Marsh canopy structure indicators of leaf area index (LAI) and leaf angle distribution (LAD) were mapped yearly from 2009 to 2012 in the Barataria Bay, Louisiana, coastal region – an area severely impacted by the 2010 Deepwater Horizon (DWH) oil spill. The mapping relied on summer collections of NASA's UAVSAR polarimetric synthetic aperture radar (PolSAR) image data.
INSAR / SAR / Radar
An automated shoreline identification method was developed using standard image processing, geographic information system (GIS) techniques (https://woodshole.er.usgs.gov/project-pages/DSAS/version4/), and 2-m synthetic aperture radar (SAR) HH amplitude data. The development used five NASA Uninhabited Aerial Vehicle SAR (UAVSAR) images collected in summer and one in fall from 2009 to 2012.
Substantial loss of coastal wetland caused by the Deepwater Horizon (DWH) oil spill was documented for the first time in recent publications (http://onlinelibrary.wiley.com/doi/10.1002/2016GL070624/full). Those results demonstrated that the 2010 DWH oiling exacerbated wetland shoreline erosion, that erosion magnitude increased with oiling severity, and that oil-related erosion differed from storm-related shoreline erosion.
Remote-sensing-based maps of tidal marshes, both of their extents and carbon stocks, have the potential to play a key role in informing greenhouse gas inventories and implementing climate mitigation policies. Despite multiple efforts to map tidal marsh aboveground biomass regionally, differences in plant communities and site characteristics pose limitations for scaling to the national level.
Multiple agencies in the San Diego area have the responsibility to effectively manage the water supply in this arid, urban, densely populated, coastal basin in southern California. Recently, five additional groundwater production wells were constructed to increase the water supply; the new wells are scheduled to begin pumping in 2017. California’s Sustainable Groundwater Management Act of 2014 (SGMA) provides a framework to comprehensively measure and manage groundwater.
Nearly a quarter of California’s freshwater supply flows through the Sacramento-San Joaquin Delta, an area that comprises marshland and reclaimed land in the form of islands surrounded by levees. The Delta is of critical importance to the State’s water supply, contains prime agricultural resources, and functions as a vital estuarine ecosystem. Land-surface subsidence and levee instability within the Delta pose serious threats to meeting Federal, State, and local goals related to ecosystem restoration and land, water-resource, and flood-disaster management.
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-m resolution elevation data using Interferometric Synthetic Aperture Radar (InSAR) sensors flown on aircraft.
Monitoring streamflow from large, remote rivers like those in Alaska is costly and hazardous through conventional means. Therefore, the USGS is experimenting with methods to estimate Alaskan river streamflow through remote sensing. Current study areas include reaches on the Yukon, Tanana, and Chena Rivers.