WASHINGTON — While the first of a new generation of polar-orbiting weather satellites remains on schedule to launch next year, the U.S. Government Accountability Office is concerned that it may slip, increasing the risk of a data gap.

In testimony before the House Science Committee’s environment subcommittee July 7, David Powner, director of information technology management issues at the GAO, argued that National Oceanic and Atmospheric Administration had downplayed the risk of a gap that could emerge if an instrument on the Suomi National Polar-orbiting Partnership (NPP) spacecraft fails before the launch of the first Joint Polar Satellite System (JPSS) satellite next year.

Powner criticized NOAA for a chart at a December 2015 hearing that suggested Suomi NPP could last until 2020. NOAA said after that hearing that the extended lifetime is based only the fuel remaining on board the spacecraft, and doesn’t take into account the health of other spacecraft systems.

“It is not the expected life of the spacecraft and its sensors,” he said. “This is just another instance where NOAA’s charts and satellite lifespans have been misleading to the Congress.”

Instead, the key issue is the health of one of the spacecraft’s instruments, the Advanced Technology Microwave Sounder (ATMS). A scan drive motor critical to its operation is showing signs of aging, according to NOAA. “The main concern is the gap with ATMS on NPP, and will it last long enough until we get J-1 up there and transition to the ATMS on J-1,” Powner said, referring to the first JPSS spacecraft. “That’s I think the key question in the near term.”

That first JPSS satellite, also known as JPSS-1, is currently scheduled for launch in March 2017. Powner, though, said he “remained concerned” about that launch date, noting the program had missed several interim milestones and recently delayed the launch readiness date for the spacecraft from December 2016 to January 2017. He said two upcoming key milestones are the delivery of the JPSS ground system, planned for August, and the beginning of thermal vacuum testing of JPSS-1 later this month.

The failure of the ATMS instrument on Suomi NPP before June 2017, the earliest Powner estimated JPSS-1 would be ready to enter service after post-launch checkouts, would deprive scientists of some data from that “early afternoon” polar orbit. That would, in turn, affect the accuracy of weather forecasting.

“There is a marked change in the accuracy in the forecast” over periods of three to seven days if data is no longer available from that orbit, Stephen Volz, assistant administrator for the National Environmental Satellite, Data, and Information Services (NESDIS) at NOAA, said at the hearing.

Powner also warned about the information security of the JPSS ground system. “NOAA has determined that the JPSS ground system is at high risk of compromise” from intruders, he said. NOAA has been working to reduce the number of vulnerabilities in the system, but is still tracking about 1,200 of them. “NOAA needs to close these vulnerabilities much more quickly,” he said.

Despite those issues, Powner said that JPSS was still in better shape than the program it replaced, the National Polar-orbiting Operational Environmental Satellite System (NPOESS), a joint effort of NOAA, NASA and the U.S. Air Force that the Obama Administration cancelled in 2010. “NOAA has done a solid job coming out of the NPOESS debacle and being on the verge of the J-1 launch,” he said.

Rep. Jim Bridenstine (R-Okla.), the chairman of the subcommittee, said he would continue to keep close tabs on the JPSS program as its first satellite approaches launch. “There has been improvement in the JPSS program over the past few years, but there are still potential causes of concern,” he said.

Bridenstine also used the hearing to ask NOAA about the status of its commercial weather data pilot program, which received $3 million in 2016 to purchase GPS radio occultation satellite data from commercial vendors to test its use in NOAA weather models. “The advancements of the commercial weather satellite industry has real potential to improve our forecasting capabilities and provide gap mitigation,” he said.

“It’s going at a relatively breakneck speed,” Volz said of the pilot program. A draft request for quotations is currently being reviewed by industry, he said, with the final request due out in early August. There is no commercial data currently available, he noted, but he said he anticipates the launch of satellites that could provide such data in the next six months.

At a NOAA industry data about the program July 7, Karen St. Germain, director of the NESDIS office of system architecture and advanced planning, said NOAA anticipates awarding one or more contracts by the end of September. The contracts would cover data collected between October 2016 and April 2017.

The pilot program will sidestep one controversial issue about commercial weather. NOAA officials have stated in the past that it would feel obligated to share data it purchased from commercial satellites with other national weather agencies, just as it does with data from its own satellites. That has worried companies who fear losing the ability to sell that data to other customers if NOAA freely shares it.

There are no plans, St. Germain said, to share data purchased under those pilot program contracts with operational partners, but instead only those who will be working to assess the quality of the data. “There are some issues we’re not tackling with the pilot,” she said.