The World Hydrological Observing System (WHOS), operating under the World Meteorological Organization (WMO) Data Policy, serves as a global gateway for the standardized exchange of hydrological, meteorological, and climate-related environmental data. Designed to uphold principles of open access and transparency, WHOS eliminates the need for centralized data storage by dynamically linking users to original data providers—such as national hydrometeorological agencies, research institutions, and monitoring networks—through its advanced Discovery and Access Broker (DAB) technology. This middleware framework harmonizes disparate data formats and protocols (e.g., OGC WaterML 2.0, ISO metadata standards), enabling seamless interoperability across geographic and institutional boundaries. Users gain real-time access to critical datasets, including river discharge, groundwater levels, and precipitation trends, while adhering to strict Terms of Use that prohibit unauthorized commercial exploitation, mandate attribution to source agencies in publications or downstream services, and require acknowledgment of inherent risks (e.g., data latency, sensor inaccuracies).

This application demonstrates two projects developed by the University of Iowa Hydroinformatics Lab (UIHI Lab): HydroLang and HydroCompute. HydroLang is an open-source web framework designed for hydrology and water resources research. It offers JavaScript functions for various tasks, including retrieving and manipulating hydrologic data, performing statistical operations, generating graphical data representations, and mapping geospatial data. HydroCompute, on the other hand, is an open-source computational library geared towards hydrology and environmental sciences. It operates natively in web browsers and utilizes state-of-the-art computation standards to enable web applications to tap into the computational capabilities of the devices they run on. This includes leveraging multithreading with web workers, processing with GPUs, and running executables built in WebAssembly (WASM). This application serves as the solution for HydroCompute Case Study 3: Dashboard for Station Statistical Analysis tutorial. This tutorial was developed by the University of Iowa Hydroinformatics Lab for the 2023 CIROH Developer Conference.