WASHINGTON — A report setting priorities for the next decade of Earth science missions recommends that NASA pursue a mix of large and small missions to help better understand the changing nature of the planet.

The report, released by the National Academies of Science, Engineering and Medicine in an event here Jan. 5, includes a portfolio of proposed missions that it believes can fit within NASA’s Earth science budget assuming it grows at the rate of inflation, but with “decision rules” for delaying missions should those budgets fall short.

The proposed missions, along with the existing “program of record” of missions in service today or under development, are intended to help scientists better understand the ways that the climate, water cycle, soil and other resources are changing, research the report argues can be uniquely done with satellites.

“Earth science and applications are a key part of the nation’s information infrastructure, warranting a U.S. program of Earth observations from space that is robust, resilient, and appropriately balanced,” the report states.

That dependence on Earth science data was emphasized at the event. “If you go back 10 or 12 years, we were in a different place when it came to Earth information from space,” said Waleed Abdalati, director of the Cooperative Institute of Research in Environmental Sciences at University of Colorado and co-chair of the committee that developed the report. Society, he argued is now much more dependent on such data. “This really is pervasive in our daily lives.”

The report, he said, embraced the paradigm that such information is critical to daily activities, while figuring out how to effectively collect such information within constrained budgets. “The challenge to the community is to find a way to do these things ambitiously, effectively, and cost effectively,” he said.

Missions large and small

The report proposes a range of missions to continue those observations, augmenting the program of record. At one end is a series of five “Designated” missions to perform observations considered essential to the overall program. Those missions, with costs estimated between $300 and 800 million each, could either be directed missions run by NASA or competed within the scientific community.

The report does not include specific missions for the Designated category, but rather general proposals to study “targeted observables” considered to be of the greatest scientific interest. Those concepts include:

A mission to measure aerosols in the atmosphere using a spacecraft equipped with a backscatter lidar and polarimeter, with an estimated cost of no more than $800 millon;

A mission to study clouds, convection and precipitation using a spacecraft with a dual-band radar, similar to the CloudSat mission, with an estimated cost of no more than $800 million;

A mission to measure mass change in snow, ice and ocean water, similar to the recently-ended GRACE mission and upcoming GRACE Follow-On mission, with an estimated cost of up to $300 million;

A mission with a hyperspectral imager to study surface biology and geology and with an estimated cost of no more than $650 million; and

A mission with a synthetic aperture radar (SAR) that would be a successor to a joint NASA-ISRO SAR spacecraft under development to study surface deformation and change, with an estimated cost of no more than $500 million.

The study also recommends that NASA establish a new line of medium-class Earth science missions, called Earth System Explorer. The program would fly three competitively selected Earth science missions over the decade, each with a $350 million cost cap, that would be limited to studies in one of seven areas, from measurements of greenhouse gases to ocean surface winds and currents.

Abdalati highlighted this proposed Explorer program as one area that would take advantage of innovation and competition to do more for less funding. “We are actually pretty excited about this because it really is an opportunity to push the community into more of what we call ‘NewSpace’: smaller, more agile systems and creative partnerships that will allow much more to be done with the limited resources that are available.”

Another report recommendation is an effort dubbed “Incubation,” and would fund work on instruments, missions or other technologies needed to carry out some high-priority science missions. The report envisions spending $20 million per year on this effort, with the flexibility to use it to take advantage of “unexpected opportunities that occur on sub-decadal scales.”

“It’s a variety of things that allows us to advance to the point where we can do them in a reasonable way in the next decade,” said Bill Gail, chief technology officer at Global Weather Corporation and the other co-chair of the decadal survey committee.

The report also recommended expanding NASA’s existing Venture Class of Earth science missions, which includes standalone spacecraft as well as instruments and suborbital flight opportunities, to include ways to provide continuity for some key observations at a lower cost.

“It’s a challenge to the community to come up with very low cost methods of establishing continuity of observation,” Abdalati said. The goal, he said, is to find ways of maintaining those data sets desired by scientists while staying within limited budgets.

Fitting into constrained budgets

The use of competition and emphasis on innovation and cost caps is intended to fit as much science into budget projections that, in the best case, will rise only at the rate of inflation for the next decade.

“The committee is confident, based on analyses of technical readiness and cost performed during the study, that the recommended observations have feasible implementations that can be accomplished on schedule and within the stated cost caps,” the report stated.

“This is a really exciting opportunity for improving what we do within the research part of the community,” Gail said. That includes, he said, the greater use of commercial data and commercial systems to carry out those observations. “We need to be working aggressively to make that happen.”

The decadal survey does include decision rules on what programs to cut should funding fall short of the inflationary growth projected. Those rules call for initially delaying the largest missions, and then delaying the medium-sized Designated missions and reducing the cadence of Explorer missions if additional cuts are needed.

However, Abdalati said that those decisions rules would break down if Earth science faces “draconian” budget cuts in the coming years, a level that he didn’t specify. The Trump administration did propose a cut of nearly 10 percent to NASA’s Earth science program, including the termination of several missions and instruments under development.

“The decision rules are intended to absorb a modest level of reduction,” he said, such as a flat budget or a slight reduction. For bigger cuts, he said NASA should consult with the National Academies’ Committee on Earth Science and Applications from Space. “There does come a point where the whole thing has to be looked at.”

The report, however, does include flexibility should budgets increase more than expected. “In particular, if you look at the Earth System Explorer category, there are seven worthy observables and only three opportunities for flight,” Gail said. “Because we’ve set that up as a competition, it does scale nicely. More resources would mean that you would have four competitions in the decade instead of three.”

Recommendations for NOAA and USGS

The report went into fewer details about two other agencies with Earth science missions, the National Oceanic and Atmospheric Administration and the U.S. Geological Survey. Both agencies are carrying out their own existing programs of record, which for NOAA include the GOES geostationary orbit and JPSS polar orbit weather satellite programs, and for USGS the Landsat series of spacecraft.

The report did recommend greater collaboration with international partners, citing as one example China, which will be shifting this year at least one of its weather satellites into an early morning polar orbit to complement American and European satellites. “As the world’s largest nation with a robust space program, China… has the potential to fill gaps in our own program,” the report stated, while acknowledging the policy obstacles for such cooperation.

The report also called on NOAA to become a leader among government agencies in the use of commercial data sources, “assessing both their benefits and risks in its observational data portfolio.” NOAA completed a first round of its Commercial Weather Data Pilot program, and plans to start a second round this year.

“We’re early on in understanding how commercial observations get integrated into the operational system or even a research system,” Gail said. “But we see a very positive future for this.”

The report calls on USGS to ensure user needs are met by current and future Landsat spacecraft, while working with NASA to reduce development costs of those satellites. “Both parties need to work hard to bring down future costs of the Landsat system,” Gail said.

Implementation

How the report’s recommendations will be implemented in the coming years is not yet clear. The release of the report is likely too late to influence the fiscal year 2019 budget proposal, set for release as soon as next month. Moreover, the report noted that, even with inflationary growth for NASA’s Earth science budget, money won’t be freed up from current missions to start new ones like those proposed in the report until at least fiscal year 2020.

“The committee recognizes that resource constraints are likely to remain a practical concern during the next decade, and that new resources must be applied wisely when available,” the report stated.

The agencies discussed in the report have yet to comment on the report’s findings, but the report does have the endorsement of University of Oklahoma scientist Berrien Moore, who was co-chair of the previous Earth science decadal survey released in 2007.

“The report is very innovative, particularly in its ability to scale against budgets,” he said at the briefing. “I think that’s extremely powerful.”