The flow of water in a river channel redistributes various materials, including organisms and pollutants, through a process called dispersion. Understanding this mechanism is critical for applications ranging from species conservation to hazardous waste management. Tracer tests with a visible dye are often used to study dispersion, typically by measuring dye concentration directly in the field at a few fixed locations.
High-resolution hydrographic mapping, which provides essential data for flood mitigation and planning, has been completed on thirteen, 12-digit hydrologic units near Sioux Falls in southeastern South Dakota. A lidar-derived digital elevation model was processed to include culvert locations into the modeled drainage network.
Archival aerial stereo-photographs are a source of information that can be used to create historical topography models for rapidly changing landscapes. Researchers completed a pilot study in Malakoff Diggins State Historic Park (MDSHP), which was once the largest hydraulic mine (1.6 square kilometers) in the Sierra Nevada of California. Legacy impacts in these mined landscapes include remnant steep exposures of highly erodible Eocene-aged auriferous sediments.
The National Map Corps (TNMCorps), a crowdsourced mapping project, relies on volunteers to assist the USGS National Geospatial Program by collecting and editing man-made structures data for The National Map. Through their participation, volunteers make important contributions to the USGS’s ability to provide the Nation with accurate mapping information.
The USGS National Land Imaging Program (NLIP) has built a long-term capacity to collect and analyze land imaging user requirements to advance the Nation’s operational and science objectives and better serve the land imaging community. The USGS documents the land imaging requirements of U.S.
The goal of the USGS 3D Elevation Program (3DEP) is to complete nationwide coverage of lidar data for the conterminous United States, Hawaii, and the U.S. territories and interferometric synthetic aperture radar (IfSAR) for Alaska within 8 years—that is, by 2023--contingent upon sufficient funding.
The USGS 3D Elevation Program (3DEP) is managing the acquisition of lidar data across the Nation for high-resolution mapping of the land surface, which is useful for multiple applications. While lidar data are available for many Department of the Interior (as well as other Federal) lands in the U.S., these data are underutilized for vegetation analyses, partly due to the lack of local personnel and software capable of processing and analyzing lidar data.
The USGS is leading a 3D Elevation Program (3DEP) effort to coordinate with other Federal agency partners and the State of Alaska to acquire new Alaska elevation data statewide using remote sensing techniques. Under its Geospatial Products and Services Contract (GPSC), the USGS is contracting with vendors to acquire 5-meter (m) resolution elevation data using Interferometric Synthetic Aperture Radar (InSAR) sensors flown on aircraft.
The potential for gravitational and explosion-driven collapse is one of the greatest hazards of lava dome eruptions. Topographic modeling of active lava domes is useful for detecting changes that may influence collapse or explosive activity. It also provides constraints on the volume of potentially collapsible material, a key parameter of effective hazard assessment.
The lack of Pacific Islands topographic (land elevation) and bathymetric (water depth) information led Department of the Interior (DOI) researchers to use advanced remote sensing technologies to develop a topobathymetric digital elevation model (TBDEM) for Majuro Atoll, Republic of the Marshall Islands. With a maximum natural elevation of only 3 meters (m), Majuro Atoll is extremely vulnerable to changes in sea level, tsunamis, storm surge, and coastal flooding.