Community Modeling and Analysis System

CMAS Webinars

The CMAS Center hosts regular webinars about important air quality-related topics as a way to keep the CMAS community up-to-date and informed. Webinar topics will range from introductions of new model releases to best practices to advanced modeling techniques. All seminars will be free and open to the public and will feature a 20-30 minute presentation followed by a question and answer session.

How to Connect

CMAS webinars will use the Zoom platform. If you have not connected to a Zoom meeting on your browser before, you will need to install a plugin when you connect. If you'd like to test your system prior to the start of the webinar, visit the Zoom Test Meeting to view system requirements and get set up.

If you are getting set up as the meeting starts, after you start the Zoom client, you may be asked for the event number. The event number is listed for each event. Or, you can return to this page and click the Join button again.

Linux users: Check out their Linux Install page

Have A Webinar Topic?

If you'd like to suggest a topic for a webinar, or if you would be willing to give a webinar presentation on a topic that would be of general interest to the CMAS community, please contact CMAS by email at



  • June 25, 2024. 1:00 PM (Eastern):

    Registration is required.
    Event Number: 925 7530 3291

    Use of NOAA's Global Forecast System Data in the Cloud for Community Air Quality Modeling Register!

    Presenter: Patrick Campbell, George Mason University

    Here we describe the novel NOAA-EPA Atmosphere-Chemistry Coupler (NACC) in the cloud ("NACC-Cloud") product ( NACC-Cloud on-demand processes NOAA's operational Global Forecast System version 16 (GFSv16) data, and outputs model-ready meteorological files needed for the widely used Community Multiscale Air Quality (CMAQ) model for any regional domain in the world. NACC is adapted from the U.S. EPA's Meteorology-Chemistry Interface Processor version 5 (MCIPv5), and was used as the primary model coupler for the operational National Air Quality Forecasting Capability (NAQFC). NACC-Cloud provides a web-based interface that can readily be used in the air quality modeling community for GFS-driven CMAQ applications. All of the NACC-Cloud development is based on the Amazon Web Services (AWS)-High Performance Computing (HPC) platform, specifically the AWS ParallelCluster v3.0. The main topics described in our presentation include 1) background on the GFSv16 and NACC software, 2) AWS-HPC environment and GFSv16 data in the cloud, 3) development and demonstration of the NACC-Cloud interface for the community, 4) examples of current applications of NACC-Cloud, and 5) future opportunities.


  • August 24, 2023. 1:00 PM (Eastern): [Download Slides | Watch Recording]

    Running CMAQ 5.4 on AWS

    Presenter: Liz Adams, UNC Institute for the Environment/CMAS

    This presentation will step through an online tutorial for running CMAQv5.4 on AWS HPC Cloud Services with a demonstration on how to create a ParallelCluster and run the 12US1 CMAQ benchmark case on multiple compute nodes. There will be time for discussion about benchmark timings and different costs for using different instance types.
  • February 22, 2023. 1:00 PM (Eastern): [Download Slides | Watch Recording]

    Event Number: 918 6027 6608

    CMAQv5.4 Diagnostics, Tools, and Instrumented Models

    Presenters: Ben Murphy and Sergey Napelenok, U.S. E.P.A

    CMAQv5.4 includes compelling science updates and exciting new features designed to improve the tools you have used before and introduce options to streamline your workflow, enhance transparency, and avoid potential errors. The Integrated Source Apportionment Method (ISAM) and the Decoupled Direct Method in 3D (DDM-3D) have both been fully integrated into the CMAQ code and are now released together in the same package as the base model. DDM-3D is largely unchanged in this release from the user perspective, although it has gone through substantial code improvements to be better compatible with the base code. ISAM now considers all fine and coarse particulate matter species and has been expanded to include additional flexibility on how apportionment is handled for various applications. Diagnostic output for the Detailed Emission Scaling, Isolation, and Diagnostics (DESID) emissions processor has been refined to a format that is equivalent to the inputs provided to CMAQ, allowing for more straight-forward analysis.

    Several new tools will also be discussed. The Explicit and Lumped CMAQ Model Output (ELMO) module has been introduced to calculate key metrics like PM2.5 mass online, thereby streamlining the post-processing workflow and saving storage space for outputs. The Autochem utility provides a turnkey method for generating new reaction mechanism source code from user modifications to the mechanism definition file or the chemical species namelists. Finally, a new Budget calculation tool tabulates domain-wide chemically-resolved production and loss rates for every model process and outputs them to a human-readable text file. This addition supports both data quality assurance as well as deeper scientific understanding of the total impact of individual chemical and physical processes on pollutants of interest. The talk will cover the scope and purpose of each of these advances, demonstrate configuration options, and provide links to helpful tutorials and other resources.


  • July 8, 2020. 2:00 PM (Eastern): [Download Slides | Watch Recording]

    Event Number: 984 3565 5270

    Challenges in using the SMOKE-CMAQ modeling system in South America: case studies in urban Brazilian cities

    Presenters: Professor Taciana Toledo de Almeida Albuquerque and Rizzieri Pedruzzi, Department of Sanitary and Environmental Engineering - Federal University of Minas Gerais, UFMG, Brazil

    In recent years, significant advances have been made in techniques used to estimate ambient air pollution levels and identify emission sources. In this way, Air Quality Models (AQMs) are becoming an important tool to assist policymakers in environmental agencies around the world. Concerning the SMOKE-CMAQ modeling system, several recent applications to different parts of the world are seen in the literature. Nevertheless, in the scenario of critical urban areas in South America, as Sao Paulo, Bogota, Santiago, among others, these studies are limited. Although SMOKE-CMAQ uses independent modules to make modifications and adaptations to the user's needs more straightforward, it requires local input data from several sources like land surface data, meteorology, boundary conditions, and emissions inventories (that require additional ancillary information for chemical speciation, temporal and spatial allocation) for the region of interest. Still, these data are mostly unavailable for the South American community, and often do not exist. Additionally, processing all of these models requires several skills, which limits the use of these tools. This talk will discuss the main challenges and limitations of using SMOKE-CMAQ models in urban Brazilian cities.
  • June 11, 2020. 2:00 PM (Eastern): [Download Slides | Watch Recording]

    Event Number: 988 8772 8595

    Global Sources of Anthropogenic Pollution in Multiscale CMAQ

    Presenter: Barron H. Henderson, U.S. E.P.A

    Air quality management practices often focus on local sources to address local air pollution problems. However, global research teams have long highlighted the importance of understanding the global contributions to local pollution. The US EPA Ozone Policy Assessment for the 2015 National Air Quality Standard for ozone highlights the role of background ozone, which includes natural and anthropogenic international sources. The current draft Ozone Policy Assessment similarly quantifies the role of background. This talk will discuss a recent large-scale model application study, the model evaluation, and the attribution of ozone to global emission sources.


  • December 18, 2019. 2:00 PM (Eastern): [Download Slides | Watch Recording]

    Event Number: 652-565-875

    An Introduction to Reduced-Complexity Models for Air Quality

    Presenter: Prof. Peter Adams, Carnegie Mellon University

    Chemical transport models (CTMs) are the gold standard for predicting how changing emissions will influence future air quality. However, they are computationally intensive, meaning that only a limited number of scenarios can be simulated in detail. Furthermore, they require considerable expertise, limiting the communities of researchers that can assess how emissions changes will affect ambient concentrations of air pollutants and human health. Reduced-Complexity Models (RCMs) fill this gap by providing tools that are better suitable for screening and uncertainty analyses and useable by policy and energy systems analysts that lack resources and expertise to use CTMs.

    This training will provide an introduction to three RCMs now publicly available for air quality assessments: APEEP, EASIUR, and InMAP. We will summarize the inner workings and assumptions in each of these models. We will demonstrate where to obtain these models, introduce how to use them, including how to adjust assumptions about dose-response and economic valuation. An intercomparison of the results of the models will be summarized.
  • November 12, 2019. 2:00 PM (Eastern): [Download Slides | Watch Recording]

    Event Number: 862-765-866

    What is new in AMET V1.4

    Presenters: Wyat Appel and Robert Gilliam, Atmospheric and Environmental Systems Modeling Division in EPA's Office of Research and Development (ORD)

    The Atmospheric Model Evaluation Tool (AMET) (Appel et al., 2011) is a suite of software designed to facilitate the analysis and evaluation of meteorological (e.g. WRF, MPAS) and air quality models (e.g. CMAQ, CAMx). AMET pairs model output with corresponding observed values for a variety of regional and global meteorological and air quality networks. These paired model/observations are then used to generate summary statistics and graphically analyze the model's performance using analysis scripts provided in AMET.

    A new version of AMET (version 1.4) was released in August 2019 containing a number of updates from the previous version (1.3). Some of these updates include:
    • Simplified process for adding new AQ networks/species
    • New interactive HTML R plots using the leaflet and dyGraphs R packages
    • Added support for global TOAR and NOAA ESRL networks
    • Ability to process and analyze AQ data without the database present
    • Improved batch scripting for AQ analysis
    • New WRF/MPAS upper-air rawinsonde, surface shortwave radiation, and PRISM rainfall analyses
    • New 2-m moisture time series comparison with RH
    • Site metadata improved to include state and elevation
    • Improve speed of database population for met data

    This webinar will present an overview of AMET and discuss some of the more important updates in the latest version of the tool. Very brief tutorials on the AQ and MET projects in AMET will also be presented, particularly focusing on those aspects of the tool that have changed from the previous version.
  • October 8, 2019. 2:00 PM (Eastern): [Download Slides | Watch Recording]

    Event Number: 525-865-401

    CMAQv5.3: Enhanced Capabilities to Analyze Emissions Scenarios

    Presenters: Rohit Mathur, Ben Murphy, Sergey Napelenok, Kristen Foley

    EPA's Office of Research and Development will walk through several of the enhanced features included with the recent v5.3 release of the Community Multiscale Air Quality Model (CMAQ).

    Topics to be covered include:
    • Improvements to model process representation
    • Taking advantage of CMAQ's improved log file output
    • An introduction to the Detailed Emissions Scaling, Isolation and Diagnostic (DESID) module
    • Overview of the Integrated Source Apportionment Method (ISAM)
    • Overview of the Sulfur Tracking Method (STM)
    • New documentation and modeling datasets - what is available and where to find it


  • July 27, 2017. 2:00 PM (Eastern): [Download Slides]

    Event Number: 641 164 413

    Updates in the Atmospheric Model Evaluation Tool (AMET) version 1.3

    The Atmospheric Model Evaluation Tool (AMET) (Appel et al., 2011) is a suite of software designed to facilitate the analysis and evaluation of meteorological and air quality models. AMET matches the model output for particular locations to the corresponding observed values from one or more networks of monitors. These pairings of values (model and observation) are then used to statistically and graphically analyze the model's performance.

    A new version of AMET (version 1.3) was released in July 2017. A number of updates have been made in version 1.3 from the previous version (1.2). One major update in AMETv1.3 is the replacement of the perl code with R code, which simplifies the installation of AMET as it no longer requires users to install perl and the previously required perl packages. The database setup and creation has also been simplified, with the number of required input files reduced. The MySQL credential management has been made more robust to handle password control, while the speed of the MySQL data loading has also been improved. On the AQ side of AMET, support for the AMON and FLUXNET networks has been added to AMETv1.3, along with additional analysis scripts and query options. A batch analysis script has also been added which creates pre-defined plots using a single script, eliminating the need for a user to modify and run the individual analysis scripts. A number of updates have been made to MET side of AMET, including support for MPAS data, direct read of MADIS obs files, better automatic retrieval of MADIS observations using FTP, as well as many other updates.

    This webinar will present an overview of AMET and the updates in AMETv1.3, and provide brief tutorials on the AQ and MET projects in AMET.
  • May 25, 2017. 2:00 PM (Eastern): [Download Slides]

    Event Number: 640 171 919

    An Introduction to C-TOOLS 4.0

    Presenter: Sarav Arunachalam

    C-TOOLS is a series of community tools to study local air quality due to various sources. C-TOOLS are being developed by the UNC-IE in collaboration with the U.S. EPA. Current members of C-TOOLS are C-LINE and C-PORT. Each community tool is a modeling and visualization system that accesses inputs, performs calculations, visualizes results, provides options to manipulate input variables, and performs basic data analysis - all through an easy-to-use web-based interface. The community tools based upon existing algorithms for dispersion are intended to inform the community user of local air quality due to various source types in their region of interest using a reduced-form modeling approach.

    Topics to be covered include:

    • Latest version of C-LINE and C-PORT - current members of C-TOOLS
    • Overview of new features and ongoing development
    • Preview of new members that will be added in the near future

  • April 27, 2017. 2:00 PM (Eastern): [Download Slides]

    Event Number: 648 624 623

    The Spatial Allocator 4.3, Release and Recent Updates

    Presenter: Zac Adelman

    The Spatial Allocator (SA) is a set of open-source tools that helps users manipulate and generate data files related to emissions and air quality modeling. The tools perform functions similar to Geographic Information Systems (GIS), but are provided to the modeling community free of charge. In addition, the tools are designed to support some of the unique aspects of the file formats used for Community Multiscale Air Quality (CMAQ), Sparse Matrix Operator Kernel Emissions (SMOKE), and Weather Research and Forecasting (WRF) modeling.

    The Spatial Allocator version 4.3 was release in January. This webinar will present the updates to the software. Topics to be covered include:

    • Tools for preparing satellite data of land use and atmospheric observations for use in meteorology and air quality modeling.
    • Updates to the Surrogate Tool for generating emissions spatial surrogates
    • The new BELD4SMK tool for converting BELD4 land cover data for estimating biogenic emissions with SMOKE
    • Model release process and the new Spatial Allocator GitHub page

  • March 30, 2017. 2:00 PM (Eastern): [Download Slides]

    Presenting the CMAQv5.2 Release

    Presenters: Jon Pleim, Rohit Mathur, Wyat Appel, Ben Murphy

    EPA's Office of Research and Development, Computational Exposure Division will present the recent scientific and computational updates made by EPA to the Community Multi-Scale Air Quality Model (CMAQ). Topics to be covered include:

    • Improvements to model process representation
      • Meteorology and connections to chemistry-transport calculations (land surface modeling, lightning assimilation)
      • Enabling consistent urban to hemispheric scale modeling
      • New chemical mechanisms and updates
      • Particulate matter composition and important emission sources
    • Evaluation of model updates
    • Ongoing research and development
    • Model release process and the new CMAQ website

  • February 23, 2017. 2:00 PM (Eastern): [Download Slides]

    Latest SMOKE updates and more

    Presenter: B.H. Baek, UNC Institute for the Environment

    In cooperation with the U.S. EPA, the Lake Michigan Air Directors Consortium (LADCO), and Korea National Institute of Environment and Research (NIER), and the California Air Resource Board (CARB), the UNC Institute for the Environment have been updating the Sparse Matrix Operator Kernel Emissions (SMOKE) system to enhance the quality of emissions modeling input to air quality models. Major new features in recent SMOKE include:

    • Capabilities to process gridded global emission inventories to support global and hemispheric air quality modeling
    • SMOKE4AERMOD tool development to generate AERMOD ready input files based on the U.S. EPA's National Emission Inventory (NEI)
    • Simulating real-time transponder data based emissions from Commercial Marine Vessels in the Great Lake
    • Parameterizing MOVES emissions factors lookup tables
    • Support for CARB inventory data formats and 6) various updates to support recent versions of US EPA NEI