Eastern Geographic Science Center
Description of Current Projects
Dynamic Surface Water Extent
Principal Investigator: John W. Jones, Ph.D., U.S. Geological Survey, Eastern Geographic Science Center
The Science Issue and Relevance
How do land inundation changes over time affect and reflect climate, hydrology, biology, geology and natural resource management? Public release of the Landsat Archive and the proliferation of government and commercial remote sensing systems are providing an unprecedented opportunity to address this question by measuring and tracking the dynamics of surface water extent from local to global scales. However, the development of techniques to derive and apply surface water dynamics information from remote sensed data have not kept pace with government and private industry capacity to generate and distribute data from both passive and active sensing systems. Research is needed to design and test methods of data fusion and information extraction to provide high-spatial and temporal resolution information on surface water dynamics. The goal of this project is to develop, document and implement innovative techniques to understand surface water dynamics at high spatial and temporal resolutions.
Methodology for Addressing the Issue
Because of the lengthy record and expansive areal coverage provided by the Landsat Archive, the initial focus of the project is the development of a Landsat-based Dynamic Surface Water Extent (DSWE) science product, one of several Essential Climate Variables being developed from the Landsat archive as science products. Every clear Landsat pixel collected over a study area since the launch of the first Thematic Mapper instrument is tested for the presence or absence of surface water. Study sites are selected to provide the range of conditions needed to robustly test surface water dynamics science products derived from remote sensing. Sample DSWE outputs are rapidly compared with existing geodatabases on hydrography and wetlands. For a subset of the study sites, multi-sensor databases are developed and in situ data are gathered from collaborators or project team members to provide non-Landsat data for model development and testing. DSWE uncertainty is measured and documented through comparison with these independent data. Also, the products are used in collaborative science and water resource management to assess and demonstrate their utility.
Even higher spatial and temporal resolution DSWE products will be developed through exploitation and fusion of all available remote sensed data.
Key Words: Hydrology, uncertainty assessment, surface water dynamics, Essential Climate Variables, Landsat science products, water resource management
John W. Jones, PhD