Earth has a suite of complex, dynamic geosystems governing the past evolution, current state, and future conditions that the planet and all humans experience. As the Earth sciences have matured over the past two centuries, developing subdisciplinary specialties that can address specific aspects of Earth’s structure, processes, and history with steadily improving resolution, the interdisciplinary nature of the various dynamic geosystems has come into increasing focus. Continuing theoretical and technical improvements are advancing the capabilities of all subdisciplines of the Earth sciences to document the geological record of terrestrial change, to observe active processes in the present-day Earth from surface to inner core, and to make more realistic simulations of complex dynamic processes, and these efforts need to be sustained. However, the areas of greatest near-term research opportunity that are highlighted in this report all involve integrative interdisciplinary efforts focused on specific dynamic geosystems of the past and present.
The 2001 National Research Council (NRC) report Basic Research Opportunities in Earth Science (BROES) described how basic research in the Earth sciences serves five national imperatives: (1) discovery, use, and conservation of natural resources; (2) characterization and mitigation of natural hazards; (3) geotechnical support of commercial and infrastructure development; (4) stewardship of the environment; and (5) terrestrial surveillance for global security and national defense. This perspective is even more pressing today, and will persist into the future, with ever-growing emphasis. Today’s world—with headlines dominated by issues involving fossil fuel and water resources, earthquake and tsunami disasters claiming hundreds of thousands of lives and causing hundreds of billions of dollars in damages, profound environmental changes associated with the evolving climate system, and nuclear weapons proliferation and testing—has many urgent societal issues that need to be informed by sound understanding of the Earth sciences.
A national strategy to sustain basic research and training of expertise across the full spectrum of the Earth sciences is motivated by these national imperatives. This assessment of research opportunities for the next decade identifies many of the ways that the Earth sciences can sustain and enhance contributions to society. The National Science Foundation (NSF), through its Division of Earth Sciences (EAR), is the only federal agency that maintains significant funding of both curiosity-driven and strategic research in all core subdisciplines of the Earth sciences. The health and effectiveness of the EAR program are therefore central to a strong national effort in the Earth sciences, and increased investment in this arena is needed to fully capitalize on the potential contributions that the Earth sciences can make. A decade after the BROES report, NSF again requested that the NRC form an ad hoc committee to identify new research opportunities in the Earth sciences as they relate to the responsibilities of EAR. In particular, the committee was asked to undertake four tasks:
1. Identify high-priority new and emerging research opportunities in the Earth sciences
over the next decade, including surface and deep Earth processes and interdisciplinary research with fields such as ocean and atmospheric sciences, biology, engineering, computer science, and social and behavioral sciences.
2. Identify key instrumentation and facilities needed to support these new and emerging research opportunities.
3. Describe opportunities for increased cooperation in these new and emerging areas between EAR and other government agency programs, industry, and international programs.
4. Suggest new ways that EAR can help train the next generation of Earth scientists, support young investigators, and increase the participation of underrepresented groups in the field.
The committee was not asked to evaluate existing EAR programs or make budgetary recommendations.
NEW RESEARCH OPPORTUNITIES IN THE EARTH SCIENCES
Basic research in the Earth sciences encompasses a wide range of physical, chemical, and biological processes that interact and combine in complex ways to produce a spectrum of terrestrial systems. EAR is currently sponsoring investigations on geosystems that range in geographic scale from global—climate, plate tectonics, and Earth’s core dynamo—to regional and local—mountain belts and sedimentary basins, active fault networks, volcanoes, groundwater reservoirs, watersheds, and soil systems—to micro-mineral interactions, microbiology, and pore fluid interactions. Research at all of these scales has been accelerated by a combination of conceptual advances and across-the-board improvements in observational capabilities and information technologies. The committee has identified seven topics involving major dynamic geosystems that can only be fully quantified by interdisciplinary approaches, organized by scale and disciplinary participation related to the EAR Deep Earth Processes and Surface Earth Processes sections: (1) the early Earth; (2) thermo-chemical internal dynamics and volatile distribution; (3) faulting and deformation processes; (4) interactions among climate, surface processes, tectonics, and deeper Earth processes; (5) co-evolution of life, environment, and climate; (6) coupled hydrogeomorphic-ecosystem responses to natural and anthropogenic change; and (7) biogeochemical and water cycles in terrestrial environments and impacts of global change. These research areas span a range of fundamental grand challenge questions from how the planet’s interior works to the evolution of the surface environment. In addition, the expanding demand for accurate geological dates to support many of the research opportunities motivates consideration of restructuring how EAR supports the geochronology facilities that must innovate methodologies, train next-generation geochemists, and service burgeoning demands for what is seldom routine dating of samples.
PRINCIPAL FINDINGS AND RECOMMENDATIONS
EAR has generally done an excellent job overall in developing and maintaining a balance among programs that support investigator-driven disciplinary research, problem-focused programs involving multidisciplinary research, and equipment-oriented programs for new instrumentation and facilities. The committee offers recommendations that address the evolving science requirements in all three of these programmatic areas. These recommendations pertain primarily to new mechanisms that will allow EAR to foster new research opportunities identified in this report.
Long-Term Investigator-Driven Science
In the next decade, and likely throughout the entire century to come, the quest to quantify Earth’s dynamic geosystems by establishing their history, current behavior, and future evolution will involve integrative interdisciplinary approaches that build on basic research advances in subdisciplinary capabilities. The primary recommendations in this report highlight opportunities to pursue integrative activities with high potential impact. However, as in many previous NRC reports on scientific research opportunities, this report again emphasizes the importance of sustaining subdisciplinary-based core Earth science research and facilities. Individual investigator-driven science remains the most creative and effective way to enhance the knowledge base upon which integrative efforts can
build. This report gives numerous findings that reaffirm this essential need to sustain the basic Earth sciences by individual investigators, because this is the single most important mechanism for maintaining and enhancing disciplinary strength in the field. EAR is now the almost exclusive basis for supporting the full spectrum of basic Earth science research.
New Research Opportunities
The Early Earth
Many uniquely critical events occurred early in Earth’s history: delivery of the material that built Earth; formation of the Moon; and the differentiation events that formed the core and earliest crust, the oceans, and the atmosphere. Earth’s early history set the stage for its subsequent dynamic and geochemical evolution, from an environment dominated by impacts and magma oceans to the habitable environment dominated by the plate tectonics of today. There are multiple avenues for enhancing our understanding of this formative stage in our planet’s history, including expanding the inventory of early Earth samples, fostering new technologies for analysis of ancient materials, quantification of early chronology using novel isotope systems, and developing models that simulate the highly energetic conditions of the early Earth.
Recommendation: EAR should take appropriate steps to encourage work on the history and fundamental physical and chemical processes that governed the evolution of Earth from the time of its accretion through the end of late heavy bombardment and into the early Archaen, perhaps by establishing a specific initiative on early Earth. Specific program objectives and scope may be developed through community workshops that prepare a science plan preceding a separate call for proposals.
Thermo-Chemical Internal Dynamics and Volatile Distribution
The huge dynamic circulation systems in Earth’s mantle and core circulate heat and materials, drive the long-term evolution of continents, generate the magnetic field, and cycle volatiles into and out of the interior, maintaining bulk chemistry of the oceans and atmosphere. Resolving the present-day configuration and processes of the mantle and core convective systems with high resolution is a key undertaking for developing models of the past and future evolution of the system, the thermal evolution of Earth, and the volatile flux in Earth. Collective advances in imaging capabilities, experimental and theoretical determinations of material properties under extreme pressures and temperatures, geochemistry, and increasingly realistic representations of the dynamic circulation in the mantle and core have placed the discipline on the threshold of breakthroughs in understanding the thermo-chemical dynamics and the distribution and cycling of volatiles. Enhancing resolution of the various approaches is essential to resolving the outstanding questions about how Earth’s interior works.
Recommendation: EAR should pursue the development of facilities and capabilities that will improve spatial resolution of deep structures in the mantle and core, such as dense seismic arrays that can be deployed in various favorable locations around Earth, enhanced computational software and hardware to enable increased resolution of three-dimensional geodynamical models, and improved high-resolution experimental and theoretical mineral physics investigations. This will provide definitive tests of many hypotheses for deep Earth structure and evolution advanced over the past decade. The large scope of such facilities will require a lengthy development and review process, and building the framework for such an initiative needs to commence soon.
Faulting and Deformation Processes
Exciting discoveries, driven by increased instrumentation around fault zones, have been made regarding the spectrum of faulting processes and mechanisms. These present an opportunity to make significant progress on understanding faulting, related deformation processes, and resulting earthquake hazards. Earthquake science involves a complex geosystem with multiscale processes from the microscale, such as the controls on surface friction, up to the regional-scale processes of sedimentary basin reverberation and excitation of tsunamis by ocean water displacements. There have been significant advances in this geosystem perspective, with interactions between researchers with expertise
spanning laboratory friction experiments, observational and theoretical seismology, geodesy, structural geology, earthquake engineering, field geology, volcanology, magnetotellurics, and deep drilling. In the next decade integrative efforts built around active fault zone and subduction zone laboratories hold promise of greatly advancing our understanding of faulting and deformation processes and associated roles of fluid, volatile, and material fluxes.
Recommendation: EAR should pursue integrated interdisciplinary quantification of the spectrum of fault slip behavior and its relation to fluxes of sediments, fluids, and volatiles in the fault zone. The successful approach of fault zone and subduction zone observatories should be sustained, because these provide an integrative geosystems framework for understanding faulting and associated deformation processes. The related EarthScope project is exploring the structure and evolution of the North American continent using thousands of coordinated geophysical instruments. There is great scientific value to be gained in completing this project, as envisioned, through 2018.
Interactions Among Climate, Surface Processes, Tectonics, and Deeper Earth Processes
The broad interactions among climate, Earth surface processes, and tectonics are areas of compelling research opportunities that center on interactions among topography, hydrology and hydrogeology, physical and chemical denudation, sedimentary deposition, and deformation in tectonically active mountain belts. There is a strong need for geomorphic transport laws that account for climate and the role of biota to describe and quantify river and glacial incision, landslides, and the production, transport, and deposition of sediment. These transport laws will allow us to integrate the effects of event-based processes into long-term system behavior. New understanding of the dynamic interactions among climate, Earth’s surface, and tectonics over geomorphic to geological timescales will require increased access to, and new developments in, thermochronometry, methods for dating geomorphological surfaces, Light Detection And Ranging (LiDAR), satellite imagery, modeling capabilities, experimental methods, and field instrumentation and studies. The existing EAR Continental Dynamics program1 covers many of these themes, but a stronger link to climate and surface processes has the potential for significant advances.
Recommendation: EAR should take appropriate steps to encourage work on interactions among climate, surface processes, tectonics, and deeper Earth processes either through a new interdisciplinary program or perhaps by expanding the focus of the EAR Continental Dynamics program to accommodate the broader research agenda of these interdisciplinary subthemes.
Co-evolution of Life, Environment, and Climate
The deep-time geological record has provided a compelling narrative of changes in Earth’s climate, environment, and evolving life, many of which provide analogs, insight, and context for understanding human’s place in the Earth system and current anthropogenic change. However, the complexity of this bio-geosystem is only now being fully realized, with new analytic tools from geochemistry, paleontology, and biology enabling unprecedented exploration of the coupled time-evolution of past Earth surface conditions, including temperature, atmospheric chemistry, hydroclimates, the chemical composition of the ocean, and the interrelationship and physiologies of ancient life forms. Concerted application of the interdisciplinary capabilities to the deep-time record will provide breakthrough understanding of this profound and nonlinear bio-geosystem.
Recommendation: EAR should develop a mechanism to enable team-based interdisciplinary science-driven projects involving stratigraphy, sedimentology, paleontology, proxy development, calibration and application studies, geochronology, and climate modeling at appropriately resolved scales of time and space, to understand the major linked events of environmental, climate and biotic change at a mechanistic level. Such projects could be expected to be cross program and cross directorate.
Coupled Hydrogeomorphic-Ecosystem Response to Natural and Anthropogenic Change
Understanding the response of large-scale landscapes and ecosystems to disturbance and climate change requires greater mechanistic understanding of the interactions and feedbacks among hydrological drivers, landscape morphology, and biotic processes. Advancing the science requires better theory, observations, and models relating spatial patterns and temporal variability of landscape drivers (topography, hydrology, geology) to the dynamics of biotic communities, including identification of hydrological and morphological leading indicators of landscape and ecosystem state change. This will require integrated monitoring of landscape processes and development of new instrumentation and data archives to support and test models—work that could take advantage of large-scale restoration efforts and documented historical change as controlled experiments.
Recommendation: EAR should facilitate research on coupled hydrogeomorphic–ecosystem response to climate change and disturbance. In particular, the committee recommends that EAR target interdisciplinary research on coastal environments. This initiative would lay the groundwork for understanding and forecasting the response of coastal landscapes to sea-level rise, climate change, and human and natural disturbance, which will fill an existing gap at NSF and should involve coordination with the Division of Ocean Sciences, U.S. Geological Survey (USGS), and National Oceanic and Atmospheric Administration (NOAA).
Biogeochemical and Water Cycles in Terrestrial Environments and Impacts of Global Change
Humans are altering the physical, chemical, and biological states of and feedbacks among essential components of Earth’s detailed surface system. At the same time, atmospheric temperature and carbon dioxide levels have increased and are impacting carbon storage in the terrestrial environment, the water cycle, and a range of intertwined biogeochemical cycles and atmospheric properties that feed back on climate and ecosystems. Advancing our understanding of integrated soil, water, and biogeochemical dynamics in the fine-scale critical zone requires new theory, coupled systems models, and new data. New advances in our ability to understand and quantitatively simulate carbon, nutrient, water, and rock cycling will depend on new measurement approaches and instrumentation that capture spatial and temporal variability in atmospheric and land use inputs superimposed on complex vegetation patterns and underlying anisotropic subsurface geomedia.
Recommendation: EAR should continue to support programs and initiatives focused on integrated studies of the cycling of water, carbon, nutrients, and geological materials in the terrestrial environment, including mechanisms and reactions of soil formation; hydrological and nutrient cycling; perturbations related to human activities; and more generally the cycling of carbon between surface environments and the atmosphere and its feedbacks with climate, biogeochemical processes, and ecosystems.
Instrumentation and Facilities to Support Research Opportunities
Each research opportunity has specific disciplinary-based data collection, instrumentation, and facilities associated with it, but there are some cross-cutting intersections of needs. The global span of the geosystems involved requires synoptic observations provided by global networks of geophysical, geochemical, petrological, and environmental facilities and data collection efforts. These include long-term observatories such as provided by seismic and geodetic networks currently supported by EAR and other agencies, as well as portable instrument facilities for hydrology, rock and fossil sampling and drilling, seismology, geodesy, and magnetotellurics, with specific findings given in Chapter 3. EAR has achieved a reasonable balance in funding of facilities, core disciplinary research programs, and interdisciplinary initiatives. Maintaining this balance as the budget grows is important; while new interdisciplinary or instrumentation initiatives often provide compelling rationale for budgetary growth, balancing the portfolio of resources (particularly with investment in the core single-investigator programs) over time is very desirable for sustaining the overall health of the effort.
Recommendation: EAR should explore new mechanisms for geochronology laboratories that will service the geochronology requirements of the broad suite of research opportunities while sustaining technical advances in methodologies. The approaches may involve coordination of multiple facilities and investment in service facilities and may differ for distinct geochronology systems.
Partnerships and Coordination
Agency partnerships led by EAR will continue to be essential for attaining many of the research objectives identified in this report. Well-managed partnerships can foster broadly based research communities, leverage limited resources, and promote fruitful synergies. Among the highlighted research opportunities, the Early Earth opportunities overlap with mission objectives of the National Aeronautics and Space Administration (NASA) and research activities supported by the U.S. Department of Energy; the study of Earth tectonics is enabled by measurements from NASA and U.S. Department of Defense–supported satellites, and studies of surficial processes and coastal dynamics address problems that are at the core of the missions of the USGS, NOAA, and U.S. Forest Service. Continued efforts to develop and maintain these partnerships are key to maximizing the impact of EAR funding.
Training the Next Generation and Diversifying the Researcher Community
Capitalizing on the research opportunities set out in this report will require researchers with the skills and knowledge to advance the science, but attracting new students and providing the appropriate training remain major challenges in the United States. Increasing the participation of historically underrepresented groups is an equally important and directly related challenge, and there remains an uneven minority exposure to science and math as well as a significant science knowledge disparity between poor and affluent students. The EAR division is working to enhance diversity, education, and knowledge transfer through several outreach efforts, and these efforts can continue to be enhanced. There are several important ways that EAR might do so, including establishing Advanced Placement Earth science courses in high schools, promoting early awareness of the Earth sciences on college campuses, developing place-based research and education programs that incorporate indigenous landscapes and ways of thinking, and fostering the scientist communicator.