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CMAQ Training

October 08-October 09, 2015 Register

Now

Support

CMAS Help Desk

CMAQ v5.0.2 Release Notes

CMAQ v5.0 Operational Guidance

Document

M3User Listserv

Online Resources

CMAQ at the U.S. EPA. This is the host

site for CMAQ at the U.S. EPA

Atmospheric Sciences Modeling

Division.

NOAA CMAQ-WRF Forecast.

Real-time air quality forecasts with

CMAQ from the National Weather

Service.

CMAQ Science Document. Access the

original science alrgorithms

documentation for CMAQ.

CMAQ Peer Review. Access results of

the past two CMAQ peer review

panels.

CMAQ Bibliography. Find references to

the science in CMAQ.

Previous Documentation

submit

System Requirements

O/S Linux

Processor 64-bit x86

Memory >1 Gb RAM

Disk Space > 80 Gb

Software

VERDI, I/O API,

netCDF,MPI, IDV, Portland

Group Fortran, Intel Fortran

MCIP version 4.2

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September 16, 2015 H O M E | A B O U T | C M A S N E W S L E T T E R | C O N TA C T | S I T E M A P |

HOME

CMAQ

CMAQ is an active open-source development

project of the U.S. EPA Atmospheric Science

Modeling Division that consists of a suite of

programs for conducting air quality model

simulations. CMAQ is supported and distributed

by the CMAS Center.

CMAQ combines current knowledge in

atmospheric science and air quality modeling with

multi-processor computing techniques in an

open-source framework to deliver fast, technically

sound estimates of ozone, particulates, toxics,

and acid deposition.

Latest Version: CMAQ version

5.0.2

DOWNLOAD | DOCUMENTATION

FEATURES

Instrumented Models

Integrated Source Apportionment

Method

Direct Decoupled Method

Sulfur Tracking

Community Contributions

Volatility Basis Set (contributed by

ENVIRON International, Corp.

Two-Way Coupled MeteorologyChemistry Model

Two-way Coupled WRF3.4 and

CMAQv5.0.2

Chemistry

SOA Yield Update

Photolysis Data Update

Sulfate Inhibition Effect

Gas-Phase Chemistry

Aerosols

Aerosol Updates

Vertical Advection

Vertical Advection Time Step

Dry Deposition

M3DRY Backward Compatibility

HELP DESK

DOWNLOAD CENTER

CONFERENCES & MEETINGS

TRAINING

RESEARCH & DEVELOPMENT

COMMUNITY RESOURCES

CMAS WIKI

BENMAP

CMAQ

C-TOOLS

FEST-C

R-LINE

SMOKE

SPATIAL ALLOCATOR

VERDI

Community Modeling and Analysis (CMAS) - CMAQ https://www.cmascenter.org/cmaq/

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The meteorology-chemistry interface

processor converts MM5 and WRF output to

CMAQ and SMOKE-compatible format.

Download the MCIP version 4.2 from the

CMAS Center to take advantage of the latest

updates to the program.

Ammonia Bi-Directional Exchange

Bi-Directional Ammonia Deposition

Multipollutant Modeling

Mercury Bi-Directional Exchange

Other Updates and Bug Fixes

Meteorology Land Use

Windblown Dust

ACONC Bug Fix

PT3D Bug Fix

History of CMAQ

The Community Multi-scale Air Quality (CMAQ) modeling system has been designed to

approach air quality as a whole by including state-of-the-science capabilities for modeling

multiple air quality issues, including tropospheric ozone, fine particles, toxics, acid deposition,

and visibility degradation. In this way, the development of CMAQ involves the scientific expertise

from each of these areas and combines the capabilities to enable a community modeling

practice. CMAQ was also designed to have multi-scale capabilities so that separate models

were not needed for urban and regional scale air quality modeling.

The target grid resolutions and domain sizes for CMAQ range spatially and temporally over

several orders of magnitude. With the temporal flexibility of the model, simulations can be

performed to evaluate longer term (annual to multi-year) pollutant climatologies as well as short

term (weeks to months) transport from localized sources. With the model's ability to handle a

large range of spatial scales, CMAQ can be used for urban and regional scale model

simulations. By making CMAQ a modeling system that addresses multiple pollutants and

different spatial scales, CMAQ has a "one atmosphere" perspective that combines the efforts of

the scientific community. Improvements will be made to the CMAQ modeling system as the

scientific community further develops the state-of-the-science.

To implement multi-scale capabilities in CMAQ, several issues, such as scalable atmospheric

dynamics and generalized coordinates, that depend on the desired model resolution are

addressed. Meteorological models may assume hydrostatic conditions for large regional scales,

where the atmosphere is assumed to have a balance of vertical pressure and gravitational

forces with no net vertical acceleration on larger scales. However, on smaller scales such as

urban scales, this assumption cannot be made. A set of governing equations for compressible

non-hydrostatic atmospheres is available to better resolve atmospheric dynamics at smaller

scales. These non-hydrostatic equations are more appropriate for finer regional scale and urban

scale meteorology. Because CMAQ is designed to handle scale dependent meteorological

formulations and a large amount of flexibility, CMAQ's governing equations are expressed in a

generalized coordinate system. This approach ensures consistency between CMAQ and the

meteorological modeling system. The generalized coordinate system determines the necessary

grid and coordinate transformations, and it can accommodate various vertical coordinates and

map projections.

The CMAQ modeling system simulates various chemical and physical processes that are

thought to be important for understanding atmospheric trace gas transformations and

distributions. The CMAQ modeling system contains three types of modeling components: a

meteorological modeling system Exit EPA Disclaimer for the description of atmospheric states

and motions, emission models for man-made and natural emissions that are injected into the

atmosphere, and a chemistry-transport modeling system for simulation of the chemical

transformation and fate. The emissions model and CMAQ science codes are available from the

Community Modeling and Analysis System (CMAS) Exit EPA Disclaimer center.

The CMAQ modeling system consists of several processors and the chemical-transport model:

Meteorology-chemistry interface processor (MCIP)

Photolysis rate processor (JPROC)

Initial conditions processor (ICON)

Boundary conditions processor (BCON)

CMAQ chemical-transport model (CCTM)

The CMAQ system was designed to have a flexible community modeling structure based on

modular components. The CCTM includes the following major processes:

Horizontal advection

Vertical advection

Mass conservation adjustments for advection processes

Community Modeling and Analysis (CMAS) - CMAQ https://www.cmascenter.org/cmaq/

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Horizontal diffusion

Vertical diffusion

Emissions injection

Deposition

Gas-phase chemical reactions

Aqueous-phase reactions and cloud mixing

Aerosol dynamics, thermodynamics, and chemistry

Plume chemistry effects

Photolytic rate computation

Process analysis

The U.S. EPA Atmospheric Model Development Branch (AMDB) is developing CMAQ and

MCIP for research and regulatory use. AMDB scientists develop, test, and refine analytical,

statistical, and numerical models used to describe and assess relationships between air

pollutant source emissions and resultant air quality, deposition, and pollutant exposures to

humans and ecosystems.

CMAQ Review Process

CMAS, in collaboration with EPA scientists, has organized periodic CMAQ review panel

meetings, of 3-day duration each. The review process usually starts by inviting a number of key

scientists to participate in the process. The scientists are selected based on their expertise in

accordance with the focus of the review session. After reviewing numerous reports and articles

and completing their meeting in Research Triangle Park, North Carolina, the review panel

prepares a comprehensive report on their findings and recommendations. EPA then responds to

the comments of the reviewers. Final review reports are posted below.

Fourth Review (September 2011)

Final Report: Fourth Peer Review of the CMAQ Model, September, 2011 [PDF]

Third Review (February 2007)

Final Report: Third Peer Review of the CMAQ Model, February, 2007 [PDF]

Response to the Third Peer Review of the CMAQ Model, April, 2007 [PDF]

Second Review (May 2005)

Final Report: Second Peer Review of the CMAQ Model, July, 2005 [PDF]

Response to the Second Peer Review of the CMAQ Model, August, 2005 [PDF]

First Review (December, 2003)

Presentations (in PDF format):

AN EVALUATION OF ETA-CMAQ AIR QUALITY FORECAST MODEL (EDER)

CMAQ AEROSOL MODULE (BHAVE)

CMAQ MODELING OF ATMOSPHERIC MERCURY (BULLOCK)

CMAQ MODELING SYSTEM OVERVIEW (SCHERE)

CMAQ OVERVIEW (SCHERE)

CMAQ PLUME-IN-GRID MODELING EFFORT (GODOWITCH)

CREATING METEOROLOGY FOR CMAQ (OTTE)

DIAGNOSTIC AND IN-DEPTH MODEL EVALUATION (DENNIS)

EMISSIONS MODELING SUPPORT AND RESEARCH FOR CMAQ (PIERCE)

EVALUATION OF 2003 RELEASE OF MODELS-3 CMAQ (EDER)

FINAL REPORT

FUTURE DEVELOPMENT PLANS FOR CMAQ (SCHERE)

GAS-PHASE CHEMISTRY (GIPSON)

INVERSE MODELING TO ESTIMATE SEASONAL NH3 EMISSIONS

(GILLILAND)

LAND SURFACE MODELING AND DRY DEPOSITION (PLEIM)

LINKING ETA TO CMAQ FOR AQ FORECASTING (OTTE)

LINKING WITH NWS ETA MODEL FOR AIR QUALITY FORECASTING

(SCHERE)

MODEL EVALUATION PLANS FOR CMAQ04 (GILLILAND)

PREDICTING FATE AND TRANSPORT OF TOXIC AIR POLLUTANTS

(LUECKEN)

RECENT DEVELOPMENTS FOR PARALLEL CMAQ (YOUNG)

TRANSPORT PROCESSES IN CMAQ (PLEIM)

Final Report Summary: December 2003 Peer Review of the CMAQ Model [PDF]

Community Modeling and Analysis (CMAS) - CMAQ https://www.cmascenter.org/cmaq/

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Community Modeling and Analysis System (CMAS)

General inquiries about the CMAS Center and questions about the web site should be directed to cmas@unc.edu

For technical questions about software and data, please refer to our Help Desk

Page Last Modified: 10/24/2014 12:19:20 PM

Community Modeling and Analysis (CMAS) - CMAQ https://www.cmascenter.org/cmaq/

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