3 research outputs found
The U.S. Arctic Observing Viewer: A Web-Mapping Application for Enhancing Environmental Observation of the Changing Arctic
Although much progress has been made with various Arctic Observing efforts, assessing that progress can be difficult. What data collection efforts are established or underway? Where? By whom? To help meet the strategic needs of programs such as the U.S. Study of Environmental Arctic Change (SEARCH), the Arctic Observing Network (AON), Sustaining Arctic Observing Networks (SAON) and related initiatives, an update has been released for the Arctic Observing Viewer (AOV; http://ArcticObservingViewer.org). This web mapping application and information system has begun to compile the who, what, where, and when for thousands of data collection sites (such as boreholes, ship tracks, buoys, towers, sampling stations, sensor networks, vegetation sites, stream gauges, and observatories) wherever marine, terrestrial, or atmospheric data are collected. Contributing partners for this collaborative resource include the U.S. NSF, ACADIS, ADIwg, AOOS, a2dc, AON, ARMAP, BAID, CAFF, IASOA, INTERACT, and others. While focusing on U.S. activities, the AOV welcomes information exchange with international groups for mutual benefit. Users can visualize, navigate, select, search, draw, print, and more. AOV is founded on principles of interoperability, with open metadata and web service standards, so that agencies and organizations can use AOV tools and services for their own purposes. In this way, AOV will reinforce and complement other distributed yet interoperable cyber-resources and will help science planners, funding agencies, researchers, data specialists, and others to assess status, identify overlap, fill gaps, optimize sampling design, refine network performance, clarify directions, access data, coordinate logistics, collaborate, and more in order to meet Arctic Observing goals.MalgrĂ© les progrĂšs rĂ©alisĂ©s dans le cadre de nombreux efforts dâobservation de lâArctique, les progrĂšs peuvent ĂȘtre difficiles Ă Ă©valuer. Quelles initiatives de collecte de donnĂ©es sont en cours ou sont Ă©tablies? Ă quel endroit? Et qui gĂšre ces initiatives? Pour aider Ă rĂ©pondre aux besoins stratĂ©giques de programmes comme ceux de lâorganisme amĂ©ricain Study of Environmental Arctic Change (SEARCH), du rĂ©seau Arctic Observing Network (AON), des rĂ©seaux Sustaining Arctic Observing Networks (SAON) et dâautres programmes connexes, on a procĂ©dĂ© Ă la mise Ă jour de lâArctic Observing Viewer (AOV; http://ArcticObservingViewer.org). Ce systĂšme dâinformation jumelĂ© Ă une application de mappage sur le Web a amorcĂ© la compilation des coordonnĂ©es et des renseignements se rapportant Ă des milliers de sites de collecte de donnĂ©es (comme les trous de forage, les trajets de navires, les bouĂ©es, les tours, les stations dâĂ©chantillonnage, les rĂ©seaux de capteurs, les sites de vĂ©gĂ©tation, les fluviomĂštres et les observatoires) oĂč des donnĂ©es marines, terrestres ou atmosphĂ©riques sont prĂ©levĂ©es. Parmi les partenaires qui collaborent Ă cette ressource, notons U.S. NSF, ACADIS, ADIwg, AOOS, a2dc, AON, ARMAP, BAID, CAFF, IASOA, INTERACT et dâautres encore. Bien que lâAOV se concentre sur les activitĂ©s amĂ©ricaines, il accepte lâĂ©change dâinformation avec des groupes internationaux lorsquâil existe des avantages mutuels. Les utilisateurs peuvent visualiser les donnĂ©es, naviguer dans le systĂšme, faire des sĂ©lections et des recherches, dessiner, imprimer et ainsi de suite. LâAOV fonctionne moyennant des principes dâinteropĂ©rabilitĂ©, avec des mĂ©tadonnĂ©es ouvertes et des normes de service sur le Web afin que les organismes et les organisations puissent utiliser les outils et les services de lâAOV pour leurs propres fins. De cette façon, lâAOV sera en mesure de consolider et de complĂ©ter dâautres cyberressources Ă la fois rĂ©parties et interopĂ©rables, en plus dâaider les planificateurs de la science, les bailleurs de fonds, les chercheurs, les spĂ©cialistes des donnĂ©es et dâautres encore Ă Ă©valuer les statuts, Ă repĂ©rer les dĂ©doublements, Ă combler les Ă©carts, Ă optimiser les plans dâĂ©chantillonnage, Ă raffiner le rendement des rĂ©seaux, Ă clarifier les consignes, Ă accĂ©der aux donnĂ©es, Ă coordonner la logistique, Ă collaborer et ainsi de suite afin de rĂ©pondre aux objectifs dâobservation de lâArctique
Global application of an unoccupied aerial vehicle photogrammetry protocol for predicting aboveground biomass in nonâforest ecosystems
P. 1-15Non-forest ecosystems, dominated by shrubs, grasses and herbaceous plants, provide ecosystem services including carbon sequestration and forage for grazing, and are highly sensitive to climatic changes. Yet these ecosystems are poorly represented in remotely sensed biomass products and are undersampled by in situ monitoring. Current global change threats emphasize the need for new tools to capture biomass change in non-forest ecosystems at appropriate scales. Here we developed and deployed a new protocol for photogrammetric height using unoccupied aerial vehicle (UAV) images to test its capability for delivering standardized measurements of biomass across a globally distributed field experiment. We assessed whether canopy height inferred from UAV photogrammetry allows the prediction of aboveground biomass (AGB) across low-stature plant species by conducting 38 photogrammetric surveys over 741 harvested plots to sample 50 species. We found mean canopy height was strongly predictive of AGB across species, with a median adjusted R2 of 0.87 (ranging from 0.46 to 0.99) and median prediction error from leave-one-out cross-validation of 3.9%. Biomass per-unit-of-height was similar within but different among, plant functional types. We found that photogrammetric reconstructions of canopy height were sensitive to wind speed but not sun elevation during surveys. We demonstrated that our photogrammetric approach produced generalizable measurements across growth forms and environmental settings and yielded accuracies as good as those obtained from in situ approaches. We demonstrate that using a standardized approach for UAV photogrammetry can deliver accurate AGB estimates across a wide range of dynamic and heterogeneous ecosystems. Many academic and land management institutions have the technical capacity to deploy these approaches over extents of 1â10 haâ1. Photogrammetric approaches could provide much-needed information required to calibrate and validate the vegetation models and satellite-derived biomass products that are essential to understand vulnerable and understudied non-forested ecosystems around the globe.S
Semi-Automated Semantic Segmentation of Arctic Shorelines Using Very High-Resolution Airborne Imagery, Spectral Indices and Weakly Supervised Machine Learning Approaches
Precise coastal shoreline mapping is essential for monitoring changes in erosion rates, surface hydrology, and ecosystem structure and function. Monitoring water bodies in the Arctic National Wildlife Refuge (ANWR) is of high importance, especially considering the potential for oil and natural gas exploration in the region. In this work, we propose a modified variant of the Deep Neural Network based U-Net Architecture for the automated mapping of 4 Band Orthorectified NOAA Airborne Imagery using sparsely labeled training data and compare it to the performance of traditional Machine Learning (ML) based approachesânamely, random forest, xgboostâand spectral water indicesâNormalized Difference Water Index (NDWI), and Normalized Difference Surface Water Index (NDSWI)âto support shoreline mapping of Arctic coastlines. We conclude that it is possible to modify the U-Net model to accept sparse labels as input and the results are comparable to other ML methods (an Intersection-over-Union (IoU) of 94.86% using U-Net vs. an IoU of 95.05% using the best performing method)