data with partners who establish long-term missions, including JAXA and the European Space Agency. The latter, for example, plans to launch a series of Sentinel satellites to gather data for its Global Monitoring for Environment and Security program designed to provide a continuous stream of data extending into the 2030s.
“What we are looking for is more observations, and partnerships with countries provide more observations,” Goldberg said. “As more agencies make commitments to add to the constellation with sustained observations, NOAA is very interested in getting those data sets in real time.”
