A geotemporal framework for hydrologic analysis

The wealth of publicly available hydrologic data from observation networks, satellite-based sensors, global-scale modeling efforts, and digitized paper maps provide an excellent base-line of information for understanding hydrologic systems. It is difficult, however, to fuse this information into a holistic picture because there are many different formats and data models for storing, analyzing, and sharing such information. To address this problem, this research presents a prototype system for assembling local and remote data sources of various formats into a common geospatial-temporal (or simply geotemporal) framework for hydrologic analysis. Starting from the basic concept of geographic information science that space consists of entities and fields, new concepts are derived for representing hydrologic space: geospatial time series and hydrologic flux coupler. A class library named HydroObjects is created that uses these new concepts to extend GIS vii software for geotemporal visualization and processing of hydrologic data. The HydroObjects library provides interoperability between hydrology data because the attributes of an object can be populated from a variety of sources, formats, and data models. As a case study, geotemporal visualization and processing extensions developed through this research are used to perform and visualize a water budget for subwatersheds of the Neuse River Basin, North Carolina. The water budget calculations are performed with data directly ingested from remote hydrologic data bases through the internet and then processed locally to align in space and time. The case study is an example of how hydrologists can gain access to remote information, fuse these data sources into a single picture of the geotemporal watershed environment, and use the information to formulate and test hypotheses regarding the hydrologic cycle.