• Total Solar Irradiance Sensor (TSIS). A Total Irradiance Monitor (TIM) to measure total solar irradiance was manifested on Glory, and thus was lost as well. In the meantime NASA’s SORCE mission continues to provide TIM data (and spectrally resolved irradiance via the SSI instrument). Launched in January 2003 and currently in its fourth year of extended-phase operations, the spacecraft is powered by batteries that are believed to be the life-limiting factor for the mission.4 NASA thinks that a work-around for a recent spacecraft battery problem could allow SORCE to continue to operate through 2014;5 however, a gap in the TIM record, which extends from 1978, is still likely, absent launch of a free-flyer mission or manifesting of a TIM on another spacecraft that could launch in this time frame. NOAA is examining options for accelerating the flight of TSIS, currently in development at LASP, by flying it as part of the JPSS free-flyer program.6 Unfortunately, because of FY2011 budget limitations, there are currently no identified funds for the flight of TSIS. A broad-band radiometer was also recommended for the decadal survey’s CLARREO mission, but with cost estimates having grown by a factor of 3, NASA has deferred the mission indefinitely.
• OMPS (Ozone Monitoring and Profiling Suite)-Limb. NPP (launched October 28, 2011) is flying both the OMPS Nadir and the OMPS Limb Suite. Unfortunately, JPSS-1 will carry only the OMPS Nadir instrument. Resumption of the flight of the OMPS Limb sensor is planned for JPSS-2, but not until 2019 or later.
• Earth Radiation Budget Sensor (ERBS). CERES (Clouds and the Earth’s Radiant Energy System) sensor FM 5 is also on NPP. CERES FM 6 is planned for flight on JPSS-1 in 2017. ERBS is planned as a CERES follow-on to be flown as part of the JPSS free-flyer program. Unfortunately, as for TSIS, in the FY2011 and FY2012 budgets there are no funds identified for the flight of ERBS.
• Altimeter (ALT). The ocean altimeter instrument, ALT, which had been planned for inclusion on NPOESS (now JPSS), was canceled (“demanifested) in 2006 as a result of the program review and revisions that occurred as part of NPOESS’s “Nunn-McCurdy” certification.7 However, in a bit of a success story, at least through Jason-2, the research-oriented NASA/CNES TOPEX/Poseidon mission has gradually evolved into an international operational program. TOPEX/Poseidon was follow by Jason, which in turn has been followed by the currently operating Ocean Surface Topography Mission (OSTM) on the Jason-2 satellite. Plans are in place by NOAA/EUMETSAT/NASA/CNES to fly Jason-3; however, the possibility of substantial delays is threatening this mission (see Jason-3, below).
• NPOESS to JPSS on the civil side. As already noted, the DOD/NOAA/NASA NPOESS program was canceled in early 2010. What emerged in its place on the civil (NOAA) side was JPSS, a NOAA polar orbiting weather satellite program to be implemented by NASA. NOAA had planned for JPSS-1 to fly in 2014, to be followed by JPSS-2 in 2018; NOAA also assumed that a free-flyer element to JPSS would allow for the flight of key displaced NPOESS climate sensors as discussed above. However, as a result of a continuing resolution that limited FY2011 budgets to those in FY2010, a planned $1.06 billion in FY2011 for JPSS was appropriated at only $382 million. This large funding shortfall appears likely to delay the planned launch of JPSS-1 to at least 2017.
Given the program’s limited funding, the first priority has been to keep NPP on track. Originally planned as a mission to demonstrate all the new NPOESS instrument technologies, companion algorithms, and data-processing approaches, NPP is now being pressed into service as a full-fledged operational element of the new JPSS program to help cope with the extensive delays that had occurred in the NPOESS program
4 See “SORCE Extended Mission Proposal Submitted,” in Solar Radiation and Climate Experiment Monthly Newsletter, February-March 2011, available at http://lasp.colorado.edu/sorce/news/news_letter.htm.
6 As this report went to press, NOAA and the Air Force were examining the possibility of flying a backup TIM from the SORCE program as a hosted payload.
7 Nunn-McCurdy certification is discussed in National Research Council, Ensuring the Climate Record from the NPOESS and GOESR Spacecraft, 2008. For a specific discussion on ALT, see pp. 35-38.