This article originally appeared in the Jan. 29, 2018 issue of SpaceNews magazine.
The Earth, and particularly its climate, is changing. Earth science, therefore, is also changing. And, with those changes, come revisions on not just the missions needed to carry out the science, but how they should be selected.
That is the theme of “Thriving on Our Changing Planet,” the Earth sciences decadal survey released by the National Academies of Science, Engineering and Medicine on Jan. 5. The report, outlining scientific priorities for the next decade and ways to achieve them, is the second such study in the Earth sciences, and reflects lessons from the first one in 2007.
Earth science research, concluded the committee who prepared the report, is more important than ever. “We really look at this information as part of the national infrastructure,” said Waleed Abdalati, director of the Cooperative Institute of Research in Environmental Sciences at University of Colorado and co-chair of the committee. “Earth information from space, whether we realize it or not, has become an integral component of our daily lives.”
That dependence, he said, has grown since the last decadal in 2007. “If you go back 10 or 12 years, we were in a different place when it came to Earth information from space,” he argued during a briefing at the National Academies to unveil the report. He cited the growth of online mapping and weather apps that have become an essential part of daily lives, even if people don’t appreciate that the information comes from space.
This led to what Abdalati called the challenge the decadal survey faced. “This is to pursue ambitious objectives and innovative solutions, because we don’t get to the ambition without the innovation.”
Ambition and innovation
The ambition took the form of the broad range of research that Earth scientists are interested in. Two requests for information early in the development of the report prompted 290 responses. The committee and its supporting panels took those responses and other work to identify 35 key questions and 103 supporting objectives. An example of a key question, he said, is how much sea levels will rise this century, while objectives supporting it might be changes in ice sheets and how much energy is being absorbed by the oceans.
The committee then prioritized those objectives as either most important, very important or important, “because they are, in fact, all important,” Abdalati said. The committee ultimately classified 24 objectives as most important.
In the first Earth science decadal in 2007, a similar effort led to the proposal of a long set of specific missions that could meet the community’s science requirements. However, after a decade, only one of those 15 recommended missions had launched, with two more scheduled for launch this year.
The committee took a somewhat different approach in this report. Abdalati said the committee first mapped those objectives against the “program of record” of missions in operation now or under development. “We identified gaps and recommended ‘targeted observables’: things that we should be looking at,” he said. “That is what led to the recommendations in our report.”
The recommendations include several tiers of missions. At the highest level — similar to flagship-class missions in astrophysics and planetary science — are a proposed set of five “Designated” missions to perform observations considered essential to the overall program.
The report stressed that the committee was not, unlike the 2007 decadal, proposing specific missions. Instead, it offered concepts to study atmospheric aerosols; clouds, convection and precipitation; mass change in ice, snow and oceans; hyperspectral studies of surface biology and geology; and a synthetic aperture radar (SAR) mission to study surface deformation and change.
Nonetheless, the report also included what were in effect notional concepts for spacecraft to perform those studies. The concepts had cost estimates ranging from $300 million for the mass change mission to $800 million for the aerosols and clouds missions. For the most expensive concepts, the committee asked the Aerospace Corporation to perform an independent cost and technical evaluation, similar to what’s been done in other recent decadal surveys for flagship missions.
Abdalati said that, by offering generic concepts for missions rather than more specific ones, it leaves the door open for NASA to decide how to best implement them, including whether to do them in-house — aka “directed” — or not. “Whether they’re competed or directed is really not something we got into,” he said, “but we strongly encourage competition in our recommendations.”
Smaller missions
Competition, and the broader theme of innovation, played a larger role in the smaller classes of missions the decadal included.
The study recommended 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 program a way to take advantage of innovation and competition. “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 effort to encourage innovation is a proposed program the report called “Incubation,” and would provide $20 million a year for instruments, missions or other technologies needed to carry out some high-priority science missions.
“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 address the challenge of maintaining those data sets desired by scientists while staying within limited budgets.
Decision rules
The use of competition, and emphasis on innovation and cost caps, is intended to fit as much science into NASA budget projections that, in the best case, will rise only at the rate of inflation for the next decade. The report included a “sand chart” that showed the missions it included could fit within a budget for NASA Earth science flight programs that grows at the rate of inflation through the 2020s.
The decadal survey does include decision rules on what programs to cut should funding fall short of inflationary growth. Those rules call for initially delaying the largest Designated 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 decision 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 proposed a cut of nearly 10 percent to NASA’s Earth science program for fiscal year 2018, including the termination of several missions and instruments under development. Congress has yet to pass a final 2018 spending bill, with a House version including the Earth science cuts and the Senate version largely restoring them.
“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 offers flexibility should budgets go up instead. “In particular, if you look at the Earth System Explorer category, there are seven worthy observables and only three opportunities for flight,” Gail said. “More resources would mean that you would have four competitions in the decade instead of three.”
The road ahead
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, scheduled for release Feb. 12.
Even before the decadal survey was released, NASA was laying the groundwork for its eventual implementation. Speaking at the Fall Meeting of the American Geophysical Union in December in New Orleans, Michael Freilich, director of NASA’s Earth Science Division, said the delivery of the report would kick off a long “roadmapping” process for turning its recommendations into missions.
That process, he said, will take in inputs from scientists, engineers and the administration “to turn the priorities into actual, executable proto-missions.” That effort, he said will take 12 to 18 months.
There’s no rush because missions in development and operation will consume all of its projected Earth science budget for the next few years. “The budget wedge for new decadal missions doesn’t open up until late 2021 or 2022,” he said.
However NASA implements the decadal survey, it will face the challenge the committee described of obtaining critical Earth science data within constrained budgets. “It’s critical that we understand the behavior of our planet on daily scales and on longer time scales. This is directly tied to our capacity to thrive,” Abdalati said. “The challenge to the community is to find a way to do these things ambitiously, effectively and cost effectively.”
