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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2020. A Vision for NSF Earth Sciences 2020-2030: Earth in Time. Washington, DC: The National Academies Press. doi: 10.17226/25761.
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2020. A Vision for NSF Earth Sciences 2020-2030: Earth in Time. Washington, DC: The National Academies Press. doi: 10.17226/25761.
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2020. A Vision for NSF Earth Sciences 2020-2030: Earth in Time. Washington, DC: The National Academies Press. doi: 10.17226/25761.
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2020. A Vision for NSF Earth Sciences 2020-2030: Earth in Time. Washington, DC: The National Academies Press. doi: 10.17226/25761.
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2020. A Vision for NSF Earth Sciences 2020-2030: Earth in Time. Washington, DC: The National Academies Press. doi: 10.17226/25761.
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2020. A Vision for NSF Earth Sciences 2020-2030: Earth in Time. Washington, DC: The National Academies Press. doi: 10.17226/25761.
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2020. A Vision for NSF Earth Sciences 2020-2030: Earth in Time. Washington, DC: The National Academies Press. doi: 10.17226/25761.
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2020. A Vision for NSF Earth Sciences 2020-2030: Earth in Time. Washington, DC: The National Academies Press. doi: 10.17226/25761.
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2020. A Vision for NSF Earth Sciences 2020-2030: Earth in Time. Washington, DC: The National Academies Press. doi: 10.17226/25761.
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Suggested Citation:"Summary." National Academies of Sciences, Engineering, and Medicine. 2020. A Vision for NSF Earth Sciences 2020-2030: Earth in Time. Washington, DC: The National Academies Press. doi: 10.17226/25761.
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Summary The Earth system interacts and connects in unexpected ways—from the interactions of bacteria and rocks to the convective and tectonic processes that build mountains, from the core to the atmosphere, and from the time of Earth’s formation to the present day. While understanding Earth’s interconnected processes is intrinsically interesting and of inherent scientific value, these efforts are made urgent by the need to understand how the Earth can continue to sustain civilization and the planet’s biodiversity. During the past decade, Earth scientists have made conceptual, technological, computational, and observational advances in the study of the Earth as an integrated system. This rapid pace of discovery is likely to accelerate in the future. The Division of Earth Sciences (EAR) at the National Science Foundation (NSF) is the primary federal research agency funding Earth science research, a foundation for fundamental scientific advances and for better understanding of the value and relevance of Earth science to society. The EAR research portfolio is diverse, including investigator-based research projects, multi-investigator programs, investments in facilities, and initiatives within NSF’s Directorate for Geosciences (GEO; which encompasses EAR, the Division of Ocean Sciences, the Division of Atmospheric and Geospace Sciences, and the Office of Polar Programs). EAR also collaborates with other NSF divisions and directorates in cross-cutting programs, as well as with other federal agencies and international entities to provide essential research and infrastructure capabilities to Earth scientists. In 2018, EAR asked the National Academies of Sciences, Engineering, and Medicine’s Board on Earth Sciences and Resources to undertake a decadal survey that provides guidance on future Earth science research priorities, infrastructure and facilities, and partnerships (see Box 1-1 for the full Statement of Task). This report responds to these tasks, presenting a compelling and vibrant vision of the future of Earth science research. PRIORITY SCIENCE QUESTIONS The first task of the committee was to develop priority science questions to guide future EAR research. An important consideration was to develop questions that represent the broad and varied interests of the EAR research community. The committee looked to the community for its visions of the research, infrastructure, partnerships, and training that are needed to sustain and grow vibrant Earth science research. The committee received this input from an online community questionnaire, expert discussions at committee meetings, discussions with colleagues in the EAR research community, listening sessions at scientific conferences, and a comprehensive literature review of community-generated reports, scientific articles, and other sources of information. Guided by this input, the committee identified 12 compelling, high-priority research questions that reflect the importance of geological time, connections Prepublication Version—Subject to further editorial revision. 1

2 A Vision for NSF Earth Sciences 2020-2030: Earth in Time between Earth’s surface and interior, the co-evolution of geology and life, the effects of human activities, and societal relevance. These questions are presented below in spatial order from Earth’s core to the clouds: 1. How is Earth’s internal magnetic field generated? Understanding what has powered the geodynamo through time and what controls its rate of change is crucial for understanding interactions from Earth’s interior to the atmosphere, as well as the human activities that are impacted by the geomagnetic field. 2. When, why, and how did plate tectonics start? Plate tectonics produce and modify the continents, oceans, and atmosphere, but there remains a lack of fundamental understanding of when plate tectonics developed on the Earth, why on the Earth and not on other planetary bodies, and how plate tectonics developed through time. 3. How are critical elements distributed and cycled in the Earth? The cycling of critical elements essential for geologic processes creates suitable conditions for life and provides the ingredients for materials necessary for modern civilization, yet fundamental questions remain about how elements are transported within the Earth, across a range of spatial and temporal scales. 4. What is an earthquake? Earthquake rupture is complex, and the deformation of the Earth occurs over a spectrum of rates and in a variety of styles, leading Earth scientists to reconsider the very nature of earthquakes and the dynamics that drive them. 5. What drives volcanism? Volcanic eruptions have major effects on people, the atmosphere, the hydrosphere, and the Earth itself, creating an urgent need for fundamental research on how magma forms, rises, and erupts in different settings around the world and how these systems have operated throughout geologic time. 6. What are the causes and consequences of topographic change? New technology for measuring topography over geologic to human timescales now makes it possible to address scientific questions linking the deep and surface Earth and urgent societal challenges related to geologic hazards, resources, and climate change. 7. How does the critical zone influence climate? The reactive skin of the terrestrial Earth influences moisture, groundwater, energy, and gas exchanges between the land and atmosphere, and its influence on climate is therefore a vital component of understanding the Earth system and how it has responded and will respond to global change. 8. What does Earth’s past reveal about the dynamics of the climate system? Evidence of both long-term and rapid environmental change in Earth’s history provides key baselines for comparison to modern change, helps to elucidate Earth system dynamics, provides magnitudes and rates of change, and plays a critical role in predicting future change. Prepublication Version—Subject to further editorial revision.

Summary 3 9. How is Earth’s water cycle changing? Understanding current and future changes to the water cycle requires fundamental knowledge of the hydro-terrestrial system and how the water cycle interacts with other physical, biological, and chemical processes. 10. How do biogeochemical cycles evolve? To quantify the role of biology through time in the formation and weathering of rocks and minerals, the cycling of carbon, and the composition of the very air we breathe requires a deeper understanding of biogeochemical cycles. 11. How do geological processes influence biodiversity? The diversity of life on the Earth is a major characteristic of the planet and yet we do not fully know how it came to be. We need to understand how and why diversity has varied over time, environment, and geography, including major events like extinctions. 12. How can Earth science research reduce the risk and toll of geohazards? A predictive and quantitative understanding of geohazards is essential to reduce risk and impacts and to save lives and infrastructure. These questions underscore the fundamentally intertwined nature of the Earth processes. Several overarching themes integrate the individual research questions. First, the Earth is an active, dynamic, open system in which all components interact to shape the state of the planet. Second, the complex geological, geochemical, geophysical, and biological processes that govern Earth-system interactions operate on wide temporal and spatial scales. Finally, a clear understanding of how the Earth currently works as an integrated system (including people as geological agents) and how it has worked in the past is central to predicting how present-day changes, both natural and anthropogenic, are likely to influence human society. For EAR to respond to these priorities requires maintenance of the core disciplinary program strength, with a balance between both individual investigator-driven research and larger programs. INFRASTRUCTURE AND FACILITIES Future observations of the Earth and its constituent materials will rely more than ever on integrating emerging technology, data analysis, and human infrastructure. Infrastructure required to support EAR- funded research consists of the instruments used to make observations and take measurements; the software to gather, analyze, and archive acquired information; the cyberinfrastructure required to model Earth system processes; and the expertise needed to develop, maintain, and operate the instruments and software tools. This report describes the existing infrastructure used by EAR-supported researchers, as well as the future infrastructure needed to accomplish the science priorities described above. EAR supports 30 multi-user facilities that provide infrastructure and expertise for the Earth science research community. The larger facilities support researchers through a combination of instrumentation, cyberinfrastructure, and training, whereas most of the smaller facilities emphasize either instrument-based infrastructure or cyberinfrastructure. The committee found many connections among the existing EAR- supported infrastructure and facilities and the infrastructure needs envisioned for the science priority questions (see Table S-1). In addition, a suite of facilities used by EAR researchers is supported by other divisions within GEO, other parts of NSF, and other federal agencies. A range of instruments, facilities, and capabilities will be needed to fully address the science priority questions over the next decade. Studies of the core and the magnetic field, plate tectonics, critical Prepublication Version—Subject to further editorial revision.

4 A Vision for NSF Earth Sciences 2020-2030: Earth in Time elements, earthquakes, and volcanoes would benefit from enhanced instrumentation to observe and monitor current geologic processes, especially at finer spatial and temporal resolution. This includes seismic and geodetic facilities, rapidly deployable instruments for quick response, laboratory facilities to carry out experiments under a range of environmental conditions, and analytical instrumentation (e.g., high-precision geochronology) to obtain improved records of igneous/metamorphic/tectonic processes operating through Earth’s history. The topography, critical zone, climate, water cycle, and geohazards questions need high-resolution and repeat survey data for change detection; subsurface characterization of material properties; long-term observatories and experimental watersheds to investigate processes; precipitation and runoff monitoring stations; field instrumentation to document water and solid fluxes and their drivers, and moisture, gas, and solute content; satellite-based monitoring data; the ability to quantify chronologies and rates over geologic timescales; and proxy measurements of past environmental conditions. For questions concerning biodiversity and biogeochemical cycles, progress depends on spatio- temporally-constrained paleontological, geochemical, genomic, stratigraphic, and sedimentological records; precise geochronology; and a process-oriented understanding of environmental proxies. All of the questions will require advancements in high-performance computing, improved modeling capabilities, enhanced data curation and standardization, and robust cyberinfrastructure that link together observations across many types of records. To facilitate more transparent evaluation of EAR-supported infrastructure, from individual facilities to the entire EAR infrastructure portfolio, the committee encourages EAR to consider establishing a metrics-based system that can assess the effectiveness and impact of existing facilities. Recommendation: EAR-supported facilities and the entire portfolio of EAR-supported infrastructure should be regularly evaluated using stated criteria in order to prioritize future infrastructure investments, sunset facilities as needed, and adapt to changing science priorities. Possible New Initiatives The committee offers suggestions of possible new initiatives that EAR and the Earth sciences community may wish to consider. These initiatives were chosen because they provide potentially transformative capabilities to support the science priorities, while addressing some of the gaps between existing and needed infrastructure. All of these initiatives originate from EAR research communities, and are based on either community input responses, community white papers or reports, and/or presentations in public sessions. Prepublication Version—Subject to further editorial revision.

Summary 5 TABLE S-1 Connections Between the Science Priorities and Existing Infrastructure and Facilities Abbreviations in first column: SAGE: Seismological Facilities for the Advancement of Geoscience; GAGE: Geodetic Facility for the Advancement of Geoscience; GSECARS: GeoSoilEnviroCARS Synchrotron Radiation Beamlines at the Advanced Photon Source; COMPRES: Consortium for Materials Properties Research in Earth Sciences; PRIME: Purdue Rare Isotope Measurement Laboratory; Wisc SIMS: University of Wisconsin SIMS Lab; UCLA SIMS: University of California, Los Angeles, Ion Probe Lab; ASU SIMS: Arizona State University Ion Probe Lab; NENIMF: Northeast National Ion Microprobe Facility; ALC: Arizona LaserChron Center; CSDCO: Continental Scientific Drilling Coordination Office; LacCore: National Lacustrine Core Facility; ICDP: International Continental Scientific Drilling Program; NCALM: National Center for Airborne Laser Mapping; CTEMPS: Center for Transformative Environmental Monitoring Programs; UTCT: University of Texas High-Resolution Computed X-Ray Tomography Facility; NanoEarth: Virginia Tech National Center for Earth and Environmental Nanotechnology Infrastructure; IRM: Institute for Rock Magnetism; ISC: International Seismological Center; CMT: Global Centroid-Moment-Tensor Project; IEDA: Interdisciplinary Earth Data Alliance; CSDMS: Community Surface Dynamics Modeling System; CUAHSI: Consortium of Universities for the Advancement of Hydrological Science, Inc.; CIG: Computational Infrastructure for Geodynamics; MagIC: Geo-Visualization and Data Analysis using the Magnetics Information Consortium; Neotoma: Neotoma Paleoecology Database and Community; GMT: Generic Mapping Tools. NOTES: Science priorities identified in the report are across the top and existing infrastructure and facilities are down the side. A fully colored box denotes a facility that provides essential capabilities needed to address a priority science question, while a colored circle denotes a facility that is relevant for a question. Determinations were made based on descriptions provided by the facilities, NSF award abstracts, and information taken from the community input questionnaire. Prepublication Version—Subject to further editorial revision.

6 A Vision for NSF Earth Sciences 2020-2030: Earth in Time Several of these initiatives—creating a national consortium for geochronology, establishing a near- surface geophysics center, and funding a U.S.-based very large multi-anvil press user facility—are well developed, with years of community involvement and support, including white papers, endorsement in previous community reports, and/or proposals to NSF. The SZ4D initiative has developed strong community support in recent years, including a well-attended NSF-sponsored workshop and three funded research coordination networks (RCNs), but is still developing its program plan. Other possible initiatives discussed, such as those involving continental drilling, establishing an archive of Earth materials and associated data, and study of the continental critical zone, have various levels of community engagement and program development. Further exploration of these initiatives would need broad involvement of the Earth science community via workshops, white papers, and coordinating mechanisms such as RCNs. In all cases, the committee strongly believes that these initiatives cannot be developed at the expense of EAR’s core disciplinary research programs. EAR’s annual budget has been roughly constant since FY2010 and therefore, because of inflation, has declined in real terms. The initiatives highlighted in this report will be extremely challenging to pursue if the decline in EAR’s budget continues. Recommendation: EAR should fund a National Consortium for Geochronology. Improved constraints on the ages and rates of geologic processes are essential for current and future research in Earth science. A consortium for geochronology will better support EAR-funded researchers while enabling discovery through the development of innovative new instruments, techniques, and applications. Recommendation: EAR should fund a Very Large Multi-Anvil Press Facility. Quantifying the physical and mechanical properties of rocks, minerals, and melts is a cornerstone of EAR research, yet the United States still lacks certain technological capabilities needed to synthesize novel samples and to conduct key physical properties and deformation experiments. Modest investment would enable advances in experimental rock and mineral physics and drive current and future EAR research. Recommendation: EAR should fund a Near-Surface Geophysics Center. Geophysical surveys of the near-surface region (from the ground surface to depths of tens to hundreds of meters) of the Earth have become an essential tool in many Earth science fields. A center would provide access to instrumentation, technical support, and training required to address several of the science priority questions and enable novel observations that lead to new questions and insights. Recommendation: EAR should support continued community development of the SZ4D initiative, including the Community Network for Volcanic Eruption Response. This community-led initiative seeks a deeper understanding of subduction processes that drive the evolution of Earth’s interior and that create devastating geohazards such as earthquakes, tsunamis, and volcanic eruptions. Prepublication Version—Subject to further editorial revision.

Summary 7 Recommendation: EAR should encourage the community to explore a Continental Critical Zone initiative. Characterizing the subsurface critical zone to its full depth at the continental scale is needed to advance understanding of water, carbon, and nutrient cycles; landscape evolution and hazards prediction; and land-climate interactions. Recommendation: EAR should encourage the community to explore a Continental Scientific Drilling initiative. Improved mechanisms to support U.S. researchers’ involvement in continental drilling would enhance access to continuous geologic records needed to address many of the priority questions. Recommendation: EAR should facilitate a community working group to develop mechanisms for archiving and curating currently existing and future physical samples and for funding such efforts. New questions and analytical methods are continually introduced, making physical archives and associated metadata invaluable to scientists many years after the relevant materials were collected. Even if time and funding were available, it would not always be possible to replicate a physical collection as some materials are unique or ephemeral or were found only at localities that are no longer accessible. Recommendations for Cyberinfrastructure The committee also presents a series of recommendations that aim to advance EAR research through improvements to cyberinfrastructure that support computing and modeling capabilities, as well as data integration, synthesis, and curation. Earth science is experiencing an explosion of data acquisition capability and rapidly increasing computational demands, as models advance to exploit these data and ever-increasing hardware capabilities. Addressing the science priority questions will require advanced computational capabilities and new methods of data integration to enable high-resolution imaging of Earth structure and of Earth materials; innovative modeling of physical, chemical, and biological processes; and better constraints on Earth’s dynamical evolution. Recommendation: EAR should initiate a community-based standing committee to advise EAR regarding cyberinfrastructure needs and advances. In order to make optimal investments of resources in the coming decade, EAR needs regular guidance about the needs of its researchers, opportunities in cyberinfrastructure, and the rapidly evolving computational landscape. Prepublication Version—Subject to further editorial revision.

8 A Vision for NSF Earth Sciences 2020-2030: Earth in Time Recommendation: EAR should develop and implement a strategy to provide support for FAIR practices within community-based data efforts. FAIR 1 data standards will improve the longevity, utility, and impact of EAR-funded data. Although NSF promotes FAIR data practices in spirit, the financial cost makes EAR support for long-term, compliant data storage difficult in times of level budgets. Recommendations for Human Infrastructure Finally, the committee emphasizes the need for human infrastructure. Highly trained individuals in science, technology, engineering, and mathematics (STEM) fields are an essential part of Earth science infrastructure and are central to future breakthroughs and the continued relevance of geoscience to societal issues, yet there are challenges to recruit and retain a highly competent and inclusive STEM workforce with expertise in both Earth and data sciences. Recommendation: EAR should enhance its existing efforts to provide leadership, investment, and centralized guidance to improve diversity, equity, and inclusion within the Earth science community. Improved inclusion of diverse perspectives in all aspects of research and collaboration benefits team innovation, problem solving, and effectiveness, and can enhance the relevance of science to currently underrepresented communities. Recommendation: EAR should commit to long-term funding that develops and sustains technical staff capacity, stability, and competitiveness. Highly skilled staff are needed to help tackle the questions about the complex Earth system at analytical, computational, and instrumentation development facilities. Preparing the next generation of Earth scientists for an increasingly technological field requires strengthening financial support for technical staff. Implementing the recommendations for cyberinfrastructure and human infrastructure will require not just a commitment of funding, but significant changes for the Earth science community in terms of policies and practices. PARTNERSHIPS EAR has established strong relationships across the GEO Directorate in order to meet the needs of advancing research across the Earth system, not just within Earth sciences. Components of the Earth system do not adhere to the administrative boundaries of GEO. To meet the continued and growing need to work across disciplines, EAR plays an active role in ongoing and new NSF cross-division and cross-directorate activities (e.g., Coastlines and People; Innovations at the Nexus of Food, Energy, and Water Systems). 1 Findable, Accessible, Interoperable, Reusable. See Wilkinson, M. D., M. Dumontier, I. J. Aalbersberg, G. Appleton, M. Axton, A. Baak, N. Blomberg, J.-W. Boiten, L. B. da Silva Santos, P. E. Bourne, J. Bouwman, A. J. Brookes, T. Clark, M. Crosas, I. Dillo, O. Dumon, S. Edmunds, C. T. Evelo, R. Finkers, A. Gonzalez-Beltran, A. J. G. Gray, P. Groth, C. Goble, J. S. Grethe, J. Heringa, P. A. C. ’t Hoen, R. Hooft, T. Kuhn, R. Kok, J. Kok, S. J. Lusher, M. E. Martone, A. Mons, A. L. Packer, B. Persson, P. Rocca-Serra, M. Roos, R. van Schaik, S.-A. Sansone, E. Schultes, T. Sengstag, T. Slater, G. Strawn, M. A. Swertz, M. Thompson, J. van der Lei, E. van Mulligen, J. Velterop, A. Waagmeester, P. Wittenburg, K. Wolstencroft, J. Zhao, and B. Mons. 2016. The FAIR guiding principles for scientific data management and stewardship. Scientific Data 3(1):160018. DOI: 10.1038/sdata.2016.18. Prepublication Version—Subject to further editorial revision.

Summary 9 Recommendation: EAR should collaborate with other GEO divisions and other agencies to fund geoscience research that crosses boundaries, such as shorelines, high latitudes, and the atmosphere– land interface. The points of intersection for basic and applied research among multiple NSF divisions and directorates, federal agencies, and international partners present many opportunities for partnership and collaboration. Seizing these opportunities not only advances research objectives, but also allows for more efficient leveraging of relevant facilities and infrastructure. As research becomes more inter- and transdisciplinary, there will be continued opportunities to strengthen and expand both formal and informal collaborations. A nimble EAR can quickly take advantage of the shifting frontiers in basic science and interdisciplinary research. There is a continued need to better articulate and publicize the important benefits of EAR research to policy makers and the public. In discussions with other NSF units and federal agencies, two repeated themes were the successful relationships that EAR has built with other directorates and EAR’s involvement in productive cross-directorate, cross-agency, and international partnerships. The National Aeronautics and Space Administration (NASA), the U.S. Department of Energy (DOE), and the U.S. Geological Survey (USGS) provide important capabilities supporting EAR research. Multiple opportunities exist to continue and expand partnerships with other federal agencies. Partnerships with NASA and USGS could include quantifying water storage in aquifers and reservoirs; understanding processes affecting sea level rise; exploring fundamental research related to volcanoes, earthquakes, and landslides (and implications for risks to people and places); and investigating effects of biogeochemical processes. All of these are relevant to EAR research and suggest possibilities for partnerships that combine satellite and aircraft remote sensing with detailed process studies and ground- based observations. Additionally, DOE invests significantly in infrastructure that supports Earth science research at synchrotron radiation facilities. Recommendation: EAR should proactively partner with other NSF divisions and other federal agencies to advance novel societally relevant research. Cross-division collaboration and cross-agency partnerships work best when a strong common interest and robust community input and involvement exist. Determining which areas of research might be valuable for collaboration between NSF and other agencies can be challenging, because mission agencies generally have less flexibility in funding research topics than does NSF. However, there are important advantages when it is possible to converge on a research partnership. Developing and sustaining partnerships do require time and effort of program officers, and the extra administrative workload is a potential obstacle to partnering. A DECADAL VISION FOR EARTH SCIENCES EAR’s mission is more important and urgent than ever before, with profound opportunities for discovery and potential for immense societal consequences. Today’s Earth science landscape is vastly different from what it was only a decade ago. Continued progress in understanding will make society better prepared to meet the challenges of a changing Earth, especially if scientific advances can be effectively communicated to the public. In this “all hands on deck” moment a demographically and scientifically diverse group of Earth scientists is needed, working both individually and in collaborative networks, to create and deploy cutting-edge analytical, computational, and field-based research methods, in an open environment where success builds expeditiously on success. Prepublication Version—Subject to further editorial revision.

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The Earth system functions and connects in unexpected ways - from the microscopic interactions of bacteria and rocks to the macro-scale processes that build and erode mountains and regulate Earth’s climate. Efforts to study Earth's intertwined processes are made even more pertinent and urgent by the need to understand how the Earth can continue to sustain both civilization and the planet's biodiversity.

A Vision for NSF Earth Sciences 2020-2030: Earth in Time provides recommendations to help the National Science Foundation plan and support the next decade of Earth science research, focusing on research priorities, infrastructure and facilities, and partnerships. This report presents a compelling and vibrant vision of the future of Earth science research.

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