WASHINGTON — A U.S. National Oceanic and Atmospheric Administration (NOAA) effort to keep a $420 million weather satellite project with Taiwan on track using disaster relief money approved in the wake of Hurricane Sandy has run aground in the U.S. Senate.

Senate Appropriations Committee Chairwoman Barbara Mikulski (D-Md.) and her Republican counterpart, Sen. Richard Shelby of Alabama, rejected NOAA’s proposal to reprogram $13.7 million of the $326 million the agency received under the 2013 Disaster Relief Appropriations Act — also known as the Sandy Supplemental — to cover its share this year of COSMIC-2, a constellation of 12 small satellites designed to observe the bending of GPS signals passing through the atmosphere to obtain highly detailed temperature and humidity soundings.

“[T]he Committee does not approve the request to fund [the] COSMIC-2 satellite system at this time, because it is actually a long-term commitment of $64.7 million not the one-time $13.7 million requested in the plan,” Mikulski and Shelby wrote in a May 7 letter to the top budget official at the U.S. Commerce Department, which oversees NOAA. “Such a long-term satellite request is best proposed through the annual appropriations process and not through an emergency supplemental spend plan. The Committee encourages NOAA to adjust its fiscal year 2014 budget request to incorporate such a request.”

Mikulski’s office did not respond to a request for comment.

A congressional source said appropriators had not ruled out funding NOAA’s COSMIC-2 contribution through some other means, such as allowing NOAA to reprogram some of the $5 billion in 2013 funds Congress approved for the agency in late March. “We’re still looking at it,” the congressional source said May 24. House appropriators, meanwhile, approved NOAA’s Sandy Supplemental spending plan without commenting on COSMIC-2.

NOAA’s 2014 budget request, sent to Congress in April, mentions COSMIC-2 as part of its satellite portfolio but does not seek any money for the program. NOAA spokesman John Leslie declined to answer any questions about COSMIC-2 funding or make anyone available for an interview. Mary Kicza, NOAA assistant administrator for satellite and information services, did not reply to an email seeking comment.

According to program documents and sources who asked to not be identified because they were not authorized to speak on behalf of their organizations, NOAA has committed to paying for an enhanced ground system for COSMIC-2.

Various U.S. government agencies have been funding work on COSMIC-2 since 2010. NASA’s Jet Propulsion Laboratory in Pasadena, Calif., working with Moog Broad Reach, is supplying the core payload: a global navigation receiver dubbed TriG. ITT Exelis, under a contract NASA announced in early May, will provide specialized antennas that will allow the COSMIC- 2 satellites to pick up signals from Europe’s Galileo and Russia’s Glonass global navigation constellations in addition to the U.S. GPS system. A significant part of the U.S. contribution is expected to come from the U.S. Air Force, which is providing space weather sensors for the satellites and paying for their launch. The first six satellites are slated to launch around 2015, along with 15-20 other small satellites, on a demonstration flight of Space Exploration Technologies Corp.’s planned Falcon 9 Heavy rocket.

The initial COSMIC-2 spacecraft are intended to operate in a 520-kilometer-altitude orbit inclined at 24 degrees relative to the equator. The second set of six satellites are to be launched in 2018 into an 800 kilometer orbit inclined at 72 degrees. Sources said launch options for the second batch include flying piggyback on a standard Falcon 9 or going on a Minotaur rocket out of Kodiak Island, Alaska.

Taiwan’s National Space Program Office is supplying the satellites through a contract it awarded in January to Surrey Satellite Technology Ltd. of Britain. A preliminary design review is scheduled for June, according to sources.

The total projected cost of the mission, including operations through 2023, is $420 million, with Taiwan picking up about half the bill, according to program documents and sources. But Taiwan’s support could soon dissolve without a firm U.S. commitment to the full mission, sources said.

The U.S. State Department warned in a January cable from Taipei that U.S. budget uncertainty has put the COSMIC-2 partnership, which it characterized as “the single largest U.S. bilateral cooperation program with Taiwan,” in jeopardy.

“Officials from Taiwan’s National Space Program Office (NSPO) have expressed to us their serious concern that without a funding commitment from the United States, Taiwan’s Legislative Yuan (LY) would likely withdraw funding for Taiwan’s portion of the second launch,” the cable says. “With only the first set of six satellites, the system will fall significantly short of providing the 8000 data points per day identified by scientists as essential to maximizing the accuracy of climate and weather models.”

Taiwan’s National Space Program Office did not respond by press time to a May 29 query about COSMIC-2.

GPS Occultation Data Proving its Value

The concept of using GPS radio occultation data for climate measurements dates back to the late 1980s, but it was not until the mid-1990s that the GPS/MET experiment gave scientists their first taste of what GPS soundings could do for forecasters and researchers alike. Between 2000 and 2002, additional GPS radio occultation receivers were launched as part of Germany’s Champ mission, Argentina’s SAC-C mission and NASA’s Grace mission.

Then in April 2006, six dedicated GPS radio occultation satellites, built by Dulles, Va.-based Orbital Sciences Corp. as part of a collaboration between the Air Force’s Space Test Program and Taiwan’s National Space Program Office, lifted off from Vandenberg Air Force Base, Calif., aboard a Minotaur rocket.

Known as the Constellation Observing System for Meteorology, Ionosphere and Climate, or COSMIC, the mission gave weather forecasters around the globe their first taste of operational GPS radio occultation data. And they liked it.

“It’s been fantastic, I must say,” Jean-Noel Thepaut, head of the data division at the European Centre for Medium-Range Weather Forecasts in Reading, United Kingdom, said in a May 31 telephone interview. “It’s had a very positive impact in our numerical weather forecast. It’s fair to say they are among the three to five most influential instruments in our numerical forecasts.”

Thepaut said the GPS radio occultation receivers flying on a handful of research missions are no substitute for what his center gets from COSMIC-1 and is eager to get from COSMIC-2.

“The research instruments are fine, but we always struggled with the timeliness and reliability,” he said. “If something goes wrong on the weekend we don’t have data until Monday or Tuesday. With COSMIC we have the sort of stability and robustness that’s provided by operational missions.”

Five of the six COSMIC-1 satellites are still in service and are expected to remain operational through 2015.

Thepaut said forecasters currently get no more than 3,000 soundings a day from COSMIC-1 and similar instruments flying on Europe’s MetOp A and MetOp B satellites. COSMIC-2 promises to at least triple the number of temperature and humidity soundings collected on a daily basis.

Thepaut said forecast accuracy would benefit by even more data than COSMIC-2 is designed to provide. “We did some recent studies to simulate radio occultation data to see how much we need before it saturates and doesn’t provide any additional guidance,” he said. “At upwards of 16,000-20,000 a day we are still improving our forecasts. At the moment we are using 3,000 at best.”

An Emerging Commercial Opportunity

Two U.S. companies raising capital to build and launch commercially operated weather satellites equipped with GPS receivers say the global demand for radio occultation data is even greater than what Thepaut says forecasters need to maximize the quality of their predictions.

Tom Yunck, a former NASA researcher who pioneered the GPS receiver flying on the COSMIC-1 satellites, is the founder and chief technology officer of GeoOptics, a Pasadena, Calif.-company aiming to launch a constellation of 24 satellites to collect radio occultation measurements and other data to sell to the world’s weather agencies.

“The user community will soon have a need for more than 50,000 [radio occultation] soundings daily with global distribution,” Yunck said in an email. “COSMIC-2a (the first six satellites) will be in near-equatorial orbits, barely reaching into the U.S. and almost not at all into Europe and northern Asia. It is primarily for space environmental monitoring, not domestic weather forecasting, though it will also be extremely valuable for tropical hurricane forecasting and of course covers Taiwan and much of China, where much of the benefit will fall.

“The second six COSMIC satellites, which will offer global coverage, are not likely to launch before 2018 and will provide a much-needed additional 6,000 soundings per day, though by then the global demand may be for 100,000 or more,” Yunck continued. “This could of course be further delayed so we must push all options. The urgency is NOW! We need any and all new sources of GPS [radio occultation] data as quickly as possible, sources that will be in operation by 2015 and will continue for many decades to come.”

Anne Miglarese, president and chief executive of Bethesda, Md.-based PlanetiQ, agreed that there is robust global demand for GPS radio occultation data and her company — a joint venture between Moog Broad Reach and Millennium Engineering — aims to fill it.

“PlanetiQ believes that vastly more Radio Occultation data will significantly improve the quality of weather forecasts world-wide, will help to establish a much needed global climate record, and will provide data to support operational space weather monitoring and predictions,” Miglarese said in an email. “Recent research out of Europe shows that upward of 50 GPS-RO satellites are needed to realize the maximum impact of the data.”

Brian Berger is editor in chief of SpaceNews.com and the SpaceNews magazine. He joined SpaceNews.com in 1998, spending his first decade with the publication covering NASA. He was named senior staff writer in 2004, a position he held...