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Community Multiscale Air Quality Modeling System (CMAQ)

CMAQ Inputs and Test Case Data

Benchmark Test Case Downloads

Input and benchmark comparison data to test the build of both the base CMAQ and the WRF-CMAQ models are  available from the CMAS Center Data Warehouse Google Drive and EPA's anonymous FTP server.  The benchmark data set is a 2 day CMAQ simulation (July 1 -2, 2016) over the Southeast U.S. (80 row x 100 col) using a 12km grid size.  An annual set of model inputs for 2016 for the continental U.S. (CONUS) are also available to download.

The following links exit the site Exit

File type File name (DOI or Download Link) File Size
CMAQv5.3.2 Base Model Southeast Benchmark (including reference output for CMAQ-ISAM and WRFv4.1.1-CMAQv5.3.2)
Two day input data CMAQv5.3.2_Benchmark_2Day_Input.tar.gz (doi:10.15139/S3/IQVABD | Anonymous FTP Link) 6.3Gb
Two day output data CMAQv5.3.2_Benchmark_2Day_Output_[Optimized/Debug].tar.gz (doi:10.15139/S3/PDE4SS |Anonymous FTP Link) 2.5Gb
CMAQv5.3 Base Model CONUS Input Data
2016 input data Input data is organized into 5 folders: surface, misc, met, icbc, emis (doi:10.15139/S3/MHNUNE)  
Single day input data CMAQv5.2_Benchmark_SingleDay_Input_09_12_2017.tar.gz (Google Drive Link) 1.9Gb
Single day output data CMAQv5.2_DDM-3D_Benchmark_SingleDay_Output_09_12_2017.tar.gz (Google Drive Link) 7.6Gb
Multi-day input data CMAQv5.2_Benchmark_MultiDay_Input_09_05_2017.tar.gz    (Google Drive Link) 16Gb
Multi-day output data CMAQv5.2_DDM-3D_Benchmark_MultiDay_Output_09_12_2017.tar.gz (Google Drive Link) 108GB
two day input data CMAQv5.3.2_Benchmark_2Day_Input.tar.gz (Google Drive Link Anonymous FTP Link) 6.3 GB
two day output data WRFv4.1.1-CMAQv5.3.2_*_2day.tar.gz (Google Drive Link | Anonymous FTP Link) 4 GB

Additional Input Data

Use the following links to download additional input data depending on the needs of your CMAQ simulation.

The National Emissions Inventory (NEI) Modeling Platforms

The National Emissions Inventory (NEI) is a comprehensive and detailed estimate of air emissions of criteria pollutants, criteria precursors, and hazardous air pollutants from air emissions sources. The NEI is released every three years based primarily upon data provided by State, Local, and Tribal air agencies for sources in their jurisdictions and supplemented by data developed by the US EPA.

The NEI modeling platforms are the full set of emissions inventories, other data files, software tools, and scripts that process the emissions into the form needed for air quality modeling. Each emissions modeling platform supports air quality modeling of a historic year and one or more later years. Each platform relies on a version of the NEI for most of its data, although some adjustments are made, including augmenting with additional data and temporal and spatial tuning to support air quality modeling.

Fire Emissions

Fire emissions require fire location, burned areas, and detailed fuel load information.  Examples of where to find these types of datasets are proved below.  All of these information sources can be used to estimate fire emissions. An example of a tool that can be used to generate fire emissions is the US Forest Service BlueSky modeling framework.  BlueSky modularly links a variety of independent models of fire information, fuel loading, fire consumption, fire emissions, and smoke dispersion.  SmartFire Version 2 is one component of the BlueSky modeling framework used to reconcile fire information from multiple sources.  Using these tools and estimating fire emissions can be quite complex so datasets of fire emissions have been created for the community. Examples of these datasets is the Fire Inventory from the National Center for Atmospheric Research or the Global Fire Emissions Database.

Processing Spatial Data 

Information on how to create consistent geospatial data for CMAQ inputs using the Spatial Allocator (SA) utility.