EPANext-day AQI forecasts for ozone and PM2.5 issued by state and local air quality agencies across the United States, published daily through the AirNow forecast system.
NOAA
NOAA HYSPLIT Trajectory Model
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HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) is NOAA's workhorse atmospheric transport model, used to compute the paths of air parcels and the atmospheric transport, dispersion, chemical transformation, and deposition of pollutants and particles. The model can compute both forward trajectories (where will this air go?) and backward trajectories (where did this air come from?).
HYSPLIT is used by researchers, forecasters, and emergency responders worldwide to trace the origins and pathways of wildfire smoke, dust storms, volcanic ash, and industrial pollutants. The model runs on NOAA's GDAS, EDAS, and NARR meteorological archives and is freely available through the NOAA ARL READY system.
Learn more
Documentation, algorithm details, and background reading for HYSPLIT.
Download data
Access HYSPLIT through the provider portal or download it directly.
Tutorials
Self-paced tutorials to help you get started with HYSPLIT.
Getting started with HYSPLIT
An introduction to the HYSPLIT dataset — what it measures, how it is produced, and when to use it.
Accessing and downloading HYSPLIT dataFind, subset, and download HYSPLIT data, with tips for common file formats and access tools.
Exploring HYSPLIT in the AIR4US visualization toolLoad HYSPLIT layers in the AIR4US visualization tool and interpret them alongside other air quality data.
Cite this dataset
NOAA ARL. NOAA HYSPLIT Trajectory Model. Accessed via the AIR4US Portal, https://www.ready.noaa.gov/HYSPLIT.php.
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