Coastal Systems

Coastal sciences research supported by the Environmental System Science (ESS) program seeks to address key uncertainties in the fundamental and predictive understanding of integrated coastal environmental systems and to improve their representation in Earth system models. The complexity of coastal sciences provides opportunities for the U.S. Department of Energy (DOE) to bring to bear a broad range of interconnected capabilities and tools to advance models, experiments, and observations across a hierarchy of scales, from local to regional to global dimensions of the Earth system. Additionally, new variable-resolution capabilities in DOE’s Energy Exascale Earth System Model (E3SM) and other advances in process models now enable representation of the critical coastal land-water interface to appropriately capture its highly dynamic processes and drivers. Investigation of coastal systems also addresses all five scientific Grand Challenge areas identified in BER’s Earth and Environmental Systems Sciences Division (EESSD) strategic plan.

Priority Research Objectives

ESS coastal science targets interfaces and transitions between terrestrial and aquatic systems along coastlines and shorelines as areas of great complexity, high uncertainty, and with substantial leverage over local-to-global Earth system processes. Through holistic, hypothesis-driven studies, ESS fundamental research seeks to achieve a systems-level understanding of the processes and drivers of coastal systems and their representation in scale-aware, flexible, and process-rich coastal modeling frameworks. Understanding the physical, biological, and ecological dynamics of complex coastal environments will enable evaluation of their response, feedback, and vulnerability to variable atmospheric, environmental, and human pressures, as well as the implications for intersecting environmental and societal interests. Examples of coastal science questions of interest include:

• Understanding fundamental ecological and hydro-biogeochemical processes at this critical terrestrial interface.
• Appropriately representing multiscale dynamic and transient characteristics of coastal terrestrial-aquatic interfaces.
• Vulnerability, impact, response, and thresholds to chronic and pulse disturbances.
• Bidirectional hydro-biogeochemical feedbacks across the terrestrial-aquatic continuum and with the Earth system.

Additionally, the coastal systems research component of the ESS program develops and uses novel artificial intelligence and machine learning (AI/ML) approaches as well as leveraging of DOE leadership class advanced computing to enable transformational advances in understanding and representing coastal processes in state-of-the-art numerical modeling frameworks. This includes AI/ML-driven coastal system data synthesis and analysis, model uncertainty estimations, and real-time field sensor data assimilation that accelerate scientific workflows.

Why Coastal Sciences Research is Important

Whether at continental margins or the shorelines of large inland waters, coastal zones are highly sensitive and complex environments with dynamic drivers and processes, whose role in both natural and human systems greatly exceeds their geographic extent. Coastal regions are also subject to increasing pressures involving environmental and human-related stresses that may shift or compromise coastal ecosystems, their roles in integrated regional-to-global Earth system processes, and the energy and infrastructure reliant upon them. Examples of coastal science questions of interest include:

• Understanding how to advance scale-aware, multiscale Earth system modeling, recognizing the limited spatial extent and large spatial gradients inherent in coastal zones.
• Understanding how to adequately couple above- and belowground microbial, biogeochemical, and physical processes, noting that coastal environments are exposed to extreme and rapid temporal and spatial change.
• Understanding surface-atmosphere dynamics of coastal systems that are strongly influenced by the change in surface type, temperature, roughness, and other features across sharp coastal boundaries.
• Understanding the dynamics of the coupled human-coastal-environmental system and how the system of components containing cities, energy infrastructure, economies, and the natural environment interact in response to changing conditions and extreme events.

By improving the representation and understanding of critical coastal systems in process-based models and Earth system models, ESS coastal sciences research will empower greater predictive capacity to inform DOE mission and national security needs in coastal regions.

Research Highlights