Seamless, high-resolution topobathymetric digital elevation models (DEMs) of rivers are important for generating hydrodynamic models, studying water quality and related ecological issues, modeling flood vulnerability, and numerous other applications. However, such DEMs can be difficult to generate, due to a lack of topographic and bathymetric source data. Even where the...
Unmanned aircraft systems (UAS), also known as drones, are an increasingly popular method of collecting surveying and mapping data. Two common drone-based mapping techniques are lidar and structure from motion (SfM) photogrammetry, and a frequently-heard (yet nearly impossible to answer) question is: “which is better?” The most common metric for...
Modern geospatial data are frequently represented in some type of three-dimensional (3D) coordinate system, for example geodetic latitude, longitude, and ellipsoid height (φ, λ, h) derived from Global Navigation Satellite Systems (GNSS). But for engineering and surveying work, φ, λ, h coordinates are usually converted to a topocentric system consisting...
The Experimental Advanced Airborne Research Lidar ‐ B (EAARL‐B), which was built and deployed by the U.S. Geological Survey (USGS) in 2014, is a novel topographic‐bathymetric lidar system. While retaining a number of features that were pioneered in the original National Aeronautics and Space Administration (NASA) EAARL system (e.g., low...
Imagery acquired from unmanned aircraft systems (UAS) and processed with structure from motion (SfM) – multi-view stereo (MVS) algorithms provides transformative new capabilities for surveying and mapping. Together, these new tools are leading to a democratization of airborne surveying and mapping by enabling similar capabilities (including similar or better accuracies,...
Despite numerous techniques for measuring and estimating water depth, bathymetry in the nearshore zone is notoriously difficult to map. Dangerous sea states, noisy environmental conditions, and expensive survey operations, particularly in remote areas, contribute to the difficulties of obtaining data along the coast. Global datasets, derived mainly from satellite altimetry...
Marine debris is a chronic and increasingly pervasive problem for coastal regions around the world. Debris poses environmental risks, threats to wildlife, and degradation of the natural environment. Recent research has shown the advantages of uncrewed aircraft systems (UAS) for detection and recognition of marine debris, including the ability to...
Interest in mapping bathymetry from multispectral satellite imagery has grown steadily since the 1970s. Notwithstanding the significant advancements made during this time, one limitation is that the group of algorithms collectively referred to as Satellite Derived Bathymetry (SDB) generally require “seed depths,” hindering their use for areas lacking reliable reference...
Bathymetry data (measurements of the elevations of submerged surfaces like the seafloor and lake beds) are an important factor in many scientific, economic, and engineering disciplines. Bathymetric surveys are widely used for benthic habitat mapping, flood inundation modeling, marine resource delineation, and nautical charting. While this ubiquity makes the generation...
Climate change has pervasive impacts on Earth’s diverse ecosystems. Observed and projected effects that impact coastal environments pose unique challenges. Coastal regions provide numerous ecosystem services (e.g., fisheries, nursery habitats, erosion control, and water filtering and detoxification), house 40% of the US population, and contribute to 58% of the national...