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Looping plume
  • Get/Run the HYSPLIT Model - Download the PC or Mac version or run the model on the web. Registration may be required to access some portions of this page. Additional documentation on the HYSPLIT model and its meteorological data can also be found here.
  • HYSPLIT Basic Tutorial - Want to learn more about HYSPLIT and how to run the PC/Mac version? Then this online tutorial is the place to start as it will provide you with a good starting point for running the model appropriately.
  • HYSPLIT Forum - Have a question about HYSPLIT? Register for the HYSPLIT Forum and search for an answer to your question or ask the user community for ideas and answers to your specific application.
  • HYSPLIT Workshops - NOAA Air Resources Laboratory presents a PC/Mac HYSPLIT Workshop in the spring or early summer each year and follows the material found in the HYSPLIT Tutorial.
  • Volcanic Ash - Volcanic ash from an erupting volcano can seriously impact the aviation community. This section presents links to current and hypothetical eruptions within the Washington and Anchorage Volcanic Ash Advisor Center (VAAC) areas of responsibilty. Users can also run the HYSPLIT model for many volcanoes around the world.
  • Fukushima NPP Transfer Coefficient Matrix (TCM) - Previously computed HYSPLIT simulations of the Fukushima Daiichi nuclear power plant accident are used to calculate Cesium-137 and Iodine-131 air concentrations and depositions from user selected source term estimates. The TCM allows provides an easy method to view the impacts of source term estimates without having to rerun the model for each case.
  • Short-Range Ensemble Forecast (SREF) Dispersion Forecasts - The NOAA National Centers for Environmental Prediction (NCEP) run a series of model forecasts called the Short-Range Ensemble Forecasting (SREF) system to provide an estimate of the variability of a single forecast. ARL is experimenting with using the SREF to provide an estimate of the variability one might expect in the dispersion forecast due to variations in the meteorology used by the model. The source location may vary.
  • Gaussian Plume Model - A simple model that was once considered the standard dispersion model for routine calculations is called the Gaussian plume model because it assumes the air pollutant dispersion has a Gaussian distribution (normal probability distribution). It assumes a constant wind direction and speed and uniform terrain, which limits its applicability to many atmospheric dispersion problems especially cases where the meteorology is changing and for calculations distant from the source location. It is still used by some regulatory agencies due to its simplicity. A simple version of the Gaussian plume model is provided here only to demonstrate its functionality and should not be used for most transport and dispersion simulations. HYSPLIT is a better choice if looking to use a model to calculate transport and dispersion.
  • Balloon Flight Forecasting Tools - A tool for manned balloon flight planning has been developed that allows the user to visualize the potential flow combinations from up to three different starting heights, multiple times along the flight track. This tool uses the HYSPLIT model trajectories to determine where a balloon might travel if the height of the balloon is changed along the flight path and can help "steer" a balloon to a particular location or avoid a location such as calm winds.
Modified: October 17, 2016
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