• UW Environmental Modelling and Analysis Group
  A collection of researchers dedicated to improving the science and practice of simulation modelling of the natural environment.
• BASINS - Better Assessment Science Integrating Point & Nonpoint Sources
  "A multi-purpose environmental analysis system that integrates a geographical information system (GIS), national watershed data, and state-of-the-art environmental assessment and modeling tools into one convenient package."
• CCA - Common Component Architecture
  "A component architecture defining standards necessary for the interoperation of components developed in the context of different frameworks."
• CCSM - Community Climate System Model
  "A fully-coupled, global climate model that...includes models of the atmosphere, land surface, ocean, and sea ice."
• CHyMP - Community Hydrologic Modeling Platform
  "Common simulation software designed to serve the diverse needs of [the hydrology] community, and to be advanced through contributions from the community."
• CHPS - Community Hydrologic Prediction System
  "A software infrastructure, built on standard software packages and protocols, and open data modeling standards... provides the basis from which new and existing hydraulic and hydrologic models and data can be shared within a broader hydrologic community. "
• CSDMS - Community Surface Dynamics Modeling System
  "Integrated software modules that predict the movement of fluids, and the flux (production, erosion, transport, and deposition) of sediment and solutes in landscapes and their sedimentary basins."
• CSTMS - Community/Coastal Sediment Transport Modeling System
  "An open-source model that couples hydrodynamics (circulation and waves), sediment transport, and morphodynamics."
• ESMF - Earth System Modeling Framework
  "Defines an architecture for composing complex, coupled modeling systems and includes data structures and utilities for developing individual models."
• FRAMES - Framework for Risk Analysis of Multimedia Environmental Systems
  A software infrastructure for integrating models and modeling tools.
• HydroGeoSphere
  "A 3D model for simulating flow and contaminant transport in integrated surface/subsurface flow systems."
• InHM - Integrated Hydrology Model
  "Integrates surface and subsurface flow and transport processes in one coherent framework, eliminating iterative coupling between surface and subsurface models through the use of physically-based first-order flux relationships." - a precursor of HydroGeoSphere
• MENTOR - Modelling Environmental for Total Risk Studies
  "An evolving open modeling support system which can also be described as an expandable computational toolbox."
• MESH - Modélisation Environmentale Communautaire, Surface and Hydrology
  A component of Environment Canada's community environmental modelling system (MEC), MESH couples land surface and hydrology models and is designed for regional hydrological modeling.
• MIMES - Multi-scale Integrated Models of Ecosystem Services
  "A suite of models that enables understanding of the contributions of ecosystem services by quantifying the effects of varying environmental conditions derived from land use change."
• OMS - Object Modelling System
  "A library of alternate science and database modules, which facilitates the assembly of a modeling package, tailored to the problem, data constraints, and scale of application."
• OpenMI - Open Modelling Interface
  "Provides a standard interface, which allows models to exchange data with each other and other modelling tools on a time step by time step basis as they run."
• ParFlow - Parallel Flow Simulator
  "An integrated, parallel watershed model that makes use of high-performance computing to simulate surface and subsurface fluid flow...ParFlow has also been fully-coupled to a land surface model (CLM) and to a mesoscale atmospheric model (ARPS)."
• PIHM - Penn State Integrated Hydrologic Modeling System
  "A multiprocess, multi-scale hydrologic model where the major hydrological processes are fully coupled using the semi-discrete finite volume method."
• PRISM - Partnership for Research Infrastructures in earth Systems Modelling
  "Provides the Earth System Modelling community with a forum to promote shared software infrastructure tools."
• RHESSys - Regional Hydro-Ecologic Simulation System
  "A GIS-based, hydro-ecological modeling framework designed to simulate carbon, water and nutrient fluxes."
• tRIBS - TIN-based Real-time Integrated Basin Simulator
  "A physically-based, distributed hydrologic model ...that emphasizes the dynamic relationship between a partially saturated vadose zone and the land surface response to the continuous storm and interstorm cycle."