Bowing
For more than 60 years, NASA’s Earth science missions have advanced our understanding of Earth systems and helped us monitor and manage environmental and climate change impacts such as droughts, deforestation, and flooding from extreme rainfall.
NASA is shifting its approach to prioritize practical applications of its data from the outset in the design, selection, and support of new Earth science missions.
During that time, these missions have typically been designed first and foremost to address the data needs of researchers working to answer pressing scientific questions. Creative applications and uses of these data, such as those aimed at providing practical solutions or improved decisionmaking for societal needs, have often been considered only later in the development and deployment process.
But the increasing urgency of modern environmental challenges demands a more immediate focus on applying insights from Earth-observing missions for the benefit of humankind. NASA is thus shifting its approach to prioritize practical applications of its data from the outset in the design, selection, and support of new missions. As part of this strategy, the agency is also now intentionally building programs and tools with end users in mind and enhancing the societal benefits of existing missions and activities.
Two examples that demonstrate NASA’s updated approach are the Surface Biology and Geology (SBG) mission, which is in development and slated for launch in 2027 or 2028, and the ongoing Ice, Cloud, and Land Elevation Satellite–2 (ICESat-2) mission.
Valuing Applications in Mission Design
An early initiative in this new direction is NASA’s Surface Biology and Geology study, which was the first of several decadal survey science and application targets to be developed.
The 2017 Decadal Survey for Earth Science and Applications from Space articulated a consensus from the research community about the critical importance for mission planners to consider downstream applications of mission data while still addressing the most compelling science questions. Specifically, the survey challenged the Earth science community to “pursue increasingly ambitious objectives and innovative solutions that enhance and accelerate the science/applications value of space-based Earth observations.” Meeting this challenge requires transforming how current missions are implemented, as well as how new missions are designed, to reflect an emphasis on data applications as a measure of data value.
In response, NASA developed its new Earth Science to Action strategy, which was released publicly at the 20 March open session of the National Academies Committee on Earth Science and Applications from Space. This 2024–2034 strategic plan leverages NASA’s unique position as a space and science agency with end-to-end capabilities, from developing and launching innovative technologies to enhancing scientific knowledge and creating tools and models that empower decisionmakers to tackle real-world challenges.
An early initiative in this new direction is NASA’s SBG study, which was the first of several decadal survey science and application targets to be developed. The decadal survey outlined priorities for a future SBG satellite mission, including observing terrestrial vegetation, aquatic ecosystems, snow and ice, active changes in Earth’s surface, and changes in land use, as well as establishing priorities for managing agriculture, natural habitats, water use and quality, and urban development.
The SBG plan integrated these observing needs into a study of potential architectures, which evaluated what kinds of sensors and measurement capabilities are needed to acquire the desired observations. Lee et al. [2022] described how NASA engaged stakeholders in the applications community, including those managing agriculture, coastal and inland aquatic ecosystems, and snow-ice ecosystems, in this architecture study. This engagement provided input into the engineering design of the mission, helped focus discussions with international partners, and reinforced the benefits of clearly defining mission data products early on for both applications and scientific data users.
A subsequent SBG User Needs and Valuation Study also tapped input from a broad set of stakeholders, including the fire response community, those managing the health impacts of urban heat, and conservation and biodiversity managers, among others. In this study, NASA listed applications concepts and decision contexts that could affect the design of SBG architectures. For example, data latency and spatial resolution are two critical factors that often determine whether stakeholder institutions can productively use an observational data set.
Data latency is the total time that elapses between when data are acquired by a sensor and when they become publicly available. If the latency is too long, then the data may not be useful for decisionmaking, for example, to provide communities with timely warnings of flooding during a king tide or to upgrade evacuation warnings from “recommended” to “mandatory.” Similarly, if the spatial resolution of a data set—say, one characterizing flooding or another hazard—is too low, then emergency responders may not be able to locate affected communities to ensure their safety.
However, trade-offs exist among latency, resolution, and mission cost. For example, high-resolution data sets are acquired less frequently than those with lower spatial resolution and therefore are less likely to be available when needed, in part because increasing resolution typically increases mission cost and data latency. Thus, a maximum permissible latency was assigned for every application identified by the SBG user community, such as real-time monitoring and mapping of wildfires, extreme heat in urban environments, and geologic hazards (e.g., volcanic eruptions).
The final architecture selected for the mission includes multiple spacecraft that together will provide data at a 60-meter spatial resolution with less than 24-hour data latency and will include hyperspectral capabilities [Thompson et al., 2022]. In alignment with NASA’s 2024–2034 strategic plan, this final design maximizes both the science priorities identified in the decadal survey and the utility of mission data for all potential applications.
Extending Investments in Existing Missions
A key way that NASA is putting data from existing Earth missions into action is by funding development of innovative new applications and applied research activities.
A key way that NASA is putting data from existing Earth missions into action is by funding development of innovative new applications and applied research activities, for example, through its open Research and Analysis and Earth Action programs. (Earth Action is a new element in NASA’s Earth Science Division and includes the former Applied Sciences portfolio as well as other activities.) A vibrant example of the fruits of this effort is the ICESat-2 mission applications program, which focuses on promoting and socializing the use of this ongoing mission’s data.
ICESat-2 carries a single instrument: the Advanced Topographic Laser Altimeter System, or ATLAS. ATLAS emits laser photons and measures the travel times of return photons reflected back from Earth’s surface to calculate the distance between the spacecraft and the surface. From these observations, the instrument maps surface elevation along spacecraft tracks in high detail with a 45-day latency.
Launched in 2018, ATLAS continues to provide a unique data set, with a structure and sampling density unlike data sets produced by other Earth-observing sensors. And NASA continues to fund applications activities designed to increase the use of ATLAS data to support decisionmaking related to Arctic sea ice, melting land ice, and the status of critical drinking water reservoirs, for example.
The Ice, Cloud, and Land Elevation Satellite–2 applications program has been successful in increasing the visibility of the mission and cementing its enduring value.
The ICESat-2 applications program, which helps users access and apply ATLAS data, has been successful in increasing the visibility of the mission and cementing its enduring value. Volunteer early adopters from the user community, such as marine geospatial data provider TCarta and the Cultural Site Research and Management Foundation, have contributed to developing mission products and activities. And engagement of potential users through meetings, hackweeks, and publications has led to more widespread and clearer understanding of the utility of precise elevation observations from space since the mission’s launch [Brown et al., 2022]. Through its efforts, the applications program is enabling improved integration of applications into future altimetry missions.
Applications for Analyzing Altimetry
ATLAS provides extremely accurate elevation data, but accessing and understanding the data can pose challenges, especially for new users. To facilitate use of the altimetry data and the development of new applications, a suite of tools and products, including the following examples, has been developed.
The icepyx software library has been built by a community of ICESat-2 data users, developers, and scientists. These individuals have collaborated to develop a shared library of existing resources, new code, tutorials, and use cases to enable scientific discovery by simplifying the process of finding, accessing, and analyzing ICESat-2 data sets. The tool is being used, for example, to merge ATLAS ocean height data with ocean buoy observations of temperature, salinity, and depth to accelerate understanding of changes in ocean currents and ice coverage in remote regions [Bisson et al., 2023].
SlideRule is an open framework for on-demand, cloud-based processing of scientific data. The ICESat-2 SlideRule plug-in offers a customizable tool to make use of the mission’s archive of low-level (minimally processed) data products. The user defines a geographic area of interest and key processing parameters, such as aggregation period or product, via an interactive web interface or the application programming interface (API), and SlideRule returns high-level surface elevation point cloud products in seconds to minutes. This functionality enables rapid algorithm development and data visualization and interpretation. SlideRule also facilitates applications that require custom processing of altimetry data, such as measuring interannual variations in snow depth and assessing these variations’ likely impact on water availability in midlatitude mountainous regions [Besso et al., 2024].
The CryoCloud platform provides hackathon-style training workshops, as well as support for scientists to conduct research and teach in a free and accessible online environment.
CryoCloud is a community expert-led cloud environment developing open-source tools for collaborative, open cryospheric research. The platform provides hackathon-style training workshops, as well as support for scientists to conduct research and teach in a free and accessible online environment that is less reliant on local computing resources. For example, CryoCloud is being used in applications to improve understanding of how sea level rise caused by the melting of Greenland’s ice sheet will affect coastal communities.
OpenAltimetry is a free, user-friendly, map-based tool for visualizing surface elevation data collected by the ICESat and ICESat-2 missions. Users define a geographic area, data product, and date of interest via an interactive web interface or API and then can rapidly inspect and download geolocated data. Researchers have used OpenAltimetry to validate tree height measurements collected by the Global Learning and Observations to Benefit the Environment (GLOBE) program [Campbell, 2021] and to investigate surface ice melt in Antarctica as an indicator of warming and ice loss [Geetha Priya et al., 2022].
ICESat-2 QuickLook products accelerate the delivery of a subset of ICESat-2 data from the typical 30–45 days required for highly accurate elevation observations to less than 72 hours. Although QuickLook data come with greater uncertainties in their geolocations and reported heights compared with standard longer-latency data products, their far more rapid availability offers value for applications requiring closer to real-time information. QuickLook data are used in operational systems such as GloLakes, which provides lake levels as inputs for near-real-time monitoring of water resources in more than 27,000 lakes worldwide [Hou et al., 2024]. (Standard data products, once available, replace the QuickLook data files maintained by the National Snow and Ice Data Center to provide the best possible accuracy.)
The Power of Partnerships
SBG and ICESat-2 are just two examples of how NASA is changing its approach to selecting and designing new Earth science missions and extending the usefulness of existing missions. Other examples include upcoming missions such as the Geosynchronous Littoral Imaging and Monitoring Radiometer (GLIMR) and Landsat Next missions, which are slated for launch in 2026–2027 and 2030, respectively.
GLIMR is a geostationary sensor that will be located over the Gulf of Mexico and the southeastern U.S. coastline to provide critical information on harmful algal blooms, oil spills, Sargassum accumulations, and other coastal hazards. The mission was designed with this unique focus to provide critical information for improved responses, containment, and public advisories needed in densely populated regions. Landsat Next, a constellation of three identical observatories, has been redesigned to respond to the needs of the extensive Landsat user base by providing more frequent observations and higher spatial resolution while continuing Landsat’s legacy through sustainable mission operations.
What isn’t changing in NASA’s approach is the importance it places on working with stakeholders. The new Earth Science to Action strategy stresses the value of strategic partnerships in delivering tangible societal benefits. Thus, collaborations with international partners, academia, nonprofits, and other agencies will remain pivotal in the effort to meet the need for Earth observations that are accessible, actionable, and beneficial in helping humanity confront urgent challenges.
References
Besso, H., D. Shean, and J. D. Lundquist (2024), Mountain snow depth retrievals from customized processing of ICESat-2 satellite laser altimetry, Remote Sens. Environ., 300, 113843, https://doi.org/10.1016/j.rse.2023.113843.
Bisson, K. M., et al. (2023), Software to enable ocean discoveries: A case study with ICESat-2 and Argo, ESS Open Archive, https://doi.org/10.22541/au.170258908.81399744/v1.
Brown, M. E., et al. (2022), Scientist-stakeholder relationships drive carbon data product transfer effectiveness within NASA program, Environ. Res. Lett., 17(9), 095004, https://doi.org/10.1088/1748-9326/ac87bf.
Campbell, B. A. (2021), ICESat-2 and the Trees Around the GLOBE student research campaign: Looking at Earth’s tree height, one tree at a time, Acta Astronaut., 182, 203–207, https://doi.org/10.1016/j.actaastro.2021.02.002.
Geetha Priya, M., et al. (2022), Estimation of surface melt induced melt pond depths over Amery Ice Shelf, East Antarctica using multispectral and ICESat-2 data, Disaster Adv., 15, 1–8, https://doi.org/10.25303/1508da01008.
Hou, J., et al. (2024), GloLakes: Water storage dynamics for 27 000 lakes globally from 1984 to present derived from satellite altimetry and optical imaging, Earth Syst. Sci. Data, 16, 201–218, https://doi.org/10.5194/essd-16-201-2024.
Lee, C. M., et al. (2022), Systematic integration of applications into the Surface Biology and Geology (SBG) Earth mission architecture study, J. Geophys. Res. Biogeosci., 127(4), e2021JG006720, https://doi.org/10.1029/2021JG006720.
Thompson, D. R., et al. (2022), Ongoing progress toward NASA’s Surface Biology and Geology mission, in IGARSS 2022: 2022 IEEE International Geoscience and Remote Sensing Symposium, pp. 5,007–5,010, Inst. of Electr. and Electron. Eng., Piscataway, N.J., https://doi.org/10.1109/igarss46834.2022.9884123.
Author Information
Molly E. Brown (mbrown52@umd.edu), University of Maryland, College Park; Aimee Neeley, Science Systems and Applications, NASA Goddard Space Flight Center, Greenbelt, Md.; and Thomas Neumann, NASA Goddard Space Flight Center, Greenbelt, Md.
