Deeper understanding of relationships between flow in river sand various hydrologic elements such as rainfall, land use, and soil type is imperative to solve water related problems like droughts and floods. Advanced computer models are becoming essential in helping us understand such relationships. However, preparing such models requires huge investment of time and resources, much of which are concentrated on acquisition and curation of data. This work introduces agree and open source web Application (web App) that provides researchers with simplified access to hydrological data and modeling functionality. The web App helps in the creation of both hydrologic models, and climatic and geographic data. Free and open source platforms such as Tethys and Hydro Share were used in the development of the web Apia physics based model called TOPographic Kinematic APproximation and Integration (TOPKAPI) was used as the driving use case for which a complete hydrologic modeling service was developed to demonstrate the approach. The final product is a complete modeling system accessible through the web to create hydrologic data and run a hydrologic model for a watershed of interest. An additional model, TOPNET, was incorporated to demonstrate the generality of the approach and capability for adding other models into the framework.

HydroShare is a collaborative online system being developed by the Consortium of Universities for the Advancement of Hydrologic Science Inc. (CUAHSI) with the goal of facilitating the dissemination, visualization, and publishing of hydrologic data and models. External web applications serve a key role in extending HydroShare's capabilities, so robust application programming interfaces (APIs) are a vital component of HydroShare's architecture. Hydrologic data stored on HydroShare are defined by a data type, and much of these data are either geospatial or time series data. Although HydroShare's API provides ways to upload and download files, as well as access certain metadata, it does not currently provide GIS services defined by the Open Geospatial Consortium, or Hydrologic Information System (HIS) services developed by CUAHSI. The absence of these services severely limits the capabilities of HydroShare apps while also increasing the development time and complexity of apps that are developed.To help alleviate this disconnect between HydroShare and HydroShare apps, I have developed a system which helps extend HydroShare's data service capabilities using GeoServer and a Water Data Server to expose GIS and HIS data services for HydroShare content. With this system in place, HydroShare apps have much better access to HydroShare content, allowing them to be developed in less time, and provide much more powerful visualization, access, and analysis services to HydroShare users.

There has been a growing recognition in recent years of the need for a standardized means for sharing water data on the web. One response to this need was the development of the Consortium of Universities for the Advancement of Hydrologic Science (CUAHSI) Hydrologic Information System (HIS) and its accompanying WaterOneFlow and WaterML protocols. To date, the primary means for accessing data shared using these protocols has been limited to the Microsoft Windows HydroDesktop software, the WaterML R package, and the web based CUAHSI HydroClient which serves as an access point to the CUAHSI HIS database. We recognized the need for a new web-based tool for accessing data from any system that supports WaterOneFlow web services and WaterML and that could be regionally customizable, giving access to the most locally relevant portions of the HIS database, and providing a means for international government agencies, research teams, and others to make use of the accompanying protocols on a locally managed web application. To fill this need, we developed the open source, lightweight, installable web application, Water Data Explorer (WDE) which supports any WaterOneFlow service and can be customized for different regions containing WaterOneFlow web services. The WDE supports data discovery, data visualization, and data download for the selected WaterOneFlow services. The WDE's structure consist of WaterOneFlow catalogs, servers, and individual measurement stations. The WDE provides a different User Interface for administrators and regular users. A server administrator can specify which datasets an individual instance of the WDE supports so that end users of the application can access data from the specified datasets. We modularized the core WaterOneFlow access code into a new open-source Python package called "Pywaterml" which provides the methods used by WDE to discover, visualize, and download data. This thesis presents the design and development of the WDE and the associated Pywaterml package, which was done in partnership with end-users from the WMO and was done in an iterative design-build process. We present two case studies which involve data discovery and visualization from the CUAHSI HIS and WMO Hydrological Observing System (WHOS). Both case studies demonstrate the regional customization of the WDE which allows creation of different custom versions of the same application to meet specific end-user needs. The WDE data discovery in both case studies focuses on discovering the different sites contained in a WaterOneFlow web service, and ontology-based data discovery for the different concept variables in each web service. The data visualization we present, focuses on the time series observation for the different sites in each system. Finally, we tested data downloading in data discovery and visualization by downloading the information of each site to the WDE database and allowing the user to download the time series data.

Earth observation data is increasingly ubiquitous, easily accessible, freely available, and generally usable due to improvements in software, data standards, network infrastructure, and national policies. As a result, greater opportunities arise for using these data in a wider field of application including decision support for local and regional environmental and water resources management efforts. In parts of the world where in situ data are less readily available, global Earth observation data used in such decision support tools can be a boon to underfunded government and private water management agencies. The United Nations Group on Earth Observations Global Water Sustainability initiative (GEOGloWS) works to coordinate such solutions, bringing global water management capabilities to local decision makers. The recent development and deployment of a global hydrologic modelling system based on historical simulations and daily ensemble forecasts from the European Centre for Medium-Range Weather Forecasts (ECMWF) using Earth observations and streamflow routing on every river of the world results in a highly informative and potentially transformative dataset for users at local scales. However, for this data to reach its full potential at the local level, it needs to be subsetted at a regional or local scale, presented in a local geographic context, and interpreted in terms of local water management challenges. Furthermore, this subsetting allows for customization to support the way information is used and the kinds of decisions that are made. This paper presents the design, development, and experimental testing of the GEOGloWS HydroViewer, which is an open source, web-based software that effectively localizes global ECMWF forecasts to meet the needs of water managers and decision makers through subsetting the mapping and modelling services and supporting other customization as needed. The unique Software-as-a-Service (SaaS) deployment method, developed and tested here, allows for individual water management agencies to automatically generate custom HydroViewer applications that can be managed and/or customized depending on need and capacity in-country without reliance on external software and capacity, removing typical interdependence relationships that often define technology transfer to developing countries.

Water quality data collection, storage, and access is a difficult task and significant work has gone into methods to store and disseminate these data. We present a tool to disseminate research in a simple method that does not replace but extends and leverages these tools. In the United States, the federal government maintains two systems to fill that role for hydrological data: the U.S. Geological Survey (USGS) National Water Information System (NWIS) and the U.S. Environmental Protection Agency (EPA) Storage and Retrieval System (STORET), since superseded by the Water Quality Portal (WQP). The Consortium of the Universities for the Advancement of Hydrologic Science, Inc (CUAHSI) has developed the Hydrologic Information System (HIS) to standardize search and discovery of these data as well as other observational time series datasets. Additionally, CUAHSI developed and maintains HydroShare.org as a web portal for researchers to store and share hydrology data in a variety of formats including spatial geographic information system data. We present the Tethys Platform based Water Quality Data Viewer (WQDV) web application that uses these systems to provide researchers and local monitoring organizations with a simple method to archive, view, analyze, and distribute water quality data. WQDV provides an archive for non-official or preliminary research data and access to those data that have been collected but need to be distributed prior to review or inclusion in the state database. WQDV can also accept subsets of data downloaded from other sources, such as the EPA WQP. WQDV helps users understand what local data are available and how they relate to the data in larger databases. WQDV presents data in spatial (maps) and temporal (time series graphs) forms to help the users analyze and potentially screen the data sources before export for additional analysis. WQDV provides a convenient method for interim data to be widely disseminated and easily accessible in the context of a subset of official data. We present WQDV using a case study of data from Utah Lake, Utah, United States of America.

Hydrologic research is increasingly data and computationally intensive, and often involves hydrologic model simulation and collaboration among researchers. With the development of cyberinfrastructure, researchers are able to improve the efficiency, impact, and effectiveness of their research by utilizing online data sharing and hydrologic modeling functionality. However, further efforts are still in need to improve the capability of cyberinfrastructure to serve the hydrologic science community. This dissertation first presents the evaluation of a physically based snowmelt model as an alternative to a temperature index model to improve operational water supply forecasts in the Colorado River Basin. Then it presents the design of the functionality to share multidimensional space-time data in the HydroShare hydrologic information system. It then describes a web application developed to facilitate input preparation and model execution of a snowmelt model and the storage of these results in HydroShare. The snowmelt model evaluation provided use cases to evaluate the cyberinfrastructure elements developed. This research explored a new approach to advance operational water supply forecasts and provided potential solutions for the challenges associated with the design and implementation of cyberinfrastructure for hydrologic data sharing and modeling.

This paper documents the design and creation of an App Library for HydroShare water resources data and software discovery and sharing system. This App Library was developed to simplify the discovery process for using environmental web applications and to lower hosting requirements for such a repository. To accomplish this goal, I created the HydroShare App Library as a standalone web application using the React JavaScript framework. The App Library application uses the existing HydroShare resource connectors to allow the registration of all web applications within the App Library without having external software requirements. This allows the HydroShare App Library to be a centralized location for web app developers to register their tools and models using their preferred software while allowing water resources managers, engineers, scientists, and decision-makers to find these tools in a single location. The developed HydroShare App Library allows the discovery of all web applications that are included in the HydroShare ecosystem and not just CUAHSI-owned web apps. This is done by using a dynamic table with React that automatically updates the user interface without having to reload entire pages. This approach allows this web app to reduce processing for the App Library by only rendering web app entries that are relevant to the current user. This allows the App Library to grow and continue to be effective as more web applications are registered in HydroShare and are discoverable within the App Library.