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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 and the coupled models are  available from the CMAS Center Software Clearinghouse. From https://www.cmascenter.org, select Download -> Software -> CMAQ and choose version 5.2.​  A single day and a two-week benchmark case are available for the CMAQv5.2 base model and the CMAQv5.2 DDM-3D version.

File type File name File Size
CMAQv5.2 Base Model
Single day input data CMAQv5.2_Benchmark_SingleDay_Input_09_05_2017.tar.gz 1.9Gb
Single day output data CMAQv5.2_Benchmark_SingleDay_Output_09_05_2017.tar.gz 7.7Gb
Multi-day input data CMAQv5.2_Benchmark_MultiDay_Input_09_05_2017.tar.gz 16Gb
Multi-day output data CMAQv5.2_Benchmark_MultiDay_Output_09_05_2017.tar.gz 108Gb
CMAQv5.2 DDM-3D
Single day input data CMAQv5.2_Benchmark_SingleDay_Input_09_05_2017.tar.gz (same as the base model) 1.9Gb
Single day output data CMAQv5.2_DDM-3D_Benchmark_SingleDay_Output_09_12_2017.tar.gz  7.6Gb
Multi-day input data CMAQv5.2_Benchmark_MultiDay_Input_09_05_2017.tar.gz    (same as the base model) 16Gb
Multi-day output data CMAQv5.2_DDM-3D_Benchmark_MultiDay_Output_09_12_2017.tar.gz  108GB
Coupled WRF3.8-CMAQ5.2
Single day input data WRFv3.8_CMAQv5.2_Input.tar.gz 1.8Gb
Single day output data WRFv3.8_CMAQv5.2_Output.tar.gz 26.1Gb

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

Lightning Flash Count Data for Estimating NO Production 

The Community Modeling and Analysis System (CMAS) center hosts monthly 12-km resolution cloud-to-ground (CG) flash counts over North America for 2002-2014 on the standard 12-km United States CMAQ grid. These data were created using National Lightning Detection Network (NLDN) raw flash data from Vaisala. These data can be used to simulate lightning NO emissions in CMAQv5.0 and higher.

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.

Wind-Blown Dust Emissions

The windblown dust module in CMAQv5.2 uses Fraction of Photosynthetically Active Radiation (FPAR) from MODIS as a surrogate to vegetation fraction. These data should be provided by the user as an input to the CCTM. The 1-km resolution gridded data are updated every 8 days and can be downloaded from the USGS Land Processes Distributed Active Archive Center (LPDAAC). These data should be smoothed and gap-filled data before use with the CCTM. Monthly global MODIS FPAR and leaf area index (LAI) data averaged over 10 years (2001-2010) are available as part of WRF Preprocessing System (WPS). A procedure to obtain and process the LPDAAC daily gridded FPAR and LAI data for CMAQ is described in the Tuorials section of the CMAQ repository on GitHub: Wind-Blown Dust Input Data TutorialExit

Processing Spatial Data 

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