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Differencing multi-temporal topographic data (radar, lidar, or photogrammetrically derived point clouds or digital elevation models—DEMs) measures landscape change, with broad applications for scientific research, hazard management, industry, and urban planning. The United States Geological Survey’s 3D Elevation Program (3DEP) is an ambitious effort to collect light detection and ranging (lidar) topography over the United States’ lower 48 and Interferometric Synthetic Aperture Radar (IfSAR) in Alaska by 2023. The datasets collected through this program present an important opportunity to characterize topography and topographic change at regional and national scales. We present Indiana statewide topographic differencing results produced from the 2011–2013 and 2016–2020 lidar collections. We discuss the insights, challenges, and lessons learned from conducting large-scale differencing. Challenges include: (1) designing and implementing an automated differencing workflow over 94,000 km2 of high-resolution topography data, (2) ensuring sufficient computing resources, and (3) managing the analysis and visualization of the multiple terabytes of data. We highlight observations including infrastructure development, vegetation growth, and landscape change driven by agricultural practices, fluvial processes, and natural resource extraction. With 3DEP and the U.S. Interagency Elevation Inventory data, at least 37% of the Contiguous 48 U.S. states are already covered by repeat, openly available, high-resolution topography datasets, making topographic differencing possible. 

Abstract Topographic differencing measures landscape change by comparing multitemporal high-resolution topography data sets. Here, we focused on two types of topographic differencing: (1) Vertical differencing is the subtraction of digital elevation models (DEMs) that span an event of interest. (2) Three-dimensional (3-D) differencing measures surface change by registering point clouds with a rigid deformation. We recently released topographic differencing in OpenTopography where users perform on-demand vertical and 3-D differencing via an online interface. OpenTopography is a U.S. National Science Foundation–funded facility that provides access to topographic data and processing tools. While topographic differencing has been applied in numerous research studies, the lack of standardization, particularly of 3-D differencing, requires the customization of processing for individual data sets and hinders the community’s ability to efficiently perform differencing on the growing archive of topography data. Our paper focuses on streamlined techniques with which to efficiently difference data sets with varying spatial resolution and sensor type (i.e., optical vs. light detection and ranging [lidar]) and over variable landscapes. To optimize on-demand differencing, we considered algorithm choice and displacement resolution. The optimal resolution is controlled by point density, landscape characteristics (e.g., leaf-on vs. leaf-off), and data set quality. We provide processing options derived from metadata that allow users to produce optimal high-quality results, while experienced users can fine tune the parameters to suit their needs. We anticipate that the differencing tool will expand access to this state-of-the-art technology, will be a valuable educational tool, and will serve as a template for differencing the growing number of multitemporal topography data sets. 

Data sharing is an integral component of research and academic publications, allowing for independent verification of results. Researchers have the ability to extend and build upon prior research when they are able to efficiently access, validate, and verify the data referenced in publications. Despite the well known benefits of making research data more open, data withholding rates have remained constant. Some disincentives to sharing research data include lack of credit, and fear of misrepresentation of data in the absence of context and provenance. While there are several research data sharing repositories that focus on making research data available, there are no cyberinfrastructure platforms that enable researchers to efficiently validate the authenticity of datasets, track the provenance, view the lineage of the data and verify ownership information. In this paper, we introduce and provide an overview of the NSF funded Open Science Chain, a cyberinfrastructure platform built using blockchain technologies that securely stores metadata and verification information about research data and tracks changes to that data in an auditable manner in order to address issues related to reproducibility and accountability in scientific research. 

Science gateways, also known as advanced web portals, virtual research environments, and more, have changed the face of research and scholarship over the last two decades. Scholars world-wide leverage science gateways for a wide variety of individual research endeavors spanning diverse scientific fields. Evaluating the value of a given gateway to its constituent community is critical in obtaining the financial and human resources to sustain gateway operations. Accordingly, those who run gateways must routinely measure and communicate impact. Just as gateways are varied, their success metrics vary as well. In this survey paper, a variety of different gateways briefly share their approaches. 

Science gateways, also known as advanced web portals, virtual research environments, and more, have changed the face of research and scholarship over the last two decades. Scholars world-wide leverage science gateways for a wide variety of individual research endeavors spanning diverse scientific fields. Evaluating the value of a given gateway to its constituent community is critical in obtaining the financial and human resources to sustain gateway operations. Accordingly, those who run gateways must routinely measure and communicate impact. Just as gateways are varied, their success metrics vary as well. In this survey paper, a variety of different gateways briefly share their approaches. 

Science gateways, also known as advanced web portals, virtual research environments, and more, have changed the face of research and scholarship over the last two decades. Scholars world-wide leverage science gateways for a wide variety of individual research endeavors spanning diverse scientific fields. Evaluating the value of a given gateway to its constituent community is critical in obtaining the financial and human resources to sustain gateway operations. Accordingly, those who run gateways must routinely measure and communicate impact. Just as gateways are varied, their success metrics vary as well. In this survey paper, a variety of different gateways briefly share their approaches. 

Scholars worldwide leverage science gateways/virtual research environments (VREs) for a wide variety of research and education endeavors spanning diverse scientific fields. Evaluating the value of a given science gateway/VRE to its constituent community is critical in obtaining the financial and human resources necessary to sustain operations and increase adoption in the user community. In this article, we feature a variety of exemplar science gateways/VREs and detail how they define impact in terms of, for example, their purpose, operation principles, and size of user base. Further, the exemplars recognize that their science gateways/VREs will continuously evolve with technological advancements and standards in cloud computing platforms, web service architectures, data management tools and cybersecurity. Correspondingly, we present a number of technology advances that could be incorporated in next‐generation science gateways/VREs to enhance their scope and scale of their operations for greater success/impact. The exemplars are selected from owners of science gateways in the Science Gateways Community Institute (SGCI) clientele in the United States, and from the owners of VREs in the International Virtual Research Environment Interest Group (VRE‐IG) of the Research Data Alliance. Thus, community‐driven best practices and technology advances are compiled from diverse expert groups with an international perspective to envisage futuristic science gateway/VRE innovations.