README.md

CMAQv5.3.1 Release Notes

The Community Multiscale Air Quality (CMAQ) Model version 5.3.1 is a minor update to CMAQv5.3 that includes multiple bug fixes and a few feature additions.

Tutorial on installing and running the CMAQ test case
CMAQv5.3.1 User's Guide
Frequently asked questions for upgrading to the latest CMAQ version - NEW with v5.3.1 release!

Summary of CMAQv5.3.1 Updates

• CMAQv5.3.1 Bugfixes
• MCIPv5.1 Bugfixes
• Add support for defining chemical, region and stream families in DESID
• New grid mask files to support regional analysis with DESID and ISAM

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Summary of CMAQv5.3 Updates

The Community Multiscale Air Quality (CMAQ) Modeling System, version 5.3, is a major update. CMAQv5.3 includes several changes to the science algorithms in the base model (CCTM), as well as updates to instrumented models, pre-processors, post-processors and utilities. CMAQv5.3 was primarily developed by the U.S. EPA, and it includes contributions from research partners. The enhancements to the CMAQ modeling system since the previous release (CMAQv5.2.1) are summarized below.

Instrumented Models

• ISAM for CMAQv5.3
• Sulfur Tracking Model (STM) for CMAQv5.3
• CMAQv5.3-DDM-3D will be released later in 2019.
• Documentation for CMAQv5.2-DDM-3D

Chemistry

Photochemistry

• Removal of obsolete mechanisms in CMAQv5.3
• Revision of halogen-mediated first-order ozone loss (all mechanisms)
• Adding detailed halogen and DMS chemistry to CB6r3
• Updates to the chlorine chemistry in CB6r3 in CMAQv5.3
• Updates to the utilities that create an EBI solver
• Allow EBI solvers to conduct integrated reaction rate analysis

Photolysis Rates

• Updates to inline photolysis diagnostics and OMI data files
• Removing sporadic floating point crashes with the PGI Fortran compiler
• Updates to the inline_phot_preproc utility

New Aerosol Modules AERO7 and AERO7i

• Overview of AERO7 and AERO7i
• Monoterpene SOA
• Reorganization of anthropogenic SOA species
• Added uptake of water onto hydrophilic organic aerosol
• Corrected the conversion of inorganic to organic sulfate
• Nonvolatile POA Option in CMAQv5.3
• Streamlined SOA Module

Other Aerosol Processes

• Aerosol Dry Deposition Algorithm Updated
• Fix to Gravitational Settling Sub-Time-Step Calculation
• Simplify Propagation of Aerosol Surface Area to Heterogeneous Chemistry Algorithm

Aqueous and Heterogeneous Chemistry

• AQCHEM-KMT2: Extended inorganic and organic cloud chemistry using the Kinetic PreProcessor

Transport Processes

• Changed ACM2 PBL model vdiff to use Z-coordinates
• Changed ACM cloud model to use Z-coordinates

Air-Surface Exchange

• New NH₃ bi-directional flux in M3Dry linked to daily EPIC input
• STAGE: Surface Tiled Aerosol and Gaseous Exchange dry deposition option
• Minor updates to air-surface exchange options

Emission Updates

• DESID: Detailed Emissions Scaling, Isolation and Diagnostic Module
• BEIS Default Chemical Mapping
• Biogenic speciation update for AERO7

Process Analysis

• Process analysis for aerosol sub-processes
• IRR analysis available in EBI solvers

Structural Improvements

• Log File Output: Streamlining and Centralization
• Move Photolysis Rate Calculation to SCIPROC
• Standardized Units for Output Variables
• New Centralized Input/Output Module (CIO)
• Implementation of New Chemical Namelist Format

Diagnostic Options

• Vertical Profile Extraction: extend CCTM to output vertical profiles at specified locations

Pre-processors, Post-processors, and Utilities

• Updates in MCIPv5.0
• Updates to the ICON and BCON pre-processors.
• create_omi: Creating the OMI data file for inline photolysis
• Updates to the create_ebi utility
• Updates to the inline_phot_preproc utility
• Updates to species definition files for organic aerosols
• Updates to post-processing utilities