Reference

Last updated on 2025-04-22 | Edit this page

Glossary

  • Modeling Terms
    • National Water Model (NWM)
      • Hydrologic model used operationally by NOAA’s National Weather Service to provide hydrologic predictions for over 3.4 million rivers and streams across the United States
    • Next Generation Water Resources Modeling Framework (NextGen)
      • An advancement of the NWM, a standards-based and model-agnostic modular set of software tools that applies the Basic Model Interface
    • NextGen in a Box (NGIAB)
      • An open-source, containerized solution that encapsulates the NextGen framework and essential modeling components into a self-contained, reproducible application
    • Data Preprocess
      • A tool to streamline data preparation for NextGen runs
    • Tools for Exploratory Evaluation in Hydrologic Research (TEEHR)
      • A Python-based package enabling iterative and explorative analysis of hydrologic model performance
    • Data Visualizer
      • A tool that provides a robust environment for geospatial and time series visualization of catchments and nexus points
    • Forcings
      • External inputs that drive a model
    • t-route
      • Channel routing model used in the NWM. t-route is used in NextGen.
    • Channel routing
      • Predicts the magnitude and shape of a hydrograph as water moves through waterways.
    • ngen
      • The NextGen model engine
    • Realization file
      • A file that configures models and the variables exchanged between them. For example, our realization files define which hydrologic model we are using, over what time period, and over which regions.
    • Hydrofabric
    • Conceptual Functional Equivalent (CFE) Model
      • A simplified conceptual rainfall-runoff model designed to be functionally equivalent to the NWM. This is an available model in NGIAB.
    • Rainfall-runoff model
      • Describes how rainfall is converted into runoff in a catchment, producing a hydrograph in response to a rainfall event
    • NoahOWP
      • Version of the Noah-MP land surface model used by NOAA’s Office of Water Prediction. This is an available model in NGIAB.
    • Land surface model
      • Describes the exchange of water and energy between the land surface and the atmosphere
    • Long short-term memory (LSTM) model
      • A type of recurrent neural network that excels at learning long-term dependencies in sequential data. This is an available model in NGIAB.
    • Error statistics
      • The difference between the true value and the modeled variable
    • Skill score
      • The accuracy of a model relative to a reference approach, like random chance or persistence
    • Persistence
      • A forecast that the future condition will be the same as the present condition
    • Uncertainty quantification
      • Estimation of uncertainty and errors in models
  • Computing Terms
    • Containerization
      • Encapsulating applications, their dependencies, and runtime environments into a single, portable unit to address compatibility issues and hardware variation challenges
    • Docker
      • A widely used containerization platform that provides a lightweight, portable, and scalable solution for software deployment
    • Singularity
      • A containerization platform for HPC environments
    • Basic Model Interface (BMI)
      • A standardized system designed to enhance interoperability between models and datasets
    • Tethys Platform
      • Platform for geospatial web app development
    • High-Performance Computing (HPC)
      • Systems with clusters of parallel processors that process data and perform calculations at high speeds
    • Job scheduler (e.g. SLURM/PBS/LSF)
      • A software that manages which tasks run where and when on an HPC system
    • Open-source
      • Software or data that is publicly accessible and can be redistributed or modified
    • Secure Shell (SSH)
      • Network protocol that provides secure remote access with encrypted connections
  • Hydrologic Terms
    • Catchment
      • Area from which precipitation collects and drains into an output point like a river or water body. Also known as a watershed
    • Streamflow
      • The flow of water in a channel, measured in units of volume/time (e.g. cubic meters per second (CMS), cubic feet per second (CFS)). Also known as discharge
    • Hydrologic model
      • A computer-based replication of the natural water cycle
    • CONUS (Continental United States)
      • Refers to the 48 contiguous states and D.C.
    • Surface runoff
      • Unconfined flow of water over the ground surface
    • Hydrologic signature
      • Quantitative metrics that define streamflow, such as maximum flow, baseflow, mean flow, or slope
    • Hydrograph
      • Graph that depicts streamflow at a specific location over time